sebacic acid/dicarboxylic acids

Sebacic Acid/Dicarboxylic Acids

CIR EXPERT PANEL MEETING DECEMBER 13-14, 2010

ADMINISTRATIVE

Memorandum

To: CIR Expert Panel Members and Liaisons From: Monice M. Fiume MMF Scientific Analyst/Writer Bart A. Heldreth, Ph.D., Chemist BAH Date: November 18, 2010 Subject: Final Report (Draft) on the Dicarboxylic Acids At the August meeting, the Expert Panel, in a 7-1 vote, issued a Tentative Report with the conclusion that the 12 dicarboxylic acids and salts and 44 esters of dicarboxylic acid that are included in this report are safe for use in cosmetic products in the present practices of use and concentration. Were ingredients in these groups not in current use to be used in the future, the expectation is that they would be used in product categories and at concentrations comparable to other in these groups. At the August meeting, the concern raised was regarding the branched ingredients and their lack of dermal penetration data. No additional data have been received regarding this concern, which is addressed in the Discussion of the report. Since August, additional details were added to some existing studies. Also, the section on peroxisome proliferation was shortened, as requested by the Panel. At this meeting, the Panel should be prepared to issue a final report.

CIR Panel Book Page 1

REPORT HISTORY: DICARBOXYLIC ACID AND THEIR SALTS AND ESTERS

July 10, 2009

: SLR was issued

Initial review of the draft report. The recommendation was made to add 5 additional dicarboxylic acids – oxalic, malonic, succinic, glutaric, and adipic – and their salts and esters

September 2009 Panel meeting

The report was tabled for reorganization into (1) acids and salts and (2) esters. It was also agreed that oxalic acid should be removed. It was also felt that more data should be available.

December 2009 Panel meeting

The report has been completely reorganized. A new search was done and the text was updated with much new data. August 2010 Panel meeting

At the meeting, the Panel concluded (with a 7-1 vote) that these ingredients are safe for use in cosmetic products in the present practices of use and concentration. A concern was expressed regarding the extent of dermal absorption for certain long-chain, branched diesters (which have molecular weights greater than 500 g/mol and log Kow

values of 10 or greater). In this view, were it demonstrated that dermal penetration was low for the entire group, no further data would be needed. If not, then a concern was expressed about the absence of toxicity data for several branched-chain alcohols that would be produced if dermal penetration and subsequent metabolism could occur.

Since August, additional details were added to some existing studies. Also, the section on peroxisome proliferation was shortened, as requested by the Panel.

Final Report - December 2010 Panel Meeting


Updated Search – 09-21-10 – last 12 mos entries only Sebacic 09-21-10 10 hits/0 useful 111-20-6 OR 184706-97-6 OR 109-43-3 OR 110-40-7 OR 122-62-3 OR 359073-59-9 OR 10340-41-7 OR 7491-02-3 OR 69275-01-0 OR 17265-14-4 OR 478273-24-4 OR (DICAPRYL AND CAPRYL AND SEBACATE) OR (DIISOSTEARYL AND SEBACATE) Malonic-Succinic-Glutaric 09-21-10 74 hits/0 useful 141-82-2 OR 105-53-3 OR 110-15-6 OR 2922-54-5 OR 150-90-3 OR 106-65-0 OR 123-25-1 OR 2915-57-3 OR 2530-33-8 OR 14491-66-8 OR 93280-98-9 OR 925-06-4 OR 110-94-1 OR 1119-40-0 OR 71195-64-7 OR (DIISOSTEARYL AND GLUTARATE) Adipic 09-21-10 23 hits/0 useful 124-04-9 OR 627-93-0 OR 141-28-6 OR 103-23-1 OR 106-19-4 OR 105-99-7 OR 105-97-5 OR 26720-21-8 OR 155613-91-5 OR 110-33-8 OR 141-04-8 OR 57533-90-1 OR 58262-41-2 OR 59686-69-0 OR 27178-16-1 OR 33703-08-1 OR 108-63-4 OR 6938-94-9 OR 62479-36-1 OR 155613-91-5 OR 85117-94-8 OR 16958-92-2 OR (ALKYL AND ADIPATE) OR (DIHEXYLDECYL AND ADIPATE) Azelaic-Dodecanedioic 09-21-10 10 hits/3 possibly useful 123-99-9 OR 9619-43-3 OR 52457-54-2 OR 17265-13-3 OR 27825-99-6 OR 132499-85-5 OR 693-23-2 OR 131252-83-0 OR 129423-55-8 October 26, 2010 – identified a SIDS document on PEG-3 Methyl Ether (now included in text)


Dicarboxylic Acid Data Profile* – December 2010 – Writers, Monice Fiume and Bart Heldreth

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Acids and salts: malonic acid X X X succinic acid X X X X X X X X X X sodium succinate X X X X X disodium succinate X X X glutaric acid X X X X X X X X adipic acid X X X X X X X X X X X X azelaic acid X X X X X X X dipotassium azelate disodium azelate sebacic acid X X X disodium sebacate X X X X dodecanedioic acid X X X X X X X Esters diethyl malonate X X X X X X X X X decyl succinate dimethyl succinate X X X diethyl succinate X X dicapryl succinate X dicetearyl succinate diisobutyl succinate diethylhexyl succinate X dimethyl glutarate X X X diisobutyl glutarate diisostearyl glutarate dimethyl adipate X X X diethyl adipate X dipropyl adipate X dibutyl adipate X X X X X X X X X X X dihexyl adipate X dicapryl adipate X di-C12-15 alkyl adipate ditridecyl adipate X X X X X X dicetyl adipate diisopropyl adipate X X X X X X diisobutyl adipate X X X X diethylhexyl adipate X X X X X X X X X X X X X diisooctyl adipate X diisononyl adipate X X X X X diisodecyl adipate X X X dihexyldecyl adipate diheptylundecyl adipate X dioctyldodecyl adipate X X X diisocetyl adipate X X diisostearyl adipate X X isostearyl sebacate diethyl sebacate X X X X dibutyl sebacate X X X dicaprylyl/capryl sebacate diisopropyl sebacate X X X X X diethylhexyl sebacate X X X X X X X X X X X X dibutyloctyl sebacate diisooctyl sebacate X dihexyldecyl sebacate dioctyldodecyl sebacate X diisostearyl sebacate X dioctyldodecyl dodecanedioate X X X X X diisocetyl dodecanedioate X X X X X *“X” indicates that data were available in a category for the ingredient; it is not an indication of positive or negative findings Alternate shading indicates a related set of ingredients


TRANSCRIPTS/MINUTES

DR. SNYDER: Most of those other

anthraquinones also cause liver damage, right?

DR. COHEN: Yes, yeah.

DR. BELSITO: Julie, any comments?

MS. SKARE: No.

DR. BELSITO: Okay. Good. So now we're

turning to our original schedule, dicarboxylic

acids, which is Pink 3, also known as sebacic

acid. We tabled this last December to reorganize

the reports into acids and esters. And we agreed

to delete oxalic acid and so the report has been

rewritten. And there's a feature on diester

metabolism. And we can ask Dan to comment on

that. Although we tabled it, we sort of did this

hint-hint to industry at that time that there were

additional data that we'd want to see, including

impurities data for a representative long and

short chain dicarboxylic acid. And for a short

and long chain diester. And dermal penetration,

there could be octenyl water partition

coefficients and information on irritation and

sensitization and use concentration.

Belsito Team - Aug 2010

And we've got a pretty good data dump on

those and the question is whether we need

additional data, particularly in terms of the

carcinogenicity issue that relates to the

diethylhexyl sebacate with a tumor promotion on

page 46 to 47 in the document. I just had a

question to ask Dan and Curt and Paul how they

felt about that, and then Dan about his metabolism

portion of those that they put in.

DR. LIEBLER: Well, the metabolism, that

was an addition. There was -- that was a new

thing or expanded. I don't have any notes here

that there was anything that I flagged about the

metabolism. I mean, it wasn't remarkable or

surprising or anything like that. And it's mostly

about adipic acid and its esters.

MS. FIUME: A lot of this information

was probably new because I did a complete new

search and we added a bunch of new documents. So

it may not have been that there was concern about

it, just it wasn't in the report and happens to be

there now.

DR. BRESLAWEC: The last time the panel

saw this report you made it pretty clear that

there was an adequate report and review. So

although we took the subject matter --

DR. BELSITO: It was hugely changed. I

asked for my old book and it did not help me.

MS. FIUME: Yes. Well, that's --

DR. BELSITO: Great job, incidentally.

DR. LIEBLER: I mean, the description of

metabolism is extensive and helpful. It's not

surprising. It's not surprising to me.

DR. BELSITO: Okay. So this, my

question to Curt and Paul was the diethylhexyl

adipate increasing the (unintelligible) cellular

adenomas and carcinomas in male and female rats --

or mice?

SPEAKER: Mice. Correct.

DR. BELSITO: Whether this concerns you?

Another 2-ethylhexyl groups have been looked at

and had the same issue.

DR. SNYDER: Liver tumors are already

problematic in the mice because they're so

prevalent, so common. Seeing the increased

incidents was difficult to determine. There were

other studies here. There was no increase, both

dermal. None in dogs, a year and --

DR. KLAASSEN: It's not a mutagenic.

DR. LIEBLER: So just focusing on the

diethylhexyl esters?

DR. BELSITO: Yeah. I mean -- yeah.

DR. LIEBLER: So I had a couple comments

on this section. So we're on approximately page

27 of the report, page 75 of the Panel Book. And

it begins with the term "mechanism" and about a

page or so long summary of peroxisomes

proliferation mechanism and so on. And after

reading through it a couple times I felt it was

perhaps a bit lengthy given that we're going to

end up saying that this is really not particularly

relevant to human risk assessment. And so I just

wrote I think this lengthy section should be

significantly shortened down to perhaps about two

paragraphs. Paraphrase the mechanism. The reason

it is even being considered, which is the


ethylhexyl component of these esters being related

to a notable peroxisome proliferator DEHP. And

then note that the effect is toxicologically well

studied, but not relevant to humans. So, I mean,

you can get across the key information, but

paraphrase the mechanism down about two

paragraphs.

And then of course there is a fair

amount of study that had been done in mice with

the diethylhexyl -- a debate that goes on for

three -- two pages. And that also perhaps could

be shortened and paraphrased a little bit. So

that was my suggestion on that material.

MS. FIUME: Doctor, can I ask, from

those studies which very important points would

you need to see brought out boldly versus

paraphrasing the rest of it? Just the effect that

it's peroxisome proliferator and reference the

studies?

DR. BELSITO: Proliferator

(unintelligible). And that is the mechanism of

action in mice, but it's not relevant to humans.

MS. FIUME: Okay.

DR. LIEBLER: I don't know if you guys

read the Rodricks at all, the triclosan review

that we talked about earlier from Clinical Reviews

and Toxicology. They did a lengthy version of

this, but they essentially introduced the top of

the peroxisome proliferators by pointing out some

of the characteristic features of peroxisome

proliferators -- the kinds of enzyme activities or

proteins and so forth that are induced or genes

that are induced. What are the typical things one

observes when that's going on? And then they

proceeded to talk about it in the case of

triclosan. You could use that paragraph about

mechanism to set yourself up in the same way by

sort of saying here's peroxisome proliferator.

It's been well studied, reference, reference,

reference. And here's -- here are some of the

characteristic things one observes with chemicals

that act by this mechanism. And then you can

highlight those things in the studies of the

adipate -- diethylhexyl adipate esters in a mouse

because you're essentially pointing this out, you

know, five-fold induction of peroxyl beta

oxidation. That's a classic hallmark sign. You

know, there were certain enzyme activities that

would way up and, you know, palmitoyl-CoA oxidase

is way up.

So, anyway, that might be the approach

that you could take and that would help you get

through that material in probably about a page.

Maybe a little more than a page.

MS. FIUME: Okay.

DR. KLAASSEN: And the classic

information is really about a drug called

clofibrate. And it also does this in laboratory

animals and causes tumors. But humans have been

taking it for decades and it doesn't. So this is

just another peroxisome proliferator probably

doing it via the same mechanism and has little or

no role as to these.

DR. BELSITO: Okay.

DR. KLAASSEN: The study is of

peroxisomal (unintelligible) gene knocked out by

understood phenomena. We don't think it has

relevance.

DR. BELSITO: And then that obviously

should go in the discussion.

DR. KLAASSEN: Right.

DR. BELSITO: On page 4, Monice, of the

report under Ultraviolet Absorption, it says that

it wasn't detected in that range. That's for a

specific product, cetyl-b, which I believe is

dibutyl adipate.

MS. FIUME: Okay. We were discussing

that. We are going to find that paper.

DR. BELSITO: Yeah. I looked it up.

It's cetyl-b was the trade name and it translates

to dibutyl adipate. So it's for a specific

product.

Then on page 9, this is under Animal

Dissolution, Metabolism, and Excretion. The first

paragraph really should be moved to Percutaneous

Absorption. There are some, I mean, at least some

of it should be under that section as well since


it's a dermal study.

On page 11, towards the bottom third of

the page, disodium azelate. What are melanomata?

MS. FIUME: I'm sorry?

DR. BELSITO: What are melanomatas? Do

you mean melanomas?

MS. FIUME: I'm pretty sure that was the

wording in the paper.

DR. BRESLAWEC: Yeah. I actually looked

it up because I wondered if maybe it was a

specific type of (unintelligible).

DR. BELSITO: Okay. It's an eye

melanoma, ocular melanoma. Never heard that term.

No. Live and learn.

On page 16, under Malonic Acid, the pH

of the sperm suspensions was 4.0.

MS. FIUME: I will double check that.

I'm sorry about that. That would be my guess, but

I will check it.

DR. BELSITO: On page 18, the

genotoxicity. You didn't tell us until the end

that it was summarized in Table 7. If you could

tell us up front so instead of giving a lot of

reading, if the reader isn't interested they can

just go to Table 7.

MS. FIUME: I'm doing that for all of my

tables.

DR. BELSITO: Okay.

MS. FIUME: If they're summarizing, we

had discussed in the past the front and back. So

I remember the front for all of your tables.

DR. BELSITO: Okay. And then for

succinic acid, the second line from the bottom of

that paragraph, it's sodium succinate less than or

equal to 10 micrograms.

MS. FIUME: I believe it's --

DR. LIEBLER: Milligrams? It just

doesn't say.

DR. BELSITO: I looked it up in the

table and it was micrograms.

MS. FIUME: It is micrograms.

DR. BRESLAWEC: Micrograms.

DR. BELSITO: I think everything else

was just little typos and things.

MS. FIUME: Just so you're aware for the

next time you see it, I do have some additional

details for some of the studies on succinic acid

and glutaric acid. So where I do have details

were not available, it doesn't change the outcome

of what was there, but there are more details

(unintelligible) animals and things like that.

DR. BELSITO: Okay.

MS. FIUME: So they will be added in.

DR. BELSITO: On page 49, the

dioctyldodecyl and the diisoctyl, the

concentrations aren't given. I'm assuming they

didn't appear in the paper, but just making sure.

DR. LIEBLER: So on these, just to be

clear, you said that you were adding some other

information from references on doses and animals

and things like that? Because I had a couple of

things I flagged where there was so little

information it was really hard to interpret the

studies.

MS. FIUME: The examples would be, say

on page 16 of the text versus succinic and

butyric, I did have doses.

DR. LIEBLER: Okay. I have one at the

top of page 13 under adipic acid.

MS. FIUME: Okay. That I will double

check because I don't think I actually have that

one, but I will double check that.

DR. LIEBLER: Okay. And then there's

another one on page -- sorry, Don, to jump in on

you.

DR. BELSITO: No, (unintelligible).

DR. LIEBLER: On page -- I guess it's on

CIR Book -- oh, it's on page 13. Excuse me. Same

thing at the bottom: Adipic, glutaric, succinic.

Okay. That's the one you were talking about,

right? That you had fixed. Okay.

MS. FIUME: Under the subchronic oral,

is that where you're --

DR. LIEBLER: Yes.

MS. FIUME: Yes. For the glutaric I

have the NOAEL. It was 15 males and females.

I'll have additional dose information.

DR. LIEBLER: Okay.


MS. FIUME: So we'll add some details in

there.

DR. LIEBLER: Good.

DR. BELSITO: And just another comment,

you know, where we point out that certain of the

ingredients we're reviewing are not listed for use

by the European Union, is there a way of finding

out why? Is it simply that no one has --

MS. FIUME: Actually --

DR. BELSITO: -- filed for that or --

MS. FIUME: -- they're all there now. I

don't know why the first time I searched they did

not show up. But now all of them are listed in

the EU inventory.

DR. BELSITO: Okay. So that just needs

to be changed?

MS. FIUME: Mm-hmm. And also on that

same paragraph, instead of saying that they're

listed for use by the EU. without restriction, it

will be changed to they are in the EU inventory.

DR. BELSITO: Okay. So other than for

that I had no real substantive comments. A lot of

some grammar, spelling issues, spacing issues, but

otherwise I was fine going out with safe as used.

And just the biggest point of the discussion is

the mechanism of carcinogenicity in rodents not

being relevant to humans.

Paul, Curt, Dan?

DR. LIEBLER: I'm fine with that. I

have a couple of other things I wanted to ask you

about over here. One is on top of page 23 at the

report, page 71, Panel Book page. There's a

reference to SC administration and it also looks

like there's a topically applied administration in

that same paragraph. Is that one study or

multiple studies for cutaneous and SC? I think

those are different routes.

MS. FIUME: Is it --

DR. LIEBLER: Top of page --

SPEAKER: Twenty-three?

DR. LIEBLER: Twenty-three.

DR. BELSITO: Percutaneous.

DR. LIEBLER: Percutaneous penetration

of radio labeled diethyl malonate was studied,

blah, blah, blah. And then a little later in that

paragraph absorption estimated (unintelligible)

peak recovery after SC administration. It looks

like the same reference.

DR. BELSITO: It's a different study.

DR. LIEBLER: Those are two different

studies?

DR. BELSITO: Yeah.

DR. LIEBLER: Okay. My bad then. And

then at the top of page 25 or actually the bottom

of page 24, top of page 25, there's a

parenthetical. DMSO is an active penetrating

carrier of substances through tissue, fat soluble

substance such as diethylhexyl adipate more

realistically studied dissolved in corn oil. It

may be true. Just as an editorial comment that's

inserted into the middle of the description of the

study. I'm not sure if that really belongs there.

MS. FIUME: Okay. Would you like it --

DR. BELSITO: Deleted?

MS. FIUME: -- to be anywhere? Because

there were -- I remember in reviewing the study

they were trying to make the point that if the

DMSO was the vehicle it may not have given an

accurate picture, whereas corn oil might. Do you

feel that --

DR. LIEBLER: If the authors stated that

then you should simply say that the authors

pointed out that. It looks like you guys just

sort of said oh, that doesn't make sense. Here's

how I would do it.

MS. FIUME: Okay.

DR. LIEBLER: And added it in there.

And then the figure -- so some of the figures on

the properties -- log Kow versus chain length and

so forth are useful, but the Chart 3 just is out

of control.

DR. BELSITO: Table 3 or Figure 3?

DR. LIEBLER: Chart 3. I guess it's

figure -- well, it's labeled as Chart 3 and it's

on page -- Panel Book page 138. You know, you

could probably render the same information with

just a scatter plot with one kind of symbol. You

can summarize the information and you don't really


have to know what each point is, so.

DR. HELDRETH: It was originally grouped

in color so it was clear here's what the

diisopropyls look like.

DR. LIEBLER: Yeah.

DR. HELDRETH: I agree.

DR. LIEBLER: Okay. Because the other

plots give you kind of that information, similar

information. I like those, but this one is just

out of control. So that's it.

DR. BELSITO: Okay. Paul? Curt?

MS. FIUME: Can I ask a question? If I

need to address this in discussion, for the

diethylhexyl adipate again, reproductive

androgenic effects, the effects on body weights,

it's not -- to me at least it didn't look as

completely negative to the reader. It may be

negative, but there were scattered effects. Do I

need anything to discuss for the discussion on

that or was it okay as is?

DR. SNYDER: My notes say lots of repro

data, no negatives. So that's what my

interpretation was.

MS. FIUME: Okay.

DR. SNYDER: But then again, there's

lots of repro data.

MS. FIUME: Because I think -- if I

remember it was mostly effects on body weight and

gestation length.

DR. BELSITO: I had no comments about

the repro data. It didn't disturb me at all.

MS. FIUME: Okay. So like on the bottom

of page I have the researchers stated that the

effects observed in the fertility study in

conjunction with the ovarian effects described

earlier in the repeated dose study suggests that

diethylhexyl adipate disturbed ovulation. So I

don't need to address any of that information in

the discussion?

DR. SNYDER: Well, I think it is

relevant that they're all attributed to the over

effects. Yeah. That's fine. It'll capture

that. Right.

MS. FIUME: Okay.

DR. BELSITO: Anything else? Okay.

Safe as used. A little discussion. Big

discussion on the proxo proliferation, a little

discussion on the repro.

Okay. Moving along to stearyl

heptanoate. This is the other final that we have

this go-round. So this is Blue 2. And at the

June meeting we issued a tentative report. Safe

as used. PCPC gave some technical comments which

have been addressed. There was an EU monograph on

stearyl olivate that became available and it's

approved in the EU without use restrictions. This

information has been added. So if anything, more

information that just further supports our safe as

used conclusion.

And in this report I don't think that I

really had anything substantive to add. So, Curt,

Paul, Dan, are you happy with it?

DR. LIEBLER: Happy with it.

DR. SNYDER: Happy.

MS. FIUME: Dr. Belsito, again, for the

EU information, rather than saying without

DR. BERGFELD: Will you comment on the

hazelnut?

DR. ANDERSEN: Yes, the hazelnut we will

have to be saying that we are amending the

hazelnut conclusion, absolutely.

DR. MARKS: Okay, thank you, Wilma.

Next we're in the dicarboxylic acids group, Pink

Book 3. So, we saw the last draft report in

December of 2009. This was tabled for

reorganization. The first section of this report

deals with the salts, the second with the esters,

and we're at the point now of potentially issuing

a tentative final report.

Comments? First of all, are these

ingredients safe? Is there insufficient data?

Unsafe? Team members?

DR. SHANK: They are safe.

DR. MARKS: Safe.

DR. SLAGA: Safe. However, this was a

very overwhelming review.

DR. MARKS: I think for me the biggest

issue when I looked at the sensitization data, if

Marks Team - August 2010


you look at diethyl sebacate, that on page 50 of

this document -- let me see what page point --

that was Panel Book page 98, there are a number of

case reports of a medication in Europe that had

this as an ingredient and caused severe

dermatitis. So, when I went back to look at what

kind of data we had to determine a safe limit and

the concentrations in this were significant in

these case reports in that medication. If you

look at -- right before that on CIR Panel Book 96,

that there's an HRIPT with a body cream containing

1.5 percent and did not have any sensitization

potential. So, I would say, safe with the

exception of limit diethyl sebacate to 1.5 percent

unless we have a compelling reason not to limit

that one particular dicarboxy acid. Otherwise I

felt it was safe.

DR. SHANK: What is its use level?

DR. HILL: So, we have some missing

alcohols again.

DR. MARKS: I think, I -- let me see,

where did I have use? I thought it was above.

DR. EISENMANN: It's on page -- Panel

Book 150, it's 1.5. I think that's the page where

we are.

MS. FIUME: Yes, that's correct.

DR. EISENMANN: It's 151 actually.

DR. SHANK: Page 151.

DR. EISENMANN: Right.

DR. SHANK: It's use level is 1.5

percent, that's what was tested.

DR. MARKS: Correct. That's where they

probably got that use level. But then I guess my

concern, when I look down here on the

concentrations of use, it was only on that six

dermal contact, whatever that is, and nothing for

-- well, that's the only use, isn't it? So, I

guess it would be fine to say use. Okay?

DR. SHANK: Yes.

DR. MARKS: Thank you, Ron. I'll

withdraw that limit. Makes it simpler. But I

might include that in the discussion because I

think it should be an alert, that if they're going

to use more than 1.5 percent they should be

concerned that this may be a significant

sensitizer.

Any other comments? Ron, you were

asking about alcohols again. Forget it?

DR. HILL: Yeah, never mind for the

moment.

DR. MARKS: Okay. Page 151. Okay. So

tomorrow I'm going to move that we issue a

tentative final report with the conclusion that

these cosmetic ingredients are safe as used.

Any other comments?

DR. SHANK: Are the appendices going to

be part of the published report? Some appendices

added at the end?

DR. MARKS: That's page 116? Are you in

the Panel Book?

DR. SHANK: Yes.

DR. MARKS: That's Appendix 1, yes, and

great summaries. The question is, do you want to

take this page to do those? Like the irritation

sensitization is collected in a nice table in an

-- under appendices.

DR. SHANK: And then there's another

appendices on the esterase metabolites. So, are

these going to be included in the published

report? It's just a question.

MS. FIUME: Alan, we're broaching new

ground, so I don't know the answer to that.

DR. SHANK: Okay.

DR. ANDERSEN: Nor do I. I think I

would turn it back. Does that look like stuff

that a reader of this report should look at as

part of the safety assessment? If so, hell yes.

DR. BERGFELD: I liked it.

DR. ANDERSEN: The panel chair gets two

--

DR. MARKS: I liked the tables,

actually, that summarize it in a glance, but we'll

-- this is the tentative final report. Once it's

sent out, we'll see how you decide on the

appendices and we'll hear what the other team --

Ron, do you have a preference? I think Ron Shank

and I prefer a boiled down table. Tom? And --

DR. HILL: So, you're talking about a


table that would list -- basically itemize the

studies and give references similar to what we saw

in --

DR. MARKS: Right.

DR. HILL: Yeah, that would be okay.

And -- I'm kind of good either way. I just

flagged -- I said there were some missing

alcohols. I don't see octadecyl, I don't see

isononyl, I don't see hexyldecyl, and I don't see

heptadecyl or isocetyl. So, there are one, two,

three, four, five alcohols that do not appear

anywhere in these appendices, but are in the

esters.

DR. HELDRETH: They were searched, but

there was no data.

DR. HILL: There was no data. For me

that's a big flag and a big issue.

DR. SLAGA: For what reason?

DR. HILL: Because we should be able to

generate those in skin and are they doing anything

there to the lipids in skin.

So, we have this whole slew of growth

factor receptors, particularly tyrosine receptor

kinases that are responsive to unusual effects of

lipids and we know nothing about these apparently,

and they're all larger, more lipophilic, but not

excessively so, unusually structured. We don't

know what happens to them alcohols.

That was really the only -- I think this

was the same thing I flagged back in December when

we originally looked at this and I was hoping that

I would see something to make me feel a little bit

more comfortable about this.

DR. BERGFELD: It would sound to me that

you would want that to occur in the discussion

that there was no information on those alcohols.

DR. HILL: Yes, and for me it kind of

affects how I feel about the conclusion for this

report, but I have to think about that some more.

DR. MARKS: Ron, let me know what you

think between now and tomorrow morning.

DR. HILL: I will.

DR. MARKS: Since I'm the one presenting

this, making the move either it's safe or -- would

you feel more comfortable of certain (inaudible)?

So, we can further discuss that.

Any other comments? Tom? Ron Shank?

DR. HILL: Because -- in terms of

there's this interesting thing, I was debating

whether to bring it up, but I'm going to bring it

up, in terms of effects on cell growth we have an

interesting thing. It appears that a number of

these larger dicarboxylic acids actually have

anti-proliferative type effects. But there's a

possibility that some of these more lipophilic

alcohols could have the opposite effect. So then

when you study an ester you get opposing effects

and there's some complexities there that I'm not

even sure I know how to begin to deal with, but

it's something to put out there for thought.

DR. SLAGA: The reorganization of this,

great job. I -- even though it's overwhelming it

still -- it would have been impossible unless it

was organized this way.

DR. HILL: I agree.

DR. MARKS: I guess --

DR. ANDERSEN: And I think, Jim, at a

minimum tomorrow you need to flag that there's an

ongoing concern about the absence of data on

certain of the alcohol metabolites, because that's

a truism. Search it, you don't find anything.

Then you're going to have to go on to figure out

what you want to do about that, but I think Ron

has made the point when we did the nonanoic acids,

it's a presentation that we've heard, it focuses

on clearly some missing data, and at some point it

may or may not become critical. But I guess

there's a subtext here that industry might want to

be paying attention to because at some point the

absence of data on some of these branch-chained

alcohols may turn out to be a sticking point.

I don't know what the threshold is for

generating some data, but they certainly have been

flagged that there's some gaps.

DR. MARKS: Then I think the issue is do

we move to more as, again, to issue a tentative

final report that these ingredients are safe? Or

how do you want to handle that? Again, if you


want to let me know, Ron, before tomorrow morning,

because if we have concern about lack of data of

these alcohol metabolites, should that not come up

before we moved that these ingredients are safe?

I mean, one could say we have concern, but not

significant concern, we'll handle it in the

discussion, or we've got to be right up front and

say, okay, how much does this concern affect this

decision and what ingredients in this decision?

Tom and Ron Shank? Do you want to weigh

in? You're willing to continue with safe?

DR. SHANK: I am, yes.

DR. MARKS: Okay. What I may do

tomorrow is, say, move that we issue a tentative

final report as safe, but then, Ron Hill, I asked

you to comment about the concern about the alcohol

metabolites.

DR. HILL: Right now that would seem to

be okay with me.

DR. MARKS: Good. One other thing for

discussion, Alan, and I can ask industry, sebacic

acid on Panel Book page 49. That said it was

originally isolated from beef tallow. I presume

sources of this from India and China are not using

beef tallow presently and, if so, do we need a

prions boilerplate?

MR. BAILEY: I think that the raw

material that's produced in the U.S. is not a

problem assuming it complies with FDA's current

requirements. In sourcing raw materially

globally, then perhaps that one might be a

different issue. And so, I mean, I think if

that's something you're concerned about then we

can certainly go in somewhere in the discussion or

elsewhere that would be appropriate.

DR. MARKS: I guess I would feel more

comfortable, since we're not certain that

worldwide sourcing and now more things being

imported in, that it's easy enough to put the

prions boilerplate in there, the alert. Alan,

what do you think about that? To me that was a

red flag when I saw beef tallow.

DR. ANDERSEN: Well, it's in the report.

This is going to the International Journal of

Toxicology at some point, so noting our

expectation that FDA's rules regarding process of

materials of beef origin should be followed is

simply good advice.

DR. MARKS: Okay.

MR. BAILEY: I can't remember thinking

back to the FDA guidance whether that extends

beyond materials that are isolated directly from

cattle or to secondary materials, derivatives,

which is what this would be. Perhaps we can look

at it overnight and provide some clarification

tomorrow, but it seemed to me it did not go that

far, but I can't, off the top of my head, recall.

And in that case, since this is a

secondary material, then it would not be necessary

to put that kind of caution in there.

DR. MARKS: Okay.

DR. ANDERSEN: The other point is that

if this is issued as a tentative conclusion, there

is still time to resolve that issue, so we do the

best we can at this point. But if, for example,

whatever is meant by distillation, stands any

chance of tracking a prion along with sebacic

acid, then we don't want that used nor would

anybody want that used for cosmetic products. So,

we have a direction to take this one way or the

other that I think leads to the right point. I

think some more homework is appropriate.

DR. MARKS: Okay. Next is stearyl

heptanoate. In 1994, we, the expert panel, issued

a safe as used. The review was reopened and then

at the June meeting this year, the panel issued a

tentative amended report, safe, and so, let me

see, who moves -- I'll be moving tomorrow that we

issue a final report, safe.

Are there any comments? Safe? Hearing

no concerns about that, editorial comments?

DR. SHANK: I had only one.

DR. ANDERSEN: Microphone.

DR. SHANK: We have a reference number 8

monograph on stearyl olivate, but it doesn't seem

to appear in the text. It's a reference without

-- but it's not -- I couldn't find it in the text

and I wondered why.


second to your first motion. There -- now has a

second motion to table and there's no -- oh, is

there a second to table?

DR. MARKS: Second.

DR. BERGFELD: All right. There's not

discussion on the table, so all those in favor of

tabling with the intent of making an amended

conclusion please indicate by raising your hands.

Unanimous.

Thank you. Very robust discussion.

Thank you very much.

The next ingredient is Dr. Marks, the

dicarboxylic acids.

DR. MARKS: So, in December of 2009,

this group of cosmetic ingredients under the

dicarboxylic acids were tabled so that the report

could be reorganized. And now we have the acids,

the salts, and the esters. They've been separated

in this report. It's a large number -- if you

look on the introduction on CIR panel book page

48, you see the number of ingredients. And with

that in mind we move to issue a tentative final

Full Panel - Aug 2010

report with safe as the conclusion for all these

ingredients.

DR. BERGFELD: Is there a second?

DR. BELSITO: Second.

DR. BERGFELD: Second. Any discussion

-- further discussion?

Dr. Belsito?

DR. BELSITO: Yeah. Yes, in the

original report, on page 5 it had stated that

disodium -- or dipotassium acetate, disodium

sebacate, and C12-15 alkyl adepate are -- let's

see, I'm getting this backwards, right? Some of

them were not approved for use in the EU, but

we're now told all of them are.

MS. FIUME: They're all listed.

DR. BELSITO: Okay. So that needs to be

changed on page 5 and on the -- in the page 51 in

the summary.

And also, it was Dan's feeling that the

section on page 27 on the mechanism of

hepatocellular carcinoma, the peroxisome

proliferation could be significantly shortened.

And he made those editorial comments to Monice

yesterday.

DR. BERGFELD: Dr. Hill?

DR. HILL: Yeah. The safe conclusion

was not unanimous with this group, and I guess

I'll offer up a dissenting opinion on that based

on the same concerns that I raised in the December

meeting. But we kicked the can down the road by

tabling on the unknowns related to -- there were

five alcohols on which we have no toxicology data

whatsoever in the literature. If we had some sort

of dermal penetration dependence data that

indicated -- once we get past a certain log-P and

a certain molecular weight in all the vehicles

that are used in marketed products -- that we

wouldn't have any dermal penetration, I wouldn't

be concerned.

But the only dermal penetration data we

have on anything with a relatively larger log-P --

and it's not that large -- is a Bibber '96 study

on diethylhexyl sebacate. And so my specific

concern is, is there penetration of some of these

molecules into the skin? They are used in

occlusive applications like deodorant. If we had

data that indicated they just sit there on the

skin in the stratum corneum and anything that's

there is there for days, gets sloughed off with

skin cells or is removed in washings, I would be a

lot more comfortable. But we have long-chain

alcohols that are attached here. If there's

biotransformation by lipases to monoesters

liberating alcohols -- we have long-chain alcohols

and nothing is known about the toxicology of

those. I don't see why they wouldn't be in cell

membranes in the skin, and if they get in cell

membranes in the skin then there are possible

biological effects such as modulation of tyrosine

receptor kinases that could occur with such

lipophilic compounds and we know nothing about

that.

So, you're asking me to support a

conclusion of safe on no science, and I can't do

it.

DR. BERGFELD: Dan, can you -- Dr.


Liebler, also comment?

DR. LIEBLER: Ron, I don't know why I'm

always the guy who has to respond to you, but I

guess --

DR. HILL: Because you have relevant

expertise in this area.

DR. LIEBLER: I know, I suppose so. I

guess I just don't share your concern. I think

that the penetration of long-chain alcohols was

likely to be very low. And the --

DR. HILL: Let me just say that we're

not talking about the penetration of the alcohols.

We'd be talking about the diesters, because that's

the way they're delivered. We're not -- so --

DR. LIEBLER: So then, even lower --

DR. HILL: It could be even lower, I

agree --

DR. LIEBLER: Right. So --

DR. HILL: But we have no information to

that effect is the problem.

DR. LIEBLER: So, yeah. I think the

difference here is the -- how -- what your comfort

level is with inference based on the available

data. I'm comfortable with inferring from the

available data, and I think you're not. And we've

had this discussion several times.

So I don't think there's unknown,

unprecedented metabolism of these things waiting

to be discovered. The metabolism and fates of the

diesters and their alcohol cleavage products --

and the acids, for that matter -- are reasonably

well established.

So. I don't share your concern. I

think the idea of, for example, modulation of

tyrosine kinase biochemistry and so forth is, I

would say, speculative.

DR. HILL: It is speculative, but it's

not that speculative. I mean -- and we do know at

least there was a couple of these, I had the page

marked, where we do have -- ditridecyl adipate

gets into skin approximately 11 percent in rats.

Now, that's rats, not humans. We'd say the data

is lower. If it gets into the skin, I think it's

reasonable to assume we're going to be generating

those alcohols. And I guess the nature of my

concern is is that we know nothing about those

alcohols. There's zero data on these five

particular alcohols in the literature. Zero data.

So, we're basing everything on some assurance that

there's no absorption, and I don't think we have

that assurance. I think, you know, the

probability that very much would be absorbed is

pretty low, but we don't have data to support

that.

And I mean, the times in my life when

I've used anything other than petrolatum, it

doesn't just sit there, after a while it's gone.

It goes somewhere. If it's just all there in the

stratum corneum, then later I'm sloughing off skin

cells and washing it off and it's gone. But I

just -- there's no science in my mind that

supports for me to say I conclude it safe, period.

DR. BERGFELD: Could I offer a

possibility that this be discussed in the

discussion portion of the document?

DR. HILL: Yeah. I think, you know, if

it's put there in the discussion it captures --

and I've put on the record my concerns. It

captures it. I'm outvoted and we go forward, you

know.

DR. BERGFELD: Any other comments by any

of the panel members? Dr. Marks, none?

Seeing none, I'll call for the vote.

All those in favor of approval of safe? All

right. Abstaining or opposed? Okay.

DR. HILL: Opposed.

DR. BERGFELD: One opposed, no

abstaining. Thank you.

With the understanding that in the

discussion the penetration will be discussed.

Thank you.

Then going on to the next ingredient

which is in a green book, isoparaffins. Dr.

Belsito.

DR. BELSITO: Yes. This is the first

time we're looking at this report, and in June a

literature review of the ingredients was issued.

And the list of ingredients -- I'm not going to


CIR Meeting day 2 Page: 40

Anderson Court Reporting -- 703-519-7180 -- www.andersonreporting.net

1 isononanoates and all that -- those parts. And,

2 hopefully, we can have our -- you know, at the

3 next meeting, have a good discussion on whether

4 these are long shots or not, in other words, if

5 they're lipophilic, probably really concerned and

6 so forth, because I'd hate to pull --

7 unnecessarily pull ingredients off the list when

8 there's a good reason to believe that it's not a

9 problem.

10 DR. BERGFELD: Well, thank you for that

11 clarification of who does what.

12 All right. Well, then we move on.

13 We're moving on to the second ingredient under the

14 reports advancing and that's sebacates by Dr.

15 Marks.

16 DR. MARKS: So, this is the second time

17 we've looked at the sebacates. In the September

18 2009 meeting we decided to table these ingredients

19 so that we could expand the number and I have a

20 feeling we're going to have a discussion again

21 procedurally how to go. Our team felt that we

22 should continue to table these ingredients with

ANDERSON COURT REPORTING 706 Duke Street, Suite 100

PANEL - DEC 2009 CIR Meeting day 2 Page: 41


1 the aim of splitting the acids and salts into one

2 group -- they are used as pH adjusters -- and then

3 the esters into another group, rather than having

4 them all mixed in as is in the present document.

5 That could either be, as we discussed,

6 whether this should be two separate documents or

7 one document and just have the document organized

8 so these ingredients were split, and we felt that

9 we could proceed with one document. And then we

10 also felt that within this list, that we should

11 reopen three of the esters that have already been

12 determined to be safe by the CIR panel, and that's

13 the diethylhexyl adipate, the dibutyl adipate, and

14 the diisopropyl adipate. So, we felt some more

15 work needed to be done on the document and,

16 therefore, recommend to table it.

17 DR. BERGFELD: Is there a second to

18 table?

19 SPEAKER: Second.

20 DR. BERGFELD: Second. There's no

21 discussion on the table. Motion, all those in

22 favor of tabling, please indicate by raising your




1 hand?

2 DR. BELSITO: Any discussion?

3 DR. BERGFELD: No discussion on the

4 table. It's four against four? So, the chair has

5 to vote. I'll vote to table. So, this particular

6 ingredient has been tabled and let's go over why

7 it's being tabled again.

8 DR. MARKS: Well, the first is that we

9 felt the document could be reorganized and that

10 really by uses, so the acids and the salts are

11 used as pH adjusters and then the esters had other

12 uses. And so the document would be split to

13 discuss those two groups together, and that we, as

14 part of this document, reopened three esters which

15 had previously been determined by the CIR as all

16 are safe to be included in this new amended.

17 DR. BERGFELD: May I ask, Alan, is this

18 really editorial or is this truly -- does it truly

19 have a need for being tabled?

20 DR. ANDERSON: Yes, I would have said

21 that was an editorial change. It's just a matter

22 of reorganizing the document, whether it is split




1 into two or split into two pieces in one document.

2 We have lots of experience with both approaches.

3 It's simply a question of approach. It doesn't

4 address the question of any real additional data

5 needs. So, I'm not sure there's a benefit to

6 tabling from that standpoint.

7 DR. BERGFELD: How about the addition of

8 the other previously approved ingredients?

9 DR. ANDERSON: I think --

10 DR. BERGFELD: Does that fit with the

11 first comment?

12 DR. ANDERSON: There is -- there are

13 data that are available in the other safety

14 assessments that previously the panel has

15 completed. To the extent that you want those data

16 incorporated, tabling it to do that step is, I

17 think, a valid thing to do because clearly they're

18 not in there now.

19 DR. BERGFELD: Don? Comment?

20 DR. BELSITO: Well, I mean, we obviously

21 didn't vote to table, but some comments. First,

22 yes, I mean, I think the other three should be





1 included. Jim, I think you said dibutyl, you mean

2 dioctyl.

3 DR. MARKS: Okay. Thank you, Don.

4 DR. BELSITO: The biggest discussion we

5 had revolving around this was oxalic acid, which

6 did not -- I mean, all of the safety data on that

7 specific acid, particularly in terms of causing

8 renal calculi, was not in this document. And we

9 actually thought since we didn't see it listed as

10 having any cosmetic uses, that unless there were

11 cosmetic uses for oxalic acid or its esters that

12 it be dropped from this family because of those

13 issues with renal toxicity.

14 DR. BERGFELD: So, your recommendation

15 under the conditions that we were tabling this is

16 to reconsider the inclusion of oxalic acid?

17 DR. BELSITO: Well, to first of all

18 confirm whether, in fact, it's used -- currently

19 being used, and, if not, then our recommendation

20 would be to remove it from this family because of

21 those issues that were being countered and because

22 of the huge amount of data that we'd have to




1 review and grapple with.

2 DR. LIEBLER: If I could just elaborate

3 on that.

4 DR. BERGFELD: Don?

5 DR. LIEBLER: Yeah, I think the idea of

6 including the smaller diacids and their esters and

7 salts was mainly to expand the chemical space to

8 things that are possibly relevant. But in getting

9 down to oxalic acid, you run into some unique

10 toxicology that's very well documented, very

11 prominent, and quite problematic, and we don't

12 even know if this is used as a cosmetic

13 ingredient. So, rather than get tangled up in all

14 of that, it's worth considering deleting the

15 oxalic acid from this report.

16 DR. BERGFELD: John Bailey?

17 MR. BAILEY: Yeah, I think we didn't

18 have time in getting these additional ingredients

19 to survey -- do our usual survey of use and use

20 levels, so we can't answer definitively whether

21 that's the situation or not, so I think we need

22 some more information. I would point out that in




1 Europe, oxalic acid is on annex 3 for hair dyes,

2 so presumably, you know, that may be a use. And

3 we haven't done the research necessary to get more

4 information about how it got there and use levels

5 and so forth. So, I would say, certainly oxalic

6 acid is in the textbooks. We all know about it,

7 but there may be some additional information that

8 would be relevant that we simply, you know, didn't

9 have time to get.

10 DR. BERGFELD: So, that's a promise to

11 get?

12 MR. BAILEY: Certainly, yeah. We'll do

13 our usual survey of --

14 DR. BERGFELD: Okay. Any further

15 discussion? Don?

16 DR. BELSITO: Yeah, I guess, just to

17 follow up on Dan's point, there is such a

18 voluminous amount of literature on oxalic acid

19 that even if it's used in cosmetics, do we want to

20 get bogged down dealing with why that is going to

21 be safe in a cosmetic product and reviewing all of

22 that literature on oxalic acid? Or would it be




1 better simply to keep all the ingredients, which

2 is a large number of ingredients we have right

3 now, get rid of oxalic acid and, in fact, if it's

4 used, we can always look at oxalic acid

5 specifically rather than as a member of this

6 group? Because I just think we're going to get

7 hugely bogged down even if it's used in trying to

8 explain why it'd say brief discontinuous use on

9 the hair, no absorption, yadda, yadda, yadda. But

10 we're going to have to look at all the data

11 anyway.

12 MR. BAILEY: Yeah, I concur.

13 DR. BERGFELD: So, we might entertain a

14 motion at this time to delete oxalic acid from the

15 list.

16 DR. BELSITO: I would like to make that

17 motion.

18 DR. BERGFELD: Is there a second?

19 Second. Is there a discussion of that

20 recommendation?

21 Curt?

22 DR. KLAASSEN: No problem.





1 DR. BERGFELD: Paul? Dan? Ron?

2 That's okay.

3 DR. HILL: I have no problem with that.

4 DR. BERGFELD: Okay, we'll call for the

5 vote to delete oxalic acid from the list of

6 ingredients. All those in favor? Unanimous, with

7 the intent of taking it up as a separate

8 ingredient at some time in the future when it's

9 been declared how it's used and how frequent it's

10 used.

11 MR. BAILEY: To that end, we'll include

12 that in our survey just so we'll have that

13 information.

14 DR. BERGFELD: Thank you. Ron?

15 DR. HILL: Yeah, in our discussions

16 yesterday our starting point was really a

17 suggestion that Ron Shank made to separate into

18 two documents, and then we talked about two sort

19 of separate sections of the main document because

20 in the consideration of the diacids, they're

21 pretty much -- their uses are as pH adjusters and

22 then similar like that. There are a lot of esters




1 here. You'd have to pull out that list, Ron, that

2 you had where we would seem to be depending on

3 read-across data for things like genotoxicity,

4 tumor-promoting potential, and even sensitization.

5 Am I mistaken there? We have direct data on the

6 sebacates, some of the adipates, and a number of

7 the others we don't. Isn't that correct?

8 DR. SHANK: That's correct.

9 DR. HILL: So, we're looking at a pretty

10 high number of read-across, which was another

11 reason, I think, basis, for why we had suggested

12 the tabling idea, so that we had the time to

13 really better assess those gaps.

14 DR. BERGFELD: We need to record your

15 response, Ron.

16 DR. SHANK: I agree with Dr. Hill that

17 we have some information on the esters, but the

18 esters are used quite differently from the acids

19 and salts. And that's why I had suggested that we

20 split them, either two reports or within the same

21 report, make it very clear that the acids and

22 their salts are -- can be handled one way and the




1 esters will have to be handled a different way.

2 DR. ANDERSON: Yeah, I really don't

3 think that that's a problem in terms of overall

4 strategy. It provides the opportunity to be a lot

5 clearer to the reader, that we understand the

6 fundamental difference between how these chemicals

7 are used in cosmetics. So I think we'll simply do

8 that.

9 Now, I am concerned about the suggestion

10 that read-across may be problematic. I would ask

11 the panel to reserve that, to focus on the data,

12 where the data gaps are, and what your comfort

13 level is going to be with the ability to use data

14 on one chain length ester of dicarboxylic acid to

15 inform your decision about another chain length,

16 all other things being equal. So, having all data

17 on all ingredients is not the norm. So, I think

18 there needs to be a comfort level with some degree

19 of read-across as you evaluate these data. Only

20 you folks on the panel can reach that level of

21 comfort, but I would ask you not to veto it a

22 priori.




1 DR. HILL: Well, I'm relatively new,

2 but, you know, I mean, I still have the same

3 issues. There's some of the alcohols that we just

4 talked about in the pelargonate section that show

5 up again here. And if there's no reason to

6 believe that there's any significant generation of

7 those alcohols in the skin, if there's no reason

8 to believe that those alcohols would lead to

9 sensitization in the skin, then there's probably

10 -- and there's no reason to believe that either

11 the alcohols or, in fact, these esters that we

12 have no data on could promote tumor development in

13 skin, then we don't have a problem. But I'd like

14 to know, when I make a final vote, that I'm

15 comfortable whether that is valid scientifically,

16 and that's really the only concern I have is that

17 it's scientifically valid to make that conclusion.

18 DR. ANDERSON: Point well taken.

19 DR. BERGFELD: Thank you. So we're

20 going to be tabling the sebacates and we've had

21 the discussion and we're going to reorganize the

22 document, and we're going to get some more





1 information on some of the ingredients. Is that

2 correct?

3 DR. ANDERSON: Mm-hmm.

4 DR. BERGFELD: All right.

5 DR. ANDERSON: And we're deleting oxalic

6 acid --

7 DR. BERGFELD: And we're deleting oxalic

8 acid, thank you.

9 DR. ANDERSON: Deleting oxalic acid.

10 Nobody has specifically said it, but let me say

11 it, we're also going to delete the oxalic acid

12 esters.

13 DR. BERGFELD: Correct. All right.

14 It's time to move on to the next ingredient, the

15 PEGs. Dr. Belsito.

16 DR. BELSITO: Yes. At our September

17 meeting, we reviewed results from industry

18 essentially done on tape- stripped skin as a

19 method of looking at PEG toxicity on damaged skin

20 because previously we had a conclusion that

21 restricted the use of PEGs on damaged skin. We

22 had a chance to look at what would be absorbed.



Cosmetic Ingredient Review Panel December 8, 2009 Page: 143


1 Sebacate? Sebacate?

2 SPEAKER: You asked that last time.

3 DR. BELSITO: Sebacates. Sebaceous.

4 Okay, so we're going to go to the --

5 SPEAKER: Sebacates.

6 DR. BELSITO: Dicarboxylic Acid Salts

7 and Ester Report. That, I know how to pronounce.

8 Okay. And I guess as part of the

9 add-ins now, we've been provided with a final

10 report that we did on dioctyl and diisopropyl

11 adipate. And we're back in December. We tabled

12 this to look at a whole bunch of related

13 dicarboxylic acids that we agreed to incorporate

14 into this report. And we've gone out and got

15 information on azelaic acid as used in topical

16 drugs. And we've got some new unpublished data

17 that we saw briefly at the September meeting but

18 didn't really have time to digest. And so now

19 we've got this tentative safety assessment and all

20 of the information in it is in here, short of a

21 discussion and a conclusion, so.

22 Then we've heard a little bit from Bob




1 this morning on dermal penetration. We don't have

2 a lot of genotox and carcinogenicity here. But we

3 do for the azelaic acid, which is used as a

4 topical, have some information. So if there is a

5 concern about that, I guess we still have Bob here

6 and he can tell us what he would think about the

7 absorption of these.

8 So with that as an intro, the question

9 is do we have enough here for this group of

10 dicarboxylic acids, which now will contain azelaic

11 acid, malonic, succinic, glutaric, adipic, and

12 sebacic acid and their salts and esters that are

13 listed in the Cosmetic Dictionary to go with a

14 safe as used conclusion?

15 SPEAKER: We have, to date, not received

16 use data.

17 MS. ROBINSON: It's forthcoming. Carol

18 (inaudible) by the next --

19 SPEAKER: Mic, please.

20 MS. ROBINSON: The use information is

21 forthcoming. Carol has said that it may be here

22 by the next meeting.




1 DR. BELSITO: But how can we --

2 SPEAKER: By the next meeting? April?

3 DR. ANDERSON: We don't have it.

4 DR. LIEBLER: Can I get a clarification

5 of that? Were these the data that were from the

6 American Chemistry Council?

7 MR. ANSELL: That data has been

8 included. This is the use concentration on all

9 the add-ons, which came to us in too short a time

10 to turnaround between these.

11 DR. LIEBLER: Okay, so we did -- last

12 time we did talk about the American Chemistry

13 Council data that we thought would be useful. And

14 there was a question of whether or not we joined

15 -- or CIR joined in or somehow got access to that.

16 So I see some of the data in this report. And

17 just, I'm curious, how do we get that?

18 MS. ROBINSON: Well, to date, we haven't

19 received any additional data from the last

20 meeting, from the reports. So what you see in the

21 report is essentially the same that we saw at the

22 last meeting.




1 DR. BELSITO: Okay. And one comment I

2 have is are the impurities sufficient? We have

3 impurities only for dimethyl malonate and

4 diethylmalonate and diethylhexyl adipate. We

5 don't have impurities for the other compounds

6 we're reviewing.

7 So I just, you know, sort of throw that

8 out as an aside, to get the sense of chemists

9 looking at the way these are manufactured as to

10 whether they would be concerned about that.

11 DR. LIEBLER: I'd like to see data that

12 describes the impurities, at least the types of

13 compounds that would be present as impurities and

14 their approximate ranges of concentrations.

15 DR. BELSITO: And then in terms of

16 concentrations of use, I mean, we do have some

17 information here if we go to Table 4, particularly

18 for the sebacic acid groups we have. We have some

19 for the succinate. We have some for adipic acid

20 and its groups, and then we have azelaic acid. So

21 we have some concentrations of use. And we have

22 that standard, you know, asterisk boilerplate that





1 if where we're not giving a concentration of use,

2 we assume it's being used in the same

3 concentration as the other groups.

4 So I'm not sure -- I mean, it would be

5 nice to get updated information, and there are

6 lots and lots of blanks here, I agree. But I

7 think the issue that bothered me the most was the

8 lack of impurities in all these groups that we're

9 adding in.

10 And then, of course, we're relying on

11 azelaic acid and the data from the Finacea and the

12 Azelex cream to support a lot of our systemic or

13 lack thereof of systemic toxicity. So again, I

14 just throw out is there any concern here about

15 absorption of the other molecules? Because for --

16 and again, it's back to Dan whether you can. You

17 know, is the systemic toxicity going to be

18 generalizable across all these dicarboxylic acids

19 or are there any that you would be concerned

20 about?

21 DR. LIEBLER: Aside from parameters that

22 would affect absorption and distribution, I'm not




1 aware of any sort of pharmacodynamic reasons why

2 different chain length dicarboxylates would have

3 different toxicological effects.

4 DR. BELSITO: Curt?

5 DR. KLAASSEN: I agree.

6 DR. SNYDER: And the overall toxicity is

7 relatively low. Pretty high OB50s.

8 SPEAKER: Okay.

9 DR. BRONAUGH: I guess there was an

10 absorption study in guinea pig skin of the diethyl

11 -- what is it? -- the diethylhexyl sebacate, which

12 the molecular weight looks to be under 500. You

13 know, sometimes, if you have a large family of

14 ingredients, it might be useful if we could know

15 what the molecular weight is, what the logP is, so

16 you could look through and have a better sense.

17 But, you know, this data is in a

18 hairless guinea pig -- or the guinea pig, anyway,

19 that was given to us, where they said it was

20 readily absorbed. But I would imagine some of

21 these molecules are absorbed. But, you know, it's

22 really kind of hard to say without, you know, how




1 to compare them without knowing a little bit more

2 about their chemistry.

3 DR. KLAASSEN: One would think that

4 these would be extremely water soluble and not be

5 absorbed so well, right?

6 SPEAKER: (inaudible) the mic.

7 DR. KLAASSEN: Yeah.

8 SPEAKER: Sometimes I -- if it --

9 DR. KLAASSEN: You know, in regard to

10 these dicarboxylic acids, I guess it'd be my

11 impression that they'd be so water soluble that

12 they probably wouldn't be absorbed. I think it

13 would be nice to see some partition coefficients,

14 etcetera.

15 DR. BRONAUGH: It would take a little

16 extra time, but maybe it'd be worthwhile if -- I

17 mean, this data could be calculated in a family

18 like this and we'd have a better idea.

19 DR. KLAASSEN: And in your talk this

20 morning didn't you say that there was some EPA or

21 FDA website that had a lot of that data on there.

22 DR. BRONAUGH: It has the software where




1 you can calculate logP and water solubility just

2 knowing the SMILES code of any ingredient. And

3 again, the SMILES codes are available on the NIH

4 site, for many compounds.

5 So it might be useful to have that

6 sometimes.

7 DR. KLAASSEN: Yeah, I agree 100

8 percent.

9 DR. BELSITO: But if the toxicity is the

10 same, at least systemic toxicity is, that was the

11 reason I asked the question. And we have use that

12 looks like it's not going to above 10 percent in

13 cosmetics. And then we have Azelex cream, which

14 has been looked at by FDA, that's 20 percent for

15 treatment of acne. Then I think I'm okay as long

16 as I don't see cosmetic products coming out above

17 10 percent or certainly over the 20 percent in

18 terms of, you know, okay, you know, is there

19 absorption, you know, and what are slight

20 differences in absorption.

21 But I agree in principle with what Bob

22 is saying. As we create these superfamilies, it





1 would be nice if CIR would go to that website and

2 provide us with a list of molecular weights and

3 logPs. You know, particularly when it comes to

4 picking, you know, if there is an issue about

5 absorption, what ingredient do we want as the

6 model ingredient to assure the safety for the

7 entire family. Well, it would be the one that we

8 would predict from these various parameters would

9 be most likely to be absorbed. So I think it

10 would be helpful.

11 MR. ANSELL: To the discussion on

12 systemic safety, we would like to point out that

13 CIR has already conducted and found safe as used

14 three of the adipates, including diethylhexyl,

15 dibutyl, and diisopropyl. And that the

16 diethylhexyl has already gone through a complete

17 NTP screen through carcinogenicity.

18 DR. ANDERSON: I think the, excuse me,

19 Table 2 already includes many of the data you're

20 talking about. Admittedly they are buried in

21 amongst all of the other chemical and physical

22 properties. But the American Chemistry Council




1 report, in fact, did use the EPA program to

2 calculate logPs, and these are included. So for

3 dimethyl sebacate, it's 3.4 for a logP; for

4 diethylhexyl sebacate, it's 3.74 there. Just

5 outside, if you will, of the -1 to 3 range that

6 would suggest penetration, but not far enough

7 outside so that I'd be comfortable for giving them

8 a free ride. I think you'd have to presume there

9 is some absorption of these things. Then the

10 question becomes what's the toxicity, which is

11 rather low. And I wouldn't kiss them off on the

12 basis of dermal penetration.

13 SPEAKER: Yeah.

14 DR. ANDERSON: But I take your point

15 that a table that presents just molecular weight

16 and logP, if those data are available, paints an

17 interesting picture that you'd like to see.

18 DR. BRONAUGH: Yeah, I forgot about that

19 data. I don't have a copy. Linda has our copy of

20 the book. I forgot that that was done for this

21 series of compounds. And I think it was very

22 useful. There were some gaps in there that maybe




1 could have been filled in, but I think that's

2 useful.

3 SPEAKER: That's good to know.

4 DR. LIEBLER: You could represent the

5 calculated logP values in a plot, like the plot

6 for the phenyls that Bob showed during his talk,

7 in which you'd number, instead of just using round

8 dots as the points, you actually use numbers as

9 the points. And the numbers could refer back to

10 the compounds in a table. And what that would

11 allow us to do is see much better which compounds

12 are within the range or close to the range that's

13 typically associated with the potential for

14 absorption.

15 DR. ANDERSON: That raises an

16 interesting idea of what would that plot look like

17 since we have calculated logP values on one axis

18 as a function of molecular weight on another.

19 DR. KLAASSEN: Well, those are two of

20 the more important characteristics of chemicals

21 that are important to us. And, you know, a lot of

22 these that we have, you know, like boiling point,




1 vapor pressure, density even, we have all of these

2 other things. It's kind of like the important

3 data gets lost in the minutiae.

4 SPEAKER: Yep, the --

5 DR. LIEBLER: With the Henry's Law

6 constant, you're saying.

7 DR. ANDERSON: I take your point. Just,

8 we need a good chemist on staff.

9 DR. BELSITO: Now, were the data from --

10 all of the data from this dioctyl and diisopropyl

11 adipate report incorporated into this report?

12 Because it seems like they have not been.

13 And did I understand, Jay, from your

14 comment, that there is another adipate that we've

15 also previously reviewed out there?

16 MR. ANSELL: Yeah, we have three

17 adipates that were CIR reviewed, which have not

18 been included. These were diethylhexyl, dibutyl,

19 and diisopropyl adipate.

20 DR. BELSITO: Okay. So then there's the

21 diethylhexyl has also not been incorporated into

22 this at this point?





1 MS. ROBINSON: If it was from the

2 original report, it has not been incorporated.

3 But an updated search was performed, so anything

4 outside of that is in the report.

5 DR. BELSITO: Okay. So we have one

6 other report, other than this one, that needs to

7 be incorporated into this document, as well?

8 SPEAKER: (inaudible)

9 DR. BELSITO: Okay.

10 MR. ANSELL: We also -- the NTP study,

11 we don't believe has been incorporated on a whole

12 series of materials. I'm also unclear as to

13 whether the -- we did obtain from ACC robust

14 summaries that we were requested to -- and the

15 cover letter suggests they were included, but

16 Valerie's suggesting they're not. So I think

17 there's some data that needs to be included.

18 MS. ROBINSON: The robust summaries from

19 ACC were incorporated, but we haven't received any

20 additional information that we asked for prior.

21 MR. ANSELL: The data which was

22 requested of us in September, though, I think was




1 Dan's question. And we did find robust summaries,

2 and I do believe they have been incorporated.

3 DR. LIEBLER: I couldn't tell what was

4 different. I guess I didn't have the previous

5 book, so. I saw some references to the American

6 Chemistry Council HPV summaries. Is that what

7 you're referring to, Jay?

8 MR. ANSELL: Yeah.

9 MS. ROBINSON: Yes, those are new.

10 DR. LIEBLER: Those are new.

11 MS. ROBINSON: Yes.

12 DR. LIEBLER: Since September.

13 DR. ANDERSON: That's correct. Those

14 were not in the document.

15 DR. LIEBLER: Okay.

16 DR. ANDERSON: And the only issue from

17 the panel's perspective is that now that you

18 understand dicarboxylic acids were in the American

19 Chemistry Council report, there is a couple of

20 points of overlap with this safety assessment, and

21 is that enough?

22 DR. BELSITO: Okay. Where do we get the




1 information as to what was in the American

2 Chemical report? How do we divine that from this

3 document?

4 DR. ANDERSON: Well, if you go to page

5 34, for example, for the question, really, of the

6 genotoxicity data, then there's specific mention,

7 you know: Mammalian cell gene mutation assay.

8 Two ingredients in this assessment were included

9 in the ACC report and were negative in the mouse

10 lymphoma assay.

11 DR. BELSITO: Okay, so you're talking

12 about the mutagenicity studies, in particular.

13 DR. ANDERSON: Yes.


15 DR. ANDERSON: Yeah, that was the --

16 DR. BELSITO: Wasn't clear where you

17 were.

18 DR. ANDERSON: Yeah, I'm sorry. That

19 was the major gap. Without those data, the

20 genotoxicity section was really quite bleak.

21 DR. BELSITO: Okay. So where are we

22 with this? Are we going insufficient for




1 impurities? Are we going insufficient for more

2 concentration of use? Are we going safe as used

3 when we add in the NTP summaries and the

4 information from the dioctyl, diisopropyl,

5 diethylhexyl adipate documents that were

6 previously published?

7 Paul, where are you?

8 DR. SNYDER: Sounding an awful lot like

9 insufficient. I mean, Dan's comment to the

10 impurities issue, he's not comfortable with the

11 absence of additional impurities data.

12 DR. LIEBLER: So I'd be happy with

13 representative data for some of these compounds

14 for impurities. I mean, we have a wide range of

15 things from small dicarboxylates to big,

16 long-chain esters, which are going to result from

17 different processes and are going to have

18 different impurities. We may not have impurity

19 data for every compound in the table, but I'd like

20 to see representative impurity data from compounds

21 that represent the processes that go into these

22 products.





1 And I was struck, in concentrations and

2 frequency of use, that it seemed like they were

3 inversely related. The compounds with recorded

4 significant frequencies of use had almost no

5 concentration data and the compounds with bigger

6 numbers for frequency of use tended to have no

7 concentration data.

8 Talking about Table 4.

9 DR. ANDERSON: Yeah, and that's very

10 likely an artifact of the late addition of many of

11 the compounds.

12 DR. LIEBLER: Do you think the

13 information's available and we just haven't gotten

14 it into a table yet?

15 DR. ANDERSON: I think that's the case.

16 DR. BELSITO: That's what we're told,

17 that Carol --

18 DR. LIEBLER: I see, okay.

19 DR. BELSITO: So then what we're looking

20 at is Dan would like some representative impurity

21 data. Would you like to mention any specific ones

22 you'd like or just leave it open-ended back to the




1 council and industry for some representative

2 impurity data?

3 DR. LIEBLER: I'd like to see impurity

4 data on the dicarboxylates.

5 DR. BELSITO: But which ones? Any

6 specific one that you're concerned about, or?

7 DR. LIEBLER: How about sebacate.


9 DR. LIEBLER: As representative. And

10 then how about succinate as -- or malonate as

11 representative? So you get a longer one and a

12 shorter one.


14 DR. LIEBLER: And then how about the

15 impurity data on short esters of both of those and

16 long esters of both of those? I think that

17 represents the chemical space reasonably well.

18 DR. BELSITO: Okay. So then what we're

19 suggesting is that we are going insufficient for

20 impurities. And we would like to see something on

21 the sebacates or sebacic acid, and either malonic

22 or succinic acid, and then whatever two you




1 choose, some impurity data on short- and a

2 long-chain ester of each of those acids. And we

3 would appreciate getting updated concentration of

4 use, particularly for those ingredients that have

5 considerable use. And assuming that that data

6 looks clear, I am guessing that we would be going

7 safe as used for these dicarboxylic acids.

8 DR. BERGFELD: So are you going out

9 insufficient or are you tabling it?

10 DR. BELSITO: No, insufficient. I mean,

11 it's only -- it's at a pink stage.

12 MR. ANSELL: But there's so much data

13 which was not included in the report, and so many

14 added after, it would be possible for us to have

15 provided the data. We would prefer it be tabled

16 to include CIR's reports, to include the NTP

17 study, to include the actual concentrations of

18 use.

19 DR. BELSITO: But I guess, Jay, I don't

20 see how tabling it versus us telling you what we

21 find is insufficient in the current report really

22 changes things since it's at a pink stage. I




1 mean, it's not like it's going out for a final.

2 And if we were going out for a final, it was going

3 to be, you know, we're saying it's insufficient,

4 and you're going to get the data for us before the

5 next meeting. But, I mean, if anything, I mean,

6 PC has been --

7 DR. BERGFELD: Are you asking for an

8 announcement?

9 DR. BELSITO: -- after us to expedite

10 the process. Well, this expedites the process.

11 It moves it up to the next stage and it tells you

12 where we're at.

13 DR. BERGFELD: Are you going out for

14 insufficient data announcement or --

15 DR. BELSITO: Yeah.

16 DR. BERGFELD: -- insufficient final

17 announcement?

18 DR. BELSITO: No, this is not even a

19 final. This is pink, Wilma.

20 DR. BERGFELD: No, no, I know, but I'm

21 --

22 DR. BELSITO: We haven't even gotten --





1 DR. BERGFELD: I know, but we had jumped

2 over the announcement part in our new progression.

3 But you're going to input in this one

4 announcement, insufficient data announcement.

5 DR. BELSITO: Right.

6 DR. BERGFELD: It's different than a

7 final.

8 DR. BELSITO: It's not a final, it's

9 just a --

10 DR. BERGFELD: No, no, I know that. But

11 we had done away with announcements. We've done a

12 few of them, but we've done away with that process

13 a little bit. Haven't we? Alan? We were trying

14 to expediate the flow.

15 DR. ANDERSON: Yeah. I think in terms

16 of process, at the last meeting the panel agreed

17 to move forward to prepare a draft report which in

18 our judgment, given your comments, would be ready

19 to be issued as a tentative report. There were a

20 couple of oopses in that process in that a couple

21 of background reports prepared by the panel didn't

22 get captured. The other oops is that the panel




1 flagged these very long list of additions too late

2 for the council to in any way be expected to

3 respond with use concentration data. So those are

4 -- there's some serious gaps in those data.

5 But it is at a stage when you would be

6 expected to do one of two things: Issue an

7 insufficient data announcement or issue a

8 tentative report. And you flag that there are

9 clearly data that you want. In our expedited

10 process of keep it moving, this is ready for an

11 insufficient data announcement. That's,

12 processwise, that's where it is.

13 There is the issue of the couple of

14 oopses. And I wouldn't be upset if you used that

15 as a basis for saying, look, we got to fix these

16 gaps. We've got the reports from previous safety

17 assessments that weren't captured. You need to do

18 that. And arguably that would allow enough time

19 for the use data to come in. And I don't see any

20 difficulty in tabling it. I would write in the

21 post-meeting announcement that part of tabling it

22 is the expectation for the impurities data that




1 Dan has outlined.

2 The risk of that is that we get to April

3 and those data don't show up.

4 DR. BELSITO: Exactly.

5 DR. ANDERSON: And that's --

6 DR. BERGFELD: However, the document is

7 cleaned up and all of the --

8 DR. ANDERSON: Yeah, but you just

9 delayed it --

10 DR. BELSITO: But cleaning up the

11 document is not -- I mean, if all of the

12 information we needed was in the oops documents

13 that didn't get in and an update in the

14 concentration of use, then I would be very happy

15 tabling it. But I'm just concerned that if we

16 want the impurities data and, you know, Dan is the

17 man I go to to tell me if we need that, and we

18 just table it, even if Alan says, oh, by the way,

19 you know, I don't think, based upon past

20 performance of industry, we're going to get it.

21 And then we're going to be sitting at the April

22 meeting where we were at the December meeting.




1 So, I mean, it's -- we go insufficient, we list

2 what we need, clean up the document, update

3 concentration of use, give us some impurities,

4 then I think it's very clear what we're looking at

5 for safety. And that's what I would -- I mean,

6 that's my argument. In the spirit of trying to

7 expedite getting these documents done, I think the

8 best way to expedite it is to be very upfront as

9 to where we are.

10 SPEAKER: Well said.

11 DR. KLAASSEN: There's one additional

12 comment I'd like to make. And that is one major

13 group of chemicals in this larger class is oxalic

14 acid and its various compounds. And the toxicity

15 of oxalic acid is well known, if it gets absorbed,

16 in that it's quite -- produces kidney injury.

17 And, in fact, that's the toxicity from ethylene

18 glycol, is that it's metabolized oxalic acid and

19 it causes severe kidney injury. And while I don't

20 think we're probably getting enough absorbed here

21 to be a problem, there's really not much data in

22 this entire document on oxalic acid. And I just





1 want to make sure people are aware of that.

2 DR. BELSITO: There's a lot of

3 literature on it.

4 DR. KLAASSEN: There's a lot of

5 literature, but it's not in here.

6 DR. BELSITO: Yeah, I know.

7 DR. KLAASSEN: And I think somehow we

8 need to at least address oxalic acid in a

9 discussion or something, if there is good reasons

10 why we haven't kind of paid special attention to

11 it. And, in fact, it's -- yes, there's a lot of

12 information out there. In fact, it's -- also, a

13 lot of plants contain oxalic acid and -- so,

14 anyhow, it needs to be somehow addressed.

15 DR. LIEBLER: I didn't see oxalic acid

16 listed in Table 4, or any of its derivatives

17 listed in Table 4. Is it used in cosmetic

18 products? Oxalic acid or oxalate esters?

19 MR. HAVERY: We don't have any reported

20 uses for oxalic acid.

21 DR. LIEBLER: So I think that -- my

22 recollection is that last time we met, in




1 September, this category was expanded at Ron

2 Shank's suggestion based on incorporating the

3 greater range of chemistries. But I think the

4 rationale was going across the chemical space as

5 opposed to the cosmetic ingredient space, and we

6 might have picked up some unnecessary compounds in

7 doing so; oxalic acid and its esters being

8 representative of that.

9 DR. BELSITO: But they're in the

10 dictionary. And we thought we could cover them in

11 this report. One of the things that we get

12 criticized for by groups such as the Environmental

13 Working Group is that there are X-number of

14 thousands of chemicals in the dictionary and we

15 have looked at only a certain small percentage of

16 them. And so that was the whole purpose for

17 grouping these. And so if oxalic acid is in the

18 dictionary and the functions are similar to the

19 other dicarboxylic acids, and we feel that the

20 safety can adequately be reviewed, you know, we do

21 it. And then there's that footnote at the end

22 saying, well, you know, oxalic acid and its esters




1 aren't being used, but if they were to be used,

2 we're assuming that they would have the same

3 function and the same concentration as everything

4 else in this report.

5 SPEAKER: (inaudible) review.

6 DR. LIEBLER: They may just -- and

7 oxalic acid may be somewhat unrepresentative of

8 this class of compounds. I mean, in the case of

9 oxalic acid in the kidney, it forms these very

10 insoluble crystals with calcium, calcium oxalate,

11 very insoluble. So it's kind of the --

12 mechanistically, it's an outlier.

13 DR. KLAASSEN: And it is at the end of

14 the chain that we're talking about. I mean, it is

15 the smallest one.

16 DR. BELSITO: Well, if mechanistically

17 it's an outlier, and if that's the issue, and then

18 if you're concerned about absorption, then we

19 could easily delete it by saying that it is an

20 outlier. You know, that we cannot group this

21 specific dicarboxylic acid with the others. On

22 the other hand, if you're not concerned about the




1 level of absorption from a cosmetic product, I

2 mean, if it's a true no-brainer, then we should

3 add it. If it's not a true no- brainer, then we

4 shouldn't. And I guess that's a point that, I

5 mean, if you want to raise tomorrow, we can

6 certainly do that.

7 DR. LIEBLER: Yeah, I just don't know

8 what the data are on absorption of oxalic acid in

9 a use that would be consistent with a cosmetic

10 product, oxalic acid or oxalic acid derived from

11 oxalate esters.

12 So if it's insignificant, yeah, then I'm

13 not worried. If it's likely to be more

14 significant, then I would worry.

15 DR. BELSITO: Well, 10 percent would the

16 highest concentration, at least from the limited

17 use data we have right now, in a cosmetic product.

18 Bob, what is your sense for absorption

19 of oxalic acid versus a shorter chain acid?

20 DR. BRONAUGH: I don't know. It's

21 really hard to say. Oh, excuse me. It's really

22 hard to say. I guess, and not being a chemist, I





1 don't automatically know solubility properties. I

2 mean, it's certainly an acid; it's going to be

3 water soluble. I don't know to the extent that it

4 would penetrate through the stratum corneum if it

5 has no lipid solubility. But it depends. I don't

6 know the pKa of oxalic acid. I'm not sure what

7 that is.

8 DR. BELSITO: Well, we have in, let's

9 see, the table, the solubility is 1 gram per 7 mls

10 of water. And --

11 SPEAKER: That's very soluble.

12 DR. BELSITO: -- that's it.

13 DR. KLAASSEN: But then you have the --

14 DR. BELSITO: We don't have a --

15 DR. KLAASSEN: That's the dibutyl

16 oxalate.

17 DR. BRONAUGH: Right. Now there you

18 would start expecting some penetration.

19 DR. KLAASSEN: Yeah.

20 DR. BRONAUGH: In lipophilicity.

21 DR. KLAASSEN: I guess the point is this

22 is not a no-brainer. I mean, there's enough doubt




1 here, or at least in my mind.

2 DR. SNYDER: I guess my question goes to

3 why didn't the scientific literature review then

4 identify some of this information regarding the

5 renal toxicity? So did you search under the term,

6 all of those terms?

7 MS. ROBINSON: Mm-hmm. Yes, I did.

8 Yes, I did the search on the terms. And a couple

9 of the studies Halyna and I took out because there

10 wasn't enough information in the published report.

11 I can actually bring those back in.

12 DR. BELSITO: Well, what I'm hearing is

13 that, at least from both Dan and Curt, is that

14 they have enough concern that, again, the add-ons

15 are supposed to be no- brainers, and we've now

16 spent at least 10 minutes discussing whether

17 oxalic acid actually fits into this report, and

18 we're not seeing any evident cosmetic use of it.

19 So the no- brainer, you know, swore it would say

20 that we should eliminate oxalic acid and its

21 esters from this report.

22 DR. KLAASSEN: I agree. And just to put




1 this in perspective, some people, like myself, and

2 maybe us around this table have a job because of

3 the toxicity of oxalic acid. So in the 1930s, to

4 get a drug on the market what you had to do was to

5 show that it was effective. But then in the

6 1930s, when the sulphonamides came out, they

7 dissolved the sulphonamides in ethylene glycol.

8 And then we had a number of people that died,

9 especially children, from kidney injury. And the

10 toxicity really was due to the ethylene glycol

11 being metabolized oxalic acid. And as a result of

12 that, the FDA, Congress changed the laws for FDA

13 to get a drug on the market. You not only had to

14 show that it was effective, but that it was not

15 toxic. So this whole business around oxalic acid

16 is kind of, like, no small story in the history of

17 toxicology, for whatever that's worth.

18 MR. ANSELL: And, you know, I certainly

19 agree with these comments. I just want to throw

20 out that I can't actually find the reference for

21 it, but apparently it's used as a pH adjuster to a

22 concentration of about 5 percent in hair products.




1 So we'll follow up on that and see whether that

2 would have any bearing on that conclusion.

3 DR. BELSITO: So, to recap. We are

4 suggesting that the addition of oxalic acid to

5 this group is not a no-brainer and that we would

6 recommend that oxalic acid and the esters be

7 removed. Once that is done, if it's done, we find

8 this group to be insufficient for impurities, and

9 we would like impurities on a representative short

10 and long chain. The suggested ones were sebacate

11 and malonic or succinic acid. And then

12 subdividing those, we would like short- and long-

13 chain esters of a short- and long-chain acid,

14 impurities for those representative ones. And

15 then concentration of use. And the assumption,

16 also, is that when this document comes back to us,

17 that the NTP summary and that the information on

18 the dioctyl, diisopropyl, and diethylhexyl adipate

19 studies will be included in this report.

20 Is that where we're at?

21 SPEAKER: Mm-hmm.

22 DR. BERGFELD: Well, and use, because





1 they promised you use.

2 DR. BELSITO: I said that.

3 DR. BERGFELD: Did you say that?


5 DR. BERGFELD: Okay.

6 DR. SNYDER: Unless we're provided data

7 on oxalic acid regarding dermal absorption

8 toxicity.

9 DR. BELSITO: Yeah, I suppose that could

10 be done. But again, the boilerplate that we've

11 had for the decision to go ahead with additions

12 has been that it be a no-brainer. And that we

13 wouldn't need that additional data; that the data

14 was already there. I don't know.

15 DR. ANDERSON: I think the option would

16 always exist for any interested party to provide

17 data.

18 DR. BELSITO: Yeah, if there was data

19 provided on lack of absorption, then I guess that

20 the no-brainer part of it is if it gets absorbed,

21 how much and what would it do to the kidney. If

22 we see information that, you know, it's used




1 at.001 percent in a hairspray and it's not going

2 to get absorbed, then, you know, we might change

3 our minds. So I guess that we're considering

4 deleting oxalic acid unless we get information on

5 absorption and concentration of use in products

6 that it would be used in. But if it's open-ended

7 and we assume that it's going to be used in all

8 the same type of products as these other

9 dicarboxylic acids in concentrations up to 10

10 percent, we don't have any information, we'll

11 probably just remove it from the report.

12 SPEAKER: Lunchtime.

13 DR. BELSITO: It is 12:10. Be back at

14 1:10.

15 (Recess)

16 DR. BELSITO: Okay, welcome back. So,

17 we're back here at the PEGS. And at the last

18 meeting, as you know, the issue here is to reopen

19 it to get rid of this damaged skin restriction in

20 the conclusion. At the last meeting we had a

21 wonderful presentation on transepidermal water

22 loss and various skin diseases, including atopic



191 rabbits. So I got to where that was de rigueur, 2 that you didn't even write "rat" without putting 3 the species in front of it, essentially, ever. 4 DR. MARKS: Okay. So, I think we're 5 finished with these groups of ingredients. We can 6 issue a final amended safety assessment with "safe 7 as currently used in non- coloring hair care 8 products," with the editorial comments that we 9 discussed. 10 Next, sebacates. It's in the Pink. Let 11 me see. Book 3 under diisopropyl sebacate. 12 Okay. So, at the September '09 meeting, 13 Dr. Shank recommended that the report be expanded 14 to five additional ingredients and also that we 15 reorganize it, and so it was tabled. And so now 16 we're here looking at the revised report that's 17 been reorganized with new tables. And Ron, you 18 have the spreadsheet with the whole thing down 19 there. 20 So let's -- I think we have several 21 things. One is -- are the ingredients that are 22 included. Which ones -- are they okay? We have

201 genotox and carcinogenicity data, Tom, you need to 2 comment on. And then obviously other issues or 3 concerns. So should we go with the ingredient 4 list? 5 DR. SHANK: I have a strange suggestion. 6 I was considering -- or maybe we can consider 7 splitting this assessment into two parts: One for 8 the acids and the salts and one for the esters. 9 The acids all seem to be used as pH adjusters, so 10 the salts are very similar -- would be similar to 11 behave the same in terms of possible health 12 effects. The esters would be different. And I am 13 just suggesting that we might consider -- this is 14 a huge document -- splitting it for the acids as 15 pH adjusters and their salts and then a separate 16 assessment for the organic esters. 17 DR. SLAGA: I like that. 18 DR. SHANK: For the esters. 19 DR. HILL: Yeah, me, too. 20 DR. SHANK: Okay. 21 DR. SLAGA: I had concern that that's 22 too much here. And there's no doubt if it's a pH

211 adjuster -- 2 DR. SHANK: That's one thing. 3 DR. SLAGA: That's one thing. And we 4 know that's an extremely small concentration. 5 Anyway, good. 6 DR. SHANK: So after you've done all 7 this work. 8 MS. ROBINSON: Also, there are some 9 things missing as well because diethylhexyl 10 adipate was previously reviewed by CIR, so that 11 stuff needs to be incorporated as well. So it's 12 going to be an even larger document. 13 DR. MARKS: If that's been previously 14 reviewed we have to reopen it. 15 MS. ROBINSON: I gave you the original. 16 DR. MARKS: Yes. 17 MS. ROBINSON: Okay. 18 DR. MARKS: But I mean in terms of 19 protocol. 20 DR. SHANK: Yeah. 21 DR. BAILEY: If it's going to be added 22 then we -- basically you're reopening an existing

221 re-review I guess to add more substances. 2 DR. SHANK: Then you could take that 3 document, open it for re-review, and add these 4 other esters. Do it backwards. 5 DR. BAILEY: Okay. I think we're going 6 to have to think about this because -- 7 DR. SHANK: I have to see that database. 8 But if we've already reviewed. 9 SPEAKER: No, I agree with that, but -- 10 SPEAKER: We had three. 11 SPEAKER: Three. All right. 12 SPEAKER: And there's two reports. 13 MS. ROBINSON: It's diethylhexyl 14 adipate, dibutyl adipate, and diisopropyl adipate. 15 DR. BAILEY: So those are logical to 16 group, I think, and then you add the other esters 17 into it. And then you've got the acids and the 18 salts as a separate document. They're chemically 19 somewhat different. So -- 20 DR. MARKS: What were those again, 21 Valerie? Dihexyl -- 22 MS. ROBINSON: Diethylhexyl adipate,


231 dibutyl adipate, and diisopropyl adipate. 2 DR. MARKS: Comments about -- it 3 certainly seems logical, Ron. 4 DR. BAILEY: Was the only missing 5 information the genotox that was asked for in 6 September? Because I think that was provided, 7 wasn't it? 8 DR. SHANK: We have genotox on two of 9 the sebacate esters, not mutagenic. We have geno 10 -- immunogenecity data on diethyl malonate, 11 negative; succinic acid, negative; glutaric and 12 adipic acids, negative; diethylhexyl adipate, 13 negative; dioxy-nonyl-adipate-2, 1-adipate ester 14 azelaic acid, negative. All of the mutagenicity 15 data are negative. But there's not -- 16 SPEAKER: It's skimpy carcinogenic 17 (inaudible). 18 DR. SHANK: There are lots of missing -- 19 nothing on oxalic acid or the oxalates. 20 MS. EISENMANN: And actually, NTP has -- 21 it's negative in salmonella. 22 DR. SHANK: Which?

241 MS. EISENMANN: According to the NTP, 2 oxalic. 3 MS. ROBINSON: Oxalic. 4 MS. EISENMANN: Published in Halworth, 5 et al., 1983. It's not in there yet. 6 DR. SHANK: Okay. 7 DR. BAILEY: Okay. So we have more 8 information that's going to be necessary? 9 MS. EISENMANN: Yeah. There's a lot of 10 information that's still not in this report, 11 including the CIR reports because there's an NTP 12 bioassay on the diethylhexyl adipate. 13 DR. SLAGA: Should we table it? 14 DR. MARKS: Well, that's the next 15 suggestion. 16 DR. SLAGA: I mean, we're tabling it in 17 reality anyway. 18 MS. EISENMANN: Well, and you don't have 19 the concentration of use information for any of 20 the new ingredients either. That hasn't been done 21 yet because I didn't know they were going to be 22 added.

251 DR. SHANK: Well, if we could discuss 2 first should we split it up or -- 3 DR. MARKS: Well, I think that's it. I 4 think we should -- I guess it'll come down to 5 table with what is the action we want to take. 6 And it seems like splitting it is a very 7 reasonable way to approach this. 8 DR. SLAGA: And putting the appropriate 9 data into whatever is split. 10 DR. HILL: This is whose report? 11 MS. ROBINSON: It's my report. 12 DR. SLAGA: Valerie. 13 DR. MARKS: Did John, Carol, Ron -- Tom, 14 I got the sense you like the idea of splitting it. 15 It certainly makes sense. 16 DR. BAILEY: The (inaudible) thing I'm 17 thinking of is that with the glycolic acid, we did 18 the glycolic acid and salts and esters. So there 19 we kept it altogether. I can see the logic 20 between splitting; I just wonder what is the most 21 efficient way to do this. 22 DR. MARKS: Or do we have one document

261 where essentially it's two groups? 2 DR. BAILEY: Right. I guess at the end 3 of the day the information that's going to be 4 informing the safety here will be from the acids 5 and the esters, right? I mean, it's not going to 6 be a separate set of data for the acids versus a 7 separate set of data for the esters? I mean, I'm 8 just having a hard time visualizing how this would 9 be split and how CIR staff, you know, this is a 10 significant burden, too. So I'm just trying to 11 think of efficiencies here that might work. 12 What do you guys think? 13 DR. SLAGA: Could we have it as two 14 parts then where you deal with the pH adjusters, 15 the acids, and then follow it by the esters in the 16 same document? 17 DR. SHANK: The uses for the acids are 18 quite different from the uses of the esters. And 19 that's where I would like to split them. But we 20 don't have a whole lot of use information either. 21 SPEAKER: Yeah. 22 DR. SHANK: We have to take the whole


271 thing, weight of evidence, to make a decision on 2 these. But if you look at what information we 3 have, at least what's in this report, there's not 4 very much on any one of them. And nothing on the 5 lead ingredient. 6 DR. BAILEY: But I think it's a 7 reasonable proposal. Maybe we can -- you guys can 8 present it tomorrow and then have a discussion 9 with the other team and see. 10 DR. MARKS: Are we going to use data do 11 you think, Tom and Ron, from the acids that 12 support the safety of the esters and vice versa? 13 If we're going to do that, then it seems like it 14 would make sense to have it all together, but 15 split. We've done that before where we've taken a 16 group of ingredients and split them in the same 17 report. 18 DR. BAILEY: Because it would be 19 duplicating a lot of material to go into the 20 report. If you're going to use ester data to 21 support the acid section and vice versa -- 22 DR. MARKS: Right.

281 DR. BAILEY: -- then you're basically 2 going to have to duplicate it, you know, between 3 the two reports, which is okay. But, again, 4 thinking of efficiency and -- 5 DR. SHANK: I just don't see using ester 6 data to support the safety of the acids. 7 DR. HILL: Me neither. 8 DR. BAILEY: Well, the metabolism of 9 esters will generate the acids. 10 DR. SHANK: Yeah, but the acids are used 11 differently. They're used as pH adjusters in the 12 formulation process. That's different from having 13 metabolic generation of the acids. 14 DR. BAILEY: No, I can (inaudible) that. 15 DR. SHANK: Yeah, I can handle it if 16 it's all in one, but I think it's -- I think it's 17 easier to split. 18 DR. HILL: I fully support your 19 proposal. 20 DR. SHANK: Okay. Thank you. 21 MS. WEINTRAUB: Is the body of evidence 22 that different or isn't it some other (inaudible)?

291 DR. HILL: You would be using acid data 2 to support the ester data, but probably not the 3 other way around. I can't see any place where 4 that would be the case. So you would have to 5 reference the acid reports, probably repeatedly, 6 but I don't see the downside of that. 7 DR. MARKS: Well, to me it would be nice 8 then to have a report where you would start off 9 and say we're going to discuss the acids first. 10 The first part of the report would be all the 11 acids. And the reason it's split is because of 12 use and their salts. And then the second part, 13 the esters, be very clear they have different 14 uses, but we're going to use some of the acid 15 toxicology to support the safety esters. And 16 again, it's all in one report so you don't have to 17 go back. 18 DR. BAILEY: That's kind of what I'm 19 thinking. 20 DR. MARKS: Yeah. 21 DR. BAILEY: Do you know how this is 22 actually going to look? And Carol -- I think once

301 Carol gets the concentrations of use, that might 2 help us, too, sort those out in a more -- in a 3 cleaner way for one report. Because they are 4 going to talk back and forth. 5 DR. MARKS: There's no question they're 6 going to be split. I think the only issue is are 7 they going to split -- be split into two documents 8 or are they going to be in one document and split 9 within the one document? And I guess the question 10 is how unwieldy that is, but if you're going to 11 use any ester document, a lot of references to 12 things in the acid document, it might be well to 13 keep it all together. 14 DR. BAILEY: In thinking about the 15 purpose of these reports, too, is important 16 because this communicates to users, the industry, 17 and others what's expected, you know, the basis 18 for safety and any conditions that might be 19 imposed, and that those are probably more 20 efficiently communicated in one document than two. 21 DR. MARKS: Yeah, that's -- 22 DR. HILL: I would just echo Tom's view


311 that the purposes of use are really quite 2 different. The biohandling of the compounds 3 should be expected to be quite different. Even 4 though we expect the esters to be biotransformed 5 into acids, systemic availability situations 6 should be quite different between the acids and 7 salts as opposed to the esters. And so I'm 8 thinking the conclusion at the end could get quite 9 unwieldy based on that vast difference in the way 10 these things are used. And so I think it would 11 end up -- if you had two documents, I mean, they 12 could be published back- to-back. But if you had 13 two documents you would have, I think, cleaner 14 conclusions at the end. 15 DR. MARKS: I guess that's assuming that 16 you're going -- if you get all the data in that 17 you can publish them back-to-back. 18 DR. HILL: Publish them back-to-back and 19 wait on the one. 20 DR. MARKS: You can put out an 21 insufficient and sort of push it to get it all 22 together. But again, I think that's -- we'll see

321 what the other team -- that's not a huge issue, 2 one versus two documents. The most important is 3 splitting, isn't it? 4 DR. SHANK: Well, if you split them -- 5 put them in one document or two -- I don't care. 6 It may be that Dr. Hill's absolutely farsighted 7 enough that when we come to the conclusion, the 8 conclusion will be so complex that we'll decide to 9 take the two parts and put them into two different 10 documents. 11 DR. SLAGA: Well, but look at what we 12 have and what kind of data there is. You know, 13 there's really probably not going to be much of a 14 problem. The conclusion is going to be probably 15 very simple. I mean, that's what I would predict. 16 DR. BAILEY: I would expect that. You 17 could say hypothetically that the acids and salts 18 are safe for use, you know, as a pH-adjusting 19 agent. That concentration is up to use -- 20 such-and-such a use and the esters would be some 21 variation on that. So, I wouldn't envision a 22 complex -- but, you know, if we get to that point

331 and they are complex then we can think about 2 splitting it up then. And it probably would be 3 fairly easy to do. Don't you think? 4 DR. SLAGA: Okay. We would wait until 5 we see all the data. 6 DR. BAILEY: Right. 7 DR. MARKS: So I'll move that we table 8 this. Does that sound good? Ron, Tom, Ron? 9 DR. SHANK: We don't want to go through 10 the report itself? Wait till we get a new 11 version? 12 DR. MARKS: And so we'll proceed forward 13 with the idea that we're going to split the acids 14 and their salts from the esters. We're not sure 15 yet whether this is going to be one or two 16 documents. We tend to be leaning towards one 17 document, at least to begin with. 18 DR. BAILEY: With the possibility of 19 going to two. 20 DR. MARKS: And in this process we've 21 got to reopen three ingredients. Is that not 22 correct?

341 DR. SHANK: And those are all esters of 2 adipic acid? 3 MS. ROBINSON: Yes. 4 DR. SHANK: The three ingredients? 5 DR. SLAGA: Those were all safe, weren't 6 they? 7 MS. ROBINSON: Yes. 8 DR. MARKS: And in that long list in the 9 beginning, the dihexyls, where under the subject? 10 Can you -- adipate should be down towards the 11 middle to the end. Is that right, Valerie? We 12 had the dibutyl and diisopropyl? 13 So it's dihexyl adipate? Is that -- 14 MS. ROBINSON: Diethylhexyl adipate. 15 It's the third from adipic acid. 16 DR. MARKS: Adipic acid. I'll tell you 17 what. I'll get that from you later. 18 DR. SHANK: Diethyl hexyl? 19 DR. MARKS: Diethyl hexyl. 20 DR. SHANK: What were the other two? 21 DR. MARKS: And then there was dibutyl. 22 DR. SHANK: Dibutyl adipate?


351 DR. MARKS: Adipate. That's on the next 2 line. And then diisopropyl. Is that correct? 3 MS. ROBINSON: Yes, that's correct. 4 DR. MARKS: Diisopropyl. Where is that? 5 Diisopropyl. Okay. There we go. Adipate. So 6 these three. Okay. 7 Anything else? 8 DR. HILL: As you started to say, we 9 have a statement -- sorry, I'm paging around -- 10 about the unavailability of physical and chemical 11 properties. And I was wondering if the -- this 12 might -- Kevin's not in here, is he? 13 MS. ROBINSON: No. 14 DR. HILL: If the Beilstein database had 15 been searched for that. 16 MS. ROBINSON: The Beilstein? 17 DR. HILL: Beilstein, B-E-I-L-S-T-E-I-N. 18 DR. BAILEY: All of us old chemists know 19 what that is. 20 DR. HILL: It used to be all dusty 21 shelves in libraries. Shelves that went on and on 22 and on and on. But, yeah. Because you might find

361 that information. And we are looking at a lot of 2 ingredients -- at least what's in here -- we're 3 going to be interpolating and in some cases 4 extrapolating. And that might be highly relevant. 5 MS. ROBINSON: Thank you. 6 DR. MARKS: Is there anything in this 7 long list here on -- Tom or Ron -- that need to be 8 deleted at this point? Because we didn't actually 9 go over the individual ingredients like we've done 10 in the last. We've gone down here -- is there 11 anything on any of these that just don't make 12 sense? 13 DR. SHANK: Well, under malonic acid, 14 diethyl malonate toxicity data are given in the 15 report, but it's not one of the ingredients in the 16 title. So, we should discuss should we leave that 17 in because it is malonic acid ester and there are 18 data? But it's not an ingredient. But it might 19 help us make decisions on the other -- the one 20 ester that is there is the diethyl. 21 DR. HILL: Well, it could be included 22 for consideration without having it be one of the

371 list of ingredients, couldn't it? I mean -- 2 DR. SHANK: But I think we should 3 identify it as it's here, but it's not an 4 ingredient. But we're using those data. 5 DR. HILL: And since Dr. Bailey is here, 6 this is kind of a dictionary question. In looking 7 at the structure she has, "There are two different 8 flavors of diisooctyl. One is an adipate and one 9 of the others --" 10 DR. BAILEY: What page are you on? 11 DR. HILL: Well, okay, if you go to the 12 tables, that's -- no, not the tables, the figures. 13 Figures come after the tables. There's a pink 14 page. 15 DR. BAILEY: What page? 16 DR. HILL: So I'm looking at the very 17 bottom of page 9, diisooctyl adipate. Actually, 18 why is it on there twice? 5L and 5P seem to be 19 the same, huh? 20 DR. BAILEY: 5L and 5P seem to be the 21 same, huh? 22 DR. HILL: They seem to be the same.

381 But that wasn't the question I had. On page 14, 2 we have a diisooctyl sebacate. And that's 3 actually a different diisooctyl group in terms of 4 where the hydroxyl is attached. 5 DR. BAILEY: That's 7H that you're -- 6 DR. HILL: Yeah. Well, actually, yes, 7 7H, the isooctyl group is different than it is -- 8 they're both isooctyl, but the group is different 9 on adipate versus sebacate. And that's probably 10 just an artifact of the dictionary and the 11 ingredients that were actually being used. But I 12 was puzzled by that because it remains the same, 13 but the structure is quite different. 14 DR. BAILEY: We'll look that up. 15 DR. HILL: Okay. 16 DR. SHANK: As long as we're on the 17 figures, Figure 3E -- I think it's 3E, on page 4 18 -- it says diethylhexyl adipate. Isn't that 19 diethylhexyl succinate? 20 DR. BAILEY: It kind of looks like it. 21 MS. ROBINSON: Sorry, Dr. Shank, which 22 --


391 DR. SHANK: It's page 4 of the figures, 2 Figure 3E. The title says -- the name of the 3 structure says diethylhexyl adipate. In fact, 4 it's diethylhexyl succinate. 5 DR. HILL: And while we're there, this 6 is a formatting question, but one I encounter 7 generally. If you have a chemical name like 8 diethyl succinate, there's no reason to use 9 uppercase letters. But I'm assuming that 10 uppercase letters are frequently used in the 11 reports because they're dictionary ingredients. 12 That's where it comes from. So if they're 13 dictionary ingredients, I'm guessing in the 14 figures, they ought to keep that same formatting 15 using uppercases. 16 DR. HOWARD: I think we made the change, 17 and Halyna can speak to this as well, that within 18 the report we weren't going to capitalize 19 ingredient names anymore. 20 DR. BRESLAWEC: Yeah. We're getting a 21 lot of comments from the International Journal of 22 Toxicology when we're publishing our reports not

401 to use capitalized names. So we will use the 2 capitalized names when we're referring 3 specifically to the INCI name, but we have to go 4 back and rechange them to lower cap at the point 5 of publication. So we're trying to avoid 6 capitalizing them when we can. Does that make -- 7 DR. SHANK: While we're on that 8 journal's formatting, whatever happened to this 9 introductory summary that I had adapted to and 10 everybody else said they're great in all the 11 reports. I think kojic acid is the only one that 12 has this. Where are we on that? Are we going to 13 have them or not? 14 DR. BRESLAWEC: We like the approach. 15 We hope to introduce the approach. Many of the 16 documents that you see now have been in 17 preparation for a while and so it's not being 18 implemented kind of across the board from this 19 point on. It will be implemented as new documents 20 become available. 21 DR. SHANK: Okay. The same thing with 22 the reference -- citing references in the text?

411 DR. BRESLAWEC: Unfortunately, yes. 2 DR. SHANK: That's the same? That's in 3 progress? 4 DR. BRESLAWEC: That is in progress. 5 DR. SLAGA: And the same way with the 6 abstract (inaudible), too? 7 DR. BRESLAWEC: That also is in 8 progress. We just have different documents that 9 are different phases of preparation. And we made 10 a decision to implement all the changes on new 11 documents as they begin rather than saying, okay, 12 everybody, change the format of the things that 13 you're working on. So it will be -- it will 14 continue to be confusing for at least six more 15 months, if not longer, for other reasons. 16 DR. MARKS: Any other comments? So 17 we're going to table this list of ingredients for 18 more data. We're going to recommend that the 19 acids and salts be split into one group, the 20 esters in another group, which presumably at this 21 point will be one document with the option of 22 becoming two documents as we proceed through.

421 We're going to reopen the three esters that are in 2 this document that have already been reviewed and 3 the Expert Panel found to be safe: The 4 diethylhexyl adipate, the dibutyl adipate, and the 5 diisopropyl adipate. 6 Is that it? Sound good? 7 DR. SHANK: Mm-hmm. 8 DR. MARKS: Okay. 9 DR. BAILEY: One thing regarding the 10 dictionary and naming conventions. The ethylhexyl 11 and isooctyl, you know, I think are -- I think for 12 a while they were named as isooctyl and I think 13 they're called ethylhexyl now. But we'll follow 14 up on that and find out what the convention is in 15 the dictionary just for consistency, even though 16 it may not be rigorous UPAC or other naming 17 conventions. We do have a shorthand that we use 18 in the dictionary and I think since our audience 19 is the cosmetic stakeholders, industry, and 20 others, then I think we need to make that as 21 consistent as we can throughout. 22 DR. HILL: Yeah. And I'm not suggesting


431 that if that's been the state of the art and 2 that's what people have on their labels that any 3 change would necessarily be needed. But then we 4 maybe just need to point that out, that there is a 5 difference in the document, which I think we'd be 6 doing anyway because if hydrolysis is occurring, 7 we're generating different alcohols. 8 DR. BAILEY: Right. No, I fully agree. 9 DR. HILL: The shorthand is the 10 shorthand. 11 DR. BAILEY: Right. 12 DR. MARKS: Next we're going on to the 13 polyethylene glycols, the PEGs. It's in Pink Book 14 1. We have some new information. 15 So as you recall, in December of 2008, 16 we reopened this safety assessment and we then 17 proceeded to issue a tentative amended safety 18 assessment of PEGs. In the September meeting this 19 year, we heard a presentation concerning trying to 20 deal with the issue of damaged skin and developing 21 a margin of safety so that we could feel 22 comfortable that PEGs would be safe where there is

441 a significant amount of compromised skin or 2 damaged skin. The wording, I think, we'll work 3 on, also, and not have the possibility of renal 4 toxicity. 5 So, I'll open it up for discussion. One 6 is dealing with that wording of damaged skin and 7 the other -- maybe that will disappear other than 8 in the summary or the discussion -- and the other 9 is the margin of safety calculations. And then we 10 have some new use and concentration data that we 11 were just given. 12 So, Ron? 13 DR. SHANK: Where do you want to start? 14 With the conclusion? 15 DR. MARKS: Yes. 16 DR. SHANK: Okay. I would use the old 17 conclusion, but delete the caveat "on damaged 18 skin." So it's safe as used because the margin of 19 safety analysis, I think, is reasonable and offers 20 sufficient safety for cosmetic use that we don't 21 have to have a caveat on "use on damaged skin." 22 SPEAKER: I agree.

451 DR. MARKS: Tom, you agree with that? 2 DR. SLAGA: Mm-hmm. 3 DR. MARKS: Ron? 4 DR. HILL: Mm-hmm. 5 DR. MARKS: Comments? 6 SPEAKER: (inaudible) 7 DR. MARKS: So safe as used. Now, do we 8 even have to get into -- we obviously somewhere in 9 the discussion have to deal with the previous 10 conclusion and why it's been changed. Obviously, 11 the margin of safety makes us change. Do we even 12 need to wordsmith "damaged skin" or just say that 13 we've deleted that because now we have a margin of 14 safety? 15 DR. SLAGA: Well, that could be 16 discussed, as you were saying in the discussion. 17 Previously it was stated as caution related to 18 damaged skin, but now we're eliminating that 19 because of the margin of safety. 20 DR. SHANK: I think it would be helpful 21 to have in the discussion at least one paragraph 22 on the panel's analysis of what we meant by

461 "damaged skin." The studies that were done to 2 look at absorption through damaged skin, which is 3 really a barrier of compromised skin. 4 DR. MARKS: Yes. I kind of -- that's 5 what I used as the rewording, call it barrier of 6 compromise and put it in that context then in the 7 discussion. Because obviously with the burn 8 patients we had total loss of the epidermis along 9 with significant portions probably of the dermis. 10 So it's a much different situation than what we're 11 dealing with in a barrier compromise. 12 DR. SHANK: Right. It's a major change 13 in the old conclusion, in my opinion. And I think 14 that needs to have at least a paragraph in the 15 discussion as to why we're making that change. 16 DR. MARKS: Okay. 17 DR. BAILEY: I think you want to be 18 cautious in defining damaged skin because that's 19 almost a case-by-case kind of consideration. 20 DR. MARKS: Right. I think we have to 21 mention that because that's what we deleted. 22 DR. BAILEY: Absolutely.


381 described as a surfactant the way it's written, 2 which is not the case, and so that's clear in some 3 spots but ambiguous or misleading in others and 4 that I've noted those, so. 5 DR. BERGFELD: Curt, anything? Paul? 6 Dan? Ron? Tom? Jim. 7 DR. MARKS: No, I'd just reiterate the 8 editorial comments, which already you'll find in 9 our notes. 10 DR. BERGFELD: Okay. Any other 11 discussion? Rachel? Call the question. All 12 those in favor, then, please raise your hands. 13 Unanimous. Thank you. No abstainers. 14 We're moving on to the next groups of 15 reports, advancing, and the first green report is 16 "Sebacates" by Dr. Belsito. 17 DR. BELSITO: Yes. We looked at this 18 document. This is the first time we're looking at 19 it. We received abundant information, and we'd 20 like to thank PCPC and all the other contributors 21 for getting that to us. 22 We feel that probably it is sufficient

391 information to go ahead with a safety assessment. 2 However, some of it was just to summarize to us in 3 the diesters HPV test plan, and so my team 4 recommended that we table this and get the actual 5 data from the HPV reporter, at least a little bit 6 more information, specifically focusing on 7 genotoxicity and carcinogenicity. 8 DR. MARKS: We concur with that to table 9 it. In addition, we wanted to firm up what the 10 actual ingredients that we were going to review. 11 There are potentially five other dicarboxylic 12 acids to be included. And then, lastly, just 13 alert Don and the other panel members as to 14 whether or not we're going to put a limit on 15 diethyl sebacate with a concentration of less than 16 or equal to 1.5 percent, which was in the RIPT, 17 and there's a lot of case reports which alert that 18 this is a sensitizing compound. 19 DR. BERGFELD: So, is there a second to 20 table? 21 DR. MARKS: Yes. 22 DR. BERGFELD: There's no discussion

401 with a table. All those in favor of tabling until 2 the next meeting please raise your hands. Thank 3 you. This particular ingredient is tabled till 4 the next meeting. 5 Can we do it by next December -- by 6 December 7th? 7 DR. ANDERSEN: Well, since I want to get 8 this finished this year and that's our last 9 opportunity, the answer is yes, we can do that in 10 some fashion. 11 DR. BERGFELD: Okay. 12 DR. ANDERSEN: We'll figure it out. I 13 also want to let you know that the kind of 14 information that both Dr. Belsito and Dr. Marks 15 presented before the vote to table will be 16 included in the announcement to give all 17 interested parties a full heads-up as to just what 18 the issues are. So, we will capture that and 19 include it while the formal push is to gather 20 those more expanded genotox studies. The rest of 21 it -- if anyone has additional data, that would be 22 a good time to provide it.

411 DR. BERGFELD: I wonder if you would 2 just go back over the procedures and re-enlighten 3 us. Since we did away with the insufficient data 4 announcement and we move either to a tentative 5 final or to insufficient data, when we make an 6 action like table an ingredient group that it 7 automatically goes out in an announcement of why 8 it's tabled? 9 DR. ANDERSEN: Yes. 10 DR. BERGFELD: Okay. 11 DR. ANDERSEN: Yeah, it seems only fair 12 to the public to let them know what the panel's 13 thinking. Just capturing that the discussion was 14 tabled doesn't convey a heck of a lot of 15 information. 16 DR. BERGFELD: Okay. 17 DR. ANDERSEN: So, we've been expanding 18 on what was the basis for the table so that 19 everyone understands. 20 We have not abandoned fully the 21 insufficient data announcement. If we do have a 22 circumstance in which there are clearly inadequate


421 data, then we must make that announcement. What 2 we have abandoned was the old procedure of issuing 3 an informal data request with the target of well, 4 we think you guys probably have this data, whoever 5 "you guys" is in that sentence, and we'd like to 6 give you a chance to submit it. In the interest 7 of proceeding smartly to completion, we've said 8 you're going to get one chance. It's a formal 9 insufficient data announcement. If we don't get 10 the data, we're going to issue a tentative with an 11 insufficient data conclusion. Part of that 12 thinking is that we've announced a year ahead of 13 time which things we're going to be working on. 14 So, if folks had data in their files back home, 15 they had a year to get it in before we even wrote 16 the literature review. So, again, the thinking is 17 let's streamline this as much as possible, but we 18 do have that opportunity to issue an insufficient 19 data announcement if it's warranted. 20 DR. HILL: And I would just say in our 21 discussion yesterday that we did talk about 22 concerns with appropriateness of read-across data

431 in some of the HPV reports in terms of the 2 bio-handling for dermal exposure. So, that was a 3 particular -- I think probably some gaps. 4 DR. BERGFELD: Jay, I wonder if you 5 would carry on the conversation that Alan just had 6 and tell us, then, what your responsibilities 7 would be after we have tabled this. What is your 8 step? What is your next step? 9 DR. ANSELL: It's our intent to go back 10 and work with the CIR to see what level of detail 11 is possible in terms of all the summaries of the 12 mutagenicity studies. Because of the nature of 13 the HPV program, the data is property; 14 conclusions, not so. But the actual studies are 15 mutually owned by the people that ran it. So, the 16 question comes: How much detail can we get short 17 of becoming a member of the consortium? And we 18 will work with Alan to determine how much detail 19 we can get. 20 DR. BERGFELD: The second question I 21 have of you is when we make our annual report on 22 what we will be reviewing this particular year,

441 like 2010 -- and as Alan said they've heard and 2 they didn't supply us -- do they really hear? Do 3 you have a point person in these industries to say 4 we need this from you? 5 DR. ANSELL: We have the new CIR 6 Scientific Support Committee, which is taking on 7 issues like this. We had a meeting in fact just 8 this week, within the last few days, in which the 9 discussion about the survey use -- the use and 10 concentration survey which we conduct where it 11 needs to be done relative to the process. So, 12 we're working closely with CIR to ensure that. 13 DR. BERGFELD: Okay. 14 DR. ANSELL: In this particular case, I 15 will point out that it was not the lack of data. 16 Rather, it was the amount of detail associated 17 with what we provided. 18 DR. BERGFELD: Thank you. Thank you. 19 DR. ANDERSEN: Good point. 20 DR. BERGFELD: All right, we're going to 21 move on, then, to the next ingredient, which would 22 be the PEGs, Dr. Marks.

�


TEAM�MEETING�MINUTES�ON�SEBACATES��DR.�BELSITO’S�TEAM�

7 DR. BELSITO: If you could do that, let

8 us know because then it would help. I mean, I

9 don't think we're going to reopen the report. The

10 question is how to wordsmith the discussion

11 regarding this.

12 Okay. Anything else on the bromates?

13 Okay. So we're moving to the sebacates. How do

14 you pronounce that?

15 DR. ANDERSEN: We had a short discussion

16 on the other team and nobody knew how to pronounce

17 it.

18 SPEAKERS: Sebacates.

19 DR. BELSITO: Sebacates.

20 SPEAKER: What color?

21 DR. BELSITO: Green. It's with the

22 kojic acid.

198

1 SPEAKER: Green one.

2 DR. BELSITO: Okay. Okay, so this is a

3 first for us. A SLR, so it's in green along with

4 kojic acid.

5 And we've gotten some new data. And

6 again, this was one of the reports, like kojic

7 acid, that was sort of formulated in, hopefully,

8 the new CIR approach to doing documents, which I

9 think we already discussed with kojic acid that we

10 liked. And so now we're just looking at this data

11 and deciding what we need.

12 On Table 1 on page 42 and 43, there were

13 just a couple that I thought needed to be

14 amplified like dioctyl sebacate is an organic

15 compound. That's the definition. See Structure.

16 DR. LIEBLER: The middle of page 32

17 you're talking about?

18 DR. BELSITO: No, top.

19 MS. BECKER: Top of page.

20 DR. BELSITO: And then on page 33, the

21 same thing with dodecanedioic acid is an organic

22 compound.

199

1 DR. ANDERSEN: Coagula extract is an

2 extract of coagulum.


4 DR. ANDERSEN: This is the dictionary

5 we're talking about.


7 DR. ANDERSEN: It is what it is.

8 DR. BELSITO: So straight out of the

9 dictionary?

10 DR. ANDERSEN: Yes.

11 DR. BELSITO: Because all the others say

12 it's the diester of isostearyl alcohol and sebacic

13 acid.

14 Okay. Just questioning.

15 DR. LIEBLER: You know, the structures

16 in this table, I realize it's tough, but the

17 structures are just about unreadable. And I think

18 -- I don't exactly know how you do these, but if

19 you can perhaps paste in better quality structures

20 from something like ChemDraw or ChemOffice.

21 MS. BECKER: Yeah, these were done in

22 ChemDraw.

200

1 DR. LIEBLER: Well, you've got the

2 world's tallest carbonyls.

3 MS. BECKER: I don't have steady hands.

4 DR. LIEBLER: There's a bug, so if you

5 did it in ChemDraw and it looked right, then

6 there's a problem with cutting and pasting or

7 something. But that just needs to be fixed

8 because they're unreadable.

9 MS. BECKER: Okay. Okay.

10 DR. ANDERSEN: All right. And this is a

11 perfect opportunity to get some feedback from you

12 on -- flip back to the kojic acid report, since

13 it's in the same document, real quick. My own

14 personal preference, which hasn't succeeding in

15 posing yet, my own personal preference is that you

16 get more out of showing the stick figures.

17 DR. SNYDER: Yes.

18 DR. ANDERSEN: A better understanding of

19 what the heck this molecule really looks like in

20 its length, especially if your eyes aren't good

21 enough to figure out if that's an 11 or a 17 in

22 the little side script in the "formula." So


201

1 that's the direction that I would like to go.

2 And frankly, since that looks hugely

3 awkward when you try to put it in tables, I'd pull

4 it out of the table.

5 DR. BELSITO: Right, as in figure 7.

6 Right.

7 DR. LIEBLER: The figure is fine and

8 these figures for the kojic acid compounds look

9 just fine.

10 SPEAKER: What page is that on?

11 DR. LIEBLER: 55.

12 MS. BECKER: 55.

13 SPEAKER: (off mike) the kojic ones.

14 DR. SEIDMAN: Alan, what are you

15 suggesting gets pulled out of the table?

16 DR. ANDERSEN: The figures.

17 SPEAKER: So all the figures.

18 DR. BELSITO: The figures. Do it as a

19 figure.

20 SPEAKER: They don't fit.

21 SPEAKER: So do it as a separate (off

22 mike)?

202

1 DR. BELSITO: Yes.

2 SPEAKER: Okay.

3 DR. SEIDMAN: Which, I might point out,

4 is how Valerie had it in the first place.

5 SPEAKER: (off mike) acid.

6 DR. SNYDER: What are we going to title

7 it?

8 DR. BELSITO: Basic acids and salts and

9 esters as used in cosmetic products. So basic

10 acids and other related dicarboxylic acids and

11 their salts and esters as used in cosmetic

12 products. You don't like that sound?

13 DR. SNYDER: No, I'm just curious.

14 MR. RE: If you would like to see the

15 stick figures, just turn to the HPB.

16 DR. BELSITO: Yeah. Okay. On page 3,

17 this West Germany reference. First of all,

18 there's not even a reference. It just says

19 amongst Germany that's got to be at least 20 years

20 old. So I would say that unless we have some

21 update from the EU or from the current German

22 state, we delete that.

203

1 Page 4, the azelaic acid, 20 percent is

2 approved by the FDA. It's a topical cream for the

3 treatment of mild to moderate acne. There is also

4 a 15 percent gel for the treatment of rosacea.

5 DR. SNYDER: And along those lines,

6 that's not -- transillic acid is not listed in the

7 use table.

8 SPEAKER: I thought it was.

9 MS. ROBINSON: It is. It should be.

10 DR. SNYDER: I thought it was at the

11 very end.

12 MS. ROBINSON: Yes. It's on page 39,

13 all the way at the bottom it starts.

14 DR. SNYDER: I'm looking at the new use

15 (off mike).

16 MS. ROBINSON: Oh, it's in the actual

17 tables.

18 DR. BELSITO: Page 39.

19 MS. ROBINSON: Yeah, at the end of the

20 actual document.

21 SPEAKER: At the bottom.

22 DR. BELSITO: Azelaic acid shaving care.

204

1 DR. SNYDER: Oh, okay. I was looking at

2 (off mike).

3 DR. BELSITO: No.

4 DR. SNYDER: Okay. Never mind.

5 DR. BELSITO: Page 7, under Acute

6 Toxicity, the dibutyl and sebacate and azelaic

7 acid. I thought that the last couple of sentences

8 in both of those paragraphs -- while dibutyl is

9 not currently used, it would unlikely cause acute

10 toxicity, and the rest of that paragraph. And

11 then these data indicate that azelaic acid is not

12 highly toxic (off mike) oral. Shouldn't those be

13 in the discussion rather than here? Or are we

14 making -- again, I guess we're changing the format

15 so this -- is it likely renal?

16 MS. ROBINSON: I can move it to the

17 discussion if it's an easier read. But what do

18 you think, Brenda?

19 DR. ANDERSEN: I think what we've been

20 doing is trying to calibrate how it is we handle

21 giving the reader a sense of the import of the

22 section.


205


2 DR. ANDERSEN: This goes much further

3 than we did in the examples for kojic acid. So

4 the question is what's your level of comfort with

5 that? Kojic acid was more of an attempt simply to

6 summarize what data you'll find in the following

7 paragraphs. This says these data are gone because

8 they are. But if you want to reserve any such

9 statements for the discussion, we can do that. We

10 wanted to push the envelope a little bit and see

11 what your reaction was.

12 DR. SNYDER: I like it better in the old

13 report where it was italicized right up front

14 rather than here it's kind of --

15 DR. BELSITO: Buried.

16 DR. SNYDER: -- buried at the summary

17 statement or discussion-like statement instead of

18 being a summary-like statement there.

19 DR. SEIDMAN: May I suggest something?

20 I think revisit this in just a few minutes when

21 you get to the tables. The new tables we're

22 throwing out there as floaters or trial balloons,

206

1 so you might want to just consider this. Revisit

2 it in just a few minutes when you look at the

3 summary tables because you might want to think

4 about putting summary tables in the individual

5 sections instead of a summary statement or you

6 might want a combination. So you can discuss this

7 further, of course, now. But you might just want

8 to think of shelving it for just a few minutes

9 until you see the tables in 5 (off mike).

10 DR. BELSITO: Okay. We can do that.

11 Page 10.

12 DR. SNYDER: Well, in that same area, I

13 prefer to say the studies that reported NOEL are

14 less than 4,000 milligrams rather than "CIR

15 concluded." We had a couple things CIR concluded,

16 CIR determinate. I think we (off mike).

17 MS. ROBINSON: What paragraph?

18 DR. SNYDER: On page 7, (off mike). The

19 third line in the first paragraph there where it

20 says, "CIR concluded that the study supported (off

21 mike)." Say, "The study supported NOEL."

22 MS. ROBINSON: Okay.

207

1 DR. SNYDER: And then down at the next

2 one under azelaic acid with rat and rabbit, CIR

3 determined the maximum tolerated dose. It should

4 just say, "Based on the reported endpoints of

5 animal deaths, the maximum tolerated dose (off

6 mike)."

7 DR. BELSITO: On page 10 on the Mingrone

8 Study 1083, were the ends given? There were no

9 ends.

10 DR. ANDERSEN: A perfect segue to let's

11 talk tables. What Brenda was referring to earlier

12 was that there had originally been captured Table

13 5 that summarized at least one study. And not to

14 put words in Brenda's mouth, but the idea of

15 having a full picture of which species, what dose

16 levels, how many animals, is what she would like

17 to see. So she went ahead and made tables for

18 both Smith in '53 and Mingrone in whatever year.

19 And those tables 5A and B or whatever --

20 DR. SEIDMAN: 5D and C.

21 DR. BELSITO: 5C.

22 DR. ANDERSEN: D and C show how we would

208

1 maybe like to communicate with you about what

2 details are actually available in these tox of

3 studies. Now, maybe the acute tox aren't the most

4 important studies on earth, but in getting ready

5 for this meeting that's what we had time to play

6 with.

7 And I think that there is a prevailing

8 sentiment that those tables have more information

9 content than any of the verbiage that we can

10 write. At a glance you can see what it is you

11 see.

12 DR. BELSITO: So we would get rid of all

13 the verbiage. These paragraphs would disappear

14 and under Acute Toxicity it would just say --

15 DR. SEIDMAN: I think that's on the

16 table. And it's on the table for different

17 endpoints. You might not want verbiage for acute,

18 but you might want it for subacute or chronic.


20 DR. SEIDMAN: Because I think that's

21 going to be a case-by-case depending on the

22 endpoint.


209

1 SPEAKER: But it's up for discussion.

2 DR. BELSITO: No, I mean, I think

3 certainly for the acute. I mean, we all know what

4 an acute study is. And, you know, basically we're

5 looking at, you know, the --

6 DR. SNYDER: The most important thing

7 for an acute study is the LD50.

8 DR. SEIDMAN: If it's reported. We

9 don't always get an LD50.

10 DR. SNYDER: Right, but that kind of

11 goes to (off mike).

12 DR. ANDERSEN: It's two animals. We're

13 not very interested anymore.

14 DR. SNYDER: But under the Acute section

15 we have basically, at least I can count, four or

16 five different summary statements where we could

17 have just put that all in one saying there was low

18 toxicity based upon LD50s and an oral (off mike)

19 and --

20 DR. ANDERSEN: As shown in tables.

21 DR. SNYDER: Exactly.

22 SPEAKER: Right.

210

1 SPEAKER: (off mike)

2 DR. SEIDMAN: And (off mike) the summary

3 statement and address that in the text.

4 DR. SNYDER: Yeah, up front.

5 DR. SEIDMAN: And then up front in the

6 table.

7 MS. ROBINSON: Like the kojic acid.

8 DR. SNYDER: Yeah, like kojic acid,

9 right up front.

10 MS. ROBINSON: Okay.

11 DR. SNYDER: There's three or four (off

12 mike) around that.

13 DR. BELSITO: Then no verbiage. Just

14 your summary statement, no verbiage, and a

15 referral to the tables.

16 DR. SEIDMAN: That's what I would prefer

17 (off mike).

18 DR. ANDERSEN: Yeah, definitely.

19 SPEAKER: Really shortened this stuff.

20 And that's certainly a case for a lot of the

21 animal tox studies.


211

1 DR. SEIDMAN: Well, there's a third

2 wrinkle on this, if I can just raise the issue,

3 because it came up in the other group (off mike)

4 has to do with editorializing a bit. So like

5 under Azelaic Acid, I put -- this was how I

6 summarized this particular study, given the low

7 toxicity for azelaic acid by the oral and (off

8 mike) routes of exposure and as (off mike) dermal

9 route of exposure in concentration used in

10 cosmetics, because azelaic acid presents a very

11 low risk of causing acute toxicity (off mike).

12 Now, in the -- when Jay brought up the

13 -- he mentioned that he'd prefer no conclusion on

14 the data, but we always are considering dose. So

15 here we -- well, we are considering dose of, you

16 know, use in cosmetics, and that's what we always

17 are comparing our data to in the literature. So

18 we're just editorializing what we put in the

19 beginning and end, you know, summarizing the data

20 and then editorializing.

21 Where does one begin and the other end?

22 MR. ANSELL: I think it was our position

212

1 that when they start drawing conclusions from the

2 data, that deserved to be in the discussion

3 section. They really didn't go to whether the

4 staff should be doing conclusions or not but

5 rather where they should be included, particularly

6 because if we start parsing it too finely we'll

7 end up drawing conclusions about energenicity and

8 outside of the entire scope of evidence that might

9 be relevant to a conclusion of carcinogenicity.

10 So we thought within the data section it

11 was appropriate to have summaries of the data, but

12 that when you went the further step and said so

13 I'm concluding that this presents a low risk, that

14 that should not be in the data section; that

15 should be in the discussion section.

16 DR. LIEBLER: I agree with that.


18 DR. SNYDER: I think we should just

19 stick to summarizing the data, not interpreting

20 the data.

21 DR. BELSITO: Mm-hmm.

22 DR. SEIDMAN: In the individual


213

1 sections.

2 DR. BELSITO: In the individual

3 sections.

4 DR. SEIDMAN: Let's discuss the

5 discussion section then at the end of the

6 document. Do we consider -- in the CIR, is it

7 appropriate to consider, which I think it is,

8 concentration of use relative to the data?

9 DR. BELSITO: We always do.

10 SPEAKER: Absolutely.

11 DR. SEIDMAN: Okay, so that's fair

12 enough.


14 DR. SEIDMAN: Just let me get a feel for

15 that. Okay.

16 DR. ANDERSEN: Yeah. And I think if I

17 can take that one step further. Even at this

18 early stage of the document -- let's say that this

19 is now December and we got this and we had this

20 discussion back in September -- that language that

21 Brenda developed in the front end relating to

22 azelaic acid, I'm not sure I would be

214

1 uncomfortable in preloading the discussion section

2 with that information for your consideration.

3 It's a toxicologist's review of the information.

4 It sure looks that way and then you guys get to

5 look at it.

6 DR. SNYDER: Well, when we make a

7 comment on kojic acid it makes writing the summary

8 very easy because you just basically merge all

9 those summaries (off mike) flow in a summary

10 statement.

11 DR. ANDERSEN: You bet. So I think we

12 have in the past not touched anything relating to

13 the discussion section until we have a couple of

14 panel discussions under our belt. But I'm

15 wondering whether we may not be able to just be

16 able to prime it a little bit. If you disagree,

17 you're not going to be reluctant to say so. If

18 you agree and say attaboy, then you will have

19 accomplished something. But I think, you know,

20 Jay's message -- the reinforcement to the other

21 group that to the extent that we possibly can,

22 those are discussion elements.

215

1 SPEAKER: Message received.

2 DR. BELSITO: On page 11, the Leong

3 Study, I don't think it belongs there, but I don't

4 know really where to place it other than perhaps

5 to eliminate it completely. It says the

6 biocompatibility of bioerodible polyanhydrides and

7 the toxicology of the polymer breakdown products.

8 That certainly doesn't belong under chronic

9 toxicity, I don't think.

10 SPEAKER: We'd be comfortable removing

11 it.

12 DR. BELSITO: Yeah. I don't think it

13 adds anything to the document at all.

14 DR. SNYDER: I agree. There's lots of

15 stuff related to designating time versus

16 short-term studies in that section. And also on

17 that same page right above it, that looks like

18 aminotricity acids (off mike) that should go back

19 to the genotox section.

20 MS. ROBINSON: I'm sorry. Which page?

21 DR. SNYDER: On page 11. The (off mike)

22 toxicity and mutagenicity of the degradation

216

1 products were driven by a forward mutation (off

2 mike). That's not in the right place.

3 That's got to go.

4 MS. ROBINSON: That's part of the Leong

5 Study.

6 DR. BELSITO: That's part of what we're

7 deleting. We're deleting that whole thing.

8 Leong. We're deleting the whole bottom two-thirds

9 of page 11.

10 DR. SNYDER: Okay. Right.

11 DR. BELSITO: And the top part of page

12 12. And Table 6, it says summary of mammalian

13 effects.

14 And then under Genotoxicity it has

15 negative aims, so that's not mammalian. So do we

16 want to get rid of mammalian and just say summary

17 of effects?

18 DR. ANDERSEN: Very advanced salmonella.

19 (Laughter)

20 DR. BELSITO: Point well taken. Page

21 20, that's just typos.



217

1 DR. BELSITO: On page 26, the third

2 paragraph up from the bottom, it says basic acid

3 did not show any teratogenic effect on fetal

4 toxicity. Is that redundant, did not show any

5 fetal toxicity?

6 DR. LIEBLER: So just remove any

7 teratogenic effect.

8 DR. BELSITO: Right. Just any fetal

9 toxicity. Did not show fetal toxicity.

10 DR. ANDERSEN: You know, I think

11 actually, Curt, checking on this I'm not sure what

12 the truth is, but those are two separate

13 endpoints. I mean, I could have either yes or no

14 for fetal toxicity and still have some increased

15 incidence in birth defects, so.

16 DR. BELSITO: So did not show

17 teratogenicity?

18 SPEAKER: (off mike) in developmental

19 studies that separate out the two.

20 DR. ANDERSEN: So what should be done

21 there is take out the word "teratogenic effects

22 in."

218

1 DR. BELSITO: Right. It just did not

2 show fetal toxicity, teratogenicity, and neonatal

3 toxicity in rabbit studies.

4 SPEAKER: Right.

5 DR. ANDERSEN: (off mike) did not cause

6 fetal toxicity (off mike).

7 SPEAKER: Yeah, "did not cause" would be

8 better to show --

9 DR. BELSITO: And "separate?"

10 SPEAKER: Yes.

11 DR. ANDERSEN: And that should be "or"

12 instead of "and."

13 DR. BELSITO: A question that I had

14 throughout this report is that we've already

15 looked at some other aliphatic diesters, for

16 instance, maleic acid. And did we want to bring

17 in at least a summary of any of that data into

18 this report to help us out in terms of the safety

19 assessment or --

20 DR. ANDERSEN: I forget. What's the

21 (off mike)?

22 DR. LIEBLER: Maleic acid is two carbons

219

1 with two carboxins with a double bond between (off

2 mike) three carbons.

3 DR. ANDERSEN: So it's about as short as

4 you can get.

5 DR. LIEBLER: Yeah.

6 DR. ANDERSEN: And these are a bit

7 longer. It's got eight carbons including the two.

8 I'm not sure --

9 DR. LIEBLER: You've got adipic acid

10 (off mike) I don't know if that's used.

11 DR. ANDERSEN: -- how instructive it is.

12 DR. BELSITO: Okay. So I'll strike that

13 question. Okay. And I guess the only new data we

14 got were 2 additional sensitization studies at 1.2

15 percent. Is that -- I'm trying to look at what we

16 sent as new. That's the only thing I picked up.

17 It was sent by e-mail or some fashion,

18 some additional studies, and I just made a note

19 that there were -- in addition to what we have

20 here in the document, there were two additional

21 sensitization studies done at 1.2 percent, which

22 doesn't really help us since it's used at a higher

220

1 concentration.

2 SPEAKER: (off mike) I thought it was a

3 2.2 negative (off mike).

4 DR. BELSITO: It may be already in the

5 document. I didn't see it.

6 DR. ANDERSEN: No, the new thing that

7 was sent out was September 18th. I had it dated

8 when the council provided it. It isn't in the

9 book.

10 DR. BELSITO: Right. Okay.

11 DR. SNYDER: August 18th and September

12 24th. There's a memo from John Bailey on August

13 18th that we got prior to coming to the meeting.

14 For this meeting we got one on 9-16 to 9-18.

15 DR. BELSITO: Yeah. And then we got

16 another one September 16th that I guess was handed

17 out today. Is that right?

18 MS. ROBINSON: Yes.

19 DR. BELSITO: And 18th. So the 16th is

20 7.8 percent --

21 SPEAKER: Two.

22 DR. BELSITO: 7.2 (off mike). And then


221

1 it was a human repeat in self patch testing.

2 SPEAKER: Yes.

3 DR. BELSITO: Fifty-one subjects

4 completed. And then --

5 SPEAKER: And they all take (off mike).

6 DR. BELSITO: Another study, Primary

7 Skin Irritation, and this is 100 percent diethyl

8 and 30 percent diethyl, and 8 male Japanese White

9 Strain rabbits. At that high concentration there

10 were some allergic reactions.

11 SPEAKER: (off mike) 100 percent.

12 DR. BELSITO: A hundred percent, yeah.

13 And then case reports. What is (off mike)? Oh,

14 (off mike) motion, okay.

15 DR. ANDERSEN: That chart is also

16 something we put together that basically

17 summarizes what's in the report. Again, it takes

18 a long time to read through the case literature.

19 Again, we're wondering whether a table that shows

20 it -- in this case shows that there were some

21 positive reactions in the case literature. You

22 can do what you will with it, but it's -- at a

222

1 glance you can see that there are positive

2 reactions. You don't have to dig for it.

3 DR. BELSITO: Yeah. Well --

4 DR. SEIDMAN: I'm going to pass out this

5 table. (off mike) I don't think you're going to

6 find it of value, but I'm going to pass it out.

7 This is case reports.

8 DR. LIEBLER: I think they've got them.

9 DR. BELSITO: We've got them, yeah.

10 DR. SEIDMAN: Okay, I'm sorry. It's

11 really not -- it's not for induction --


13 DR. SEIDMAN: -- so I think this has a

14 policy and the (off mike) do not.

15 DR. BELSITO: Well, looking at what we

16 have for these and the new data that we got, we

17 don't have impurities.

18 We don't have UV absorption. But

19 looking at the structure, there are no rings.

20 They're not likely to absorb. We have a negative

21 Ames but no mammalian genotoxicity. And then do

22 we have sufficient carcinogenicity? No.

223

1 If we have sufficient carcinogenicity

2 and you don't feel we need mammalian genotoxicity

3 and we have negative repro tox, then do we really

4 need impurities? Because presumably whatever

5 impurities were there were tested and weren't

6 giving problems, so.

7 DR. SNYDER: We only really have one

8 carcinogenicity study.


10 DR. SNYDER: The other one is actually

11 renal processing (off mike).

12 DR. LIEBLER: Is the one you're talking

13 about called the BIBRA 96 reference?

14 DR. SNYDER: Yes.

15 DR. LIEBLER: Which has very little

16 information provided, right?

17 DR. SNYDER: 10 milligrams per kilogram

18 for (off mike).

19 DR. LIEBLER: And the only other one is

20 around liver phocyte tests.

21 SPEAKER: In the (off mike) in the test

22 plan, someplace in here a whole bunch of data on

224

1 genotoxicity.


3 SPEAKER: All we have so far are (off

4 mike), but the American Chemistry Council has

5 provided us with data before. So if you wanted

6 these expanded, it's page 15 in the (off mike) HPB

7 test plan that was provided by the council in one

8 of their submissions. It's kind of like that

9 page, a quarter of an inch.

10 SPEAKER: (off mike) looks like a lot

11 that they have. There was a 13-week -- or the 90

12 days thing.

13 SPEAKER: Well, those should probably be

14 summarized.

15 SPEAKER: Yeah. Yeah, we need to bring

16 those in.


18 SPEAKER: Yeah, I think the question the

19 other group had related to is this enough or do

20 you want to see the real studies? They were

21 inclined to see the real studies, but I'll leave

22 it up to you as to what your comfort level is.


225

1 DR. BELSITO: Well, I think we'd

2 probably want to see the real studies, but the

3 question is I'm assuming since this is being put

4 together for HPV and REACH, that these are

5 accurate summaries or statements of what was

6 found. And assuming that's the case, is this safe

7 as used? And do we have enough information?

8 Assuming that, in fact, when we get the real

9 studies they confirm the summary.

10 DR. SEIDMAN: Are you proposing that we

11 get the real studies?

12 DR. BELSITO: I think it's always been,

13 I mean, you know, they're not studies that are my

14 area of expertise.

15 So, you know, from my standpoint, I

16 would read them, but I'd be relying on my

17 colleagues to guide me. I think it's always been

18 the policy of the panel, particularly maybe in

19 this case where we don't have impurities and we're

20 going to be assuming that these are -- we don't

21 need the impurities because whatever the

22 impurities are, they were studied. We'd want to

226

1 see in more detail exactly what was done in the

2 studies. I'm assuming, but let me let Curt, Paul,

3 and Dan discuss that.

4 DR. SNYDER: It's always a case-by-case

5 basis. So if we have 10 chronic studies, even

6 with low numbers of animals, you get a lot more

7 confidence than if you have one study. So if you

8 only have one study, you'd like to have pretty

9 good information to make sure the methodology and

10 the valuations and things like that were

11 appropriate. So I think on a case-by-case basis

12 it's when there is minimal data, I want to see

13 more. When there's minimal data I want to see

14 more data. And when there's lots of data, I don't

15 need to see lots of data, so to speak, of how it's

16 done.

17 DR. SEIDMAN: And so lots of data --

18 lots of data coming from one source, is that

19 right? I haven't reviewed this document.

20 MR. ANSELL: No, no, it's a consortium

21 of producers that come together.

22 DR. SEIDMAN: It's a summary from that

227

1 consortium and there are no original data which

2 were published or which were available to CIR?

3 MR. ANSELL: You'd have to look at the

4 data area because they tried to minimize animal

5 testing, so they uses confrontational methods,

6 they used all sorts of things. But I think if you

7 were to identify what particular effect you're

8 concerned about, we can see if we could get

9 additional data.

10 The package itself goes into, you know,

11 an entire analysis of toxicity and carcinogenicity

12 and chronic toxicity. So, I think getting the

13 full package would be --

14 DR. BELSITO: I don't think we need the

15 full package. In my assessment, what we're

16 lacking right now are impurities and

17 genotoxicity/carcinogenicity. And therefore, we

18 would be relying on, you know, if we don't get

19 impurities that's fine because we, you know, again

20 we can say in the discussion, you know, whatever

21 the impurities are they didn't result to any

22 reproductive or teratogenic effects and they

228

1 didn't result in mutagenic or genotoxic effects or

2 carcinogenic effects if we have that data. So

3 that the data that we're missing right now are the

4 mammalian, genotoxin, carcinogenicity. And then

5 the question becomes are these summaries adequate

6 for my colleagues or do my colleagues want to see

7 the actual studies. And I leave that up to them

8 to comment.

9 MR. RE: Just to note the actual study

10 reports that went to ZIAM and OECD programs (off

11 mike) letting your (off mike). I'm not certain

12 that we could obtain them (off mike).

13 DR. KLAASSEN: Apparently there's not a

14 whole lot of carcinogenicity studies that have

15 been done according to their document either. So,

16 I guess it would be nice to know is that one the

17 only one that's been done? And that one that has

18 been done should have more data. Definitely look

19 at that data. Did they use two mice?

20 MR. ANSELL: You know, if you look in

21 the report, you know, page 14, 15, the results

22 from (off mike) genotoxicity material, mammalian,


229

1 in vitro chromosome, in vivo chromosome, so I

2 think the question is highly relevant.

3 And let us see what data responsive to

4 that question we can get. But it's unlikely to be

5 the entire package (off mike).

6 DR. LIEBLER: We may not need the whole

7 package. In fact, the compound space -- chemical

8 space that this is describing is larger than what

9 we're considering in these ingredients any way.

10 There are a lot of shorter chain things here.

11 There's some unsaturated things that might have

12 different properties.

13 I just feel it sounds like there are

14 data out there that we're not getting. I don't

15 think it's appropriate for us to just decide that

16 we shouldn't look at any of it. So, I think we

17 need to see if we can get some of this. It sounds

18 like from looking at this Table 3, at the end of

19 the HPV report, I don't see any references for

20 anything. This looks like it's stuff that's been

21 done and not published.

22 MR. ANSELL: Yeah, I mean, those are all

230

1 important questions.

2 DR. LIEBLER: And if that's, you know --

3 SPEAKER: And at this stage in the

4 review, (off mike).

5 DR. LIEBLER: It may be, you know, many

6 yards of data or whatever you said, but, on the

7 other hand, it may be something that we can get

8 our hands on and look at and we should at least

9 try to do that.

10 DR. SNYDER: And when there's a NOEL or

11 a NOAEL, it's always nice to know what it was

12 based on rather than just -- because these all

13 just say there was a NOAEL, but they don't say

14 what was the basis. Was it decreased weight gain

15 or was it some, you know, toxicity endpoint that

16 might pop up that we can look at someplace else.

17 So, again, we just need a little bit more

18 information than what's in this summary.

19 DR. BELSITO: So, where are we going?

20 Are we saying insufficient for impurities,

21 genotox, carcinogenicity?

22 Are we tabling to get more information

231

1 from the summary reports that we see here in the

2 diester HPV test plan? Where do we want to go?

3 This is the first time we're seeing this document.

4 DR. SNYDER: I prefer tabling it and

5 asking for the additional data that we know

6 exists. We're going to get it.


8 DR. SNYDER: I think that's a more

9 logical (off mike).

10 DR. BELSITO: So we're going to table it

11 and ask for additional genotoxin carcinogenicity

12 data that appears to be from the diester HPV test

13 plan available to us. And if it's linear feet or

14 data, send it electronically and let us shift

15 through it.

16 MS. ROBINSON: Do we need impurities?

17 No? Impurities?

18 DR. BELSITO: I mean, if they have

19 impurities, that would be great, but, again, I

20 think we can handle -- I mean, we handle

21 reproductive toxicity. You know, we can handle

22 impurities by saying we didn't have impurities,

232

1 but whatever impurities were there didn't result

2 in problems in the genotox, carcinogenicity, and

3 reproductive studies. We've done that before.

4 SPEAKER: That's a wonderfully empirical

5 approach --


7 SPEAKER: -- resolving (off mike).

8 DR. BRESLAWEC: May I ask your opinion

9 on one format matter here? If you look at page 21

10 and 22 and 23 and the top of section 24, it

11 summarizes what are called "skin treatments."

12 These are essentially efficacy studies involving

13 one or more of these components. In the past

14 we've summarized them. An alternate way of

15 dealing with these studies is presented in italics

16 in the middle of page 24 and we'd like your

17 opinion on that.

18 DR. ANDERSEN: It takes much less space.

19 (Laughter)

20 DR. BELSITO: I think when you're

21 dealing with something like azelaic acid that also

22 has a drug use, you know, you're, I think,


233

1 summarizing it as you did in the alternate skin

2 study section -- is fine. I don't think we need

3 all of the details as to whether they wanted to

4 treat acne with minocycline plus azelaic acid and

5 whether there was a difference in those two

6 treatment groups. I mean, that's not --

7 DR. BRESLAWEC: We have the same issue

8 in things like botanicals where there are

9 thousands of studies done on a variety of

10 conditions from growing hair to losing hair. And

11 we prefer not to deal with the effectiveness

12 question.

13 DR. BELSITO: Yeah. Right.

14 DR. BRESLAWEC: Great. Thanks.

15 MR. RE: Just getting back to the

16 availability for a moment, would the CIR entertain

17 the idea of joining the aliphatic esters panel?

18 Because that is the usual mechanism on which you

19 gain access to this data (off mike). So if you'd

20 like to go that way, that would be the traditional

21 way of gaining access to these data (off mike) --

22 SPEAKER: Never done it.

234

1 MR. RE: -- (off mike) part of the (off

2 mike).

3 MR. ANSELL: You know, that's all true.

4 Let us look first and then we will come back and

5 say if there's a problem or not. You know, I

6 expect that there are robust summaries available

7 (off mike). Let us look first.

8 SPEAKER: You know, we pay for ASTM

9 standards, IOC standards (off mike), so we'll need

10 to do that.

11 DR. BELSITO: Okay. So --

12 DR. SNYDER: I have one more question.

13 On page 25, there's a chronic toxicity study in 40

14 rats and 40 rabbits. Do you see it there?

15 MS. ROBINSON: Oh, yeah.

16 DR. SNYDER: They present the results of

17 the rabbits, but there are no rats. Is it in the

18 table there?

19 SPEAKER: (off mike)? I'm sorry.

20 DR. SNYDER: The chronic toxicity was

21 investigated in 40 rats and 40 rabbits. And then

22 we go on to say that chronic toxicity (off mike)

235

1 no significant difference in (off mike) and

2 rabbits, but we don't get any data results for

3 rats.

4 DR. SEIDMAN: Oh.

5 SPEAKERS: Oops.

6 DR. SEIDMAN: Yeah, oops.

7 DR. SNYDER: I didn't look in the table,

8 (off mike) to the table then.

9 DR. SEIDMAN: The two tables I prepared

10 (off mike).

11 DR. BELSITO: Okay. That's what I

12 thought. Okay.

13 DR. SEIDMAN: So I didn't touch this.


15 DR. SEIDMAN: But that's kind of why I

16 think we do need tables because sometimes the

17 reviewers have a lot to do and they might not get

18 all the information. If we have a table, then

19 we're sure to get it.

20 DR. KLAASSEN: That needs to say Table 3

21 right there if it's going to be in Table 3, so you

22 don't have to guess.

236

1 DR. SEIDMAN: If we put it in a table,

2 we'd have to say, of course, reference the table.

3 DR. KLAASSEN: Yeah, right.

4 DR. BELSITO: Any other comments? Okay.

5 Why don't we take a 10-minute break before we move

6 to PEGs, get some coffee, relieve our bladders.

7 (Recess)

�


TEAM�MEETING�MINUTES�ON�SEBACATES�–�DR.�MARKS’S�TEAM�

�

14 DR. MARKS: It will be quick, Alan. Is

15 everybody fine with that, Ron, Ron and Tom?

16 Table. Next we're to the sebacates or sebacates?

17 Which is it?

18 DR. ANDERSEN: Is there a linguist in

19 the house?

20 DR. BERGFELD: It's in the Green Book.

21 DR. MARKS: This is the first time that

22 the panel has seen this report, and obviously with

127

1 that, one of the things is do we want to group all

2 these ingredients together, should we delete some

3 of them, and then obviously move on to data needs?

4 And Ron Hill and Ron Shank also, how do you like

5 Acute Toxicity Tables 5-B, 5-C? Was that helpful?

6 We'll open it up for discussion.

7 DR. SHANK: I guess I'll start. I would

8 go as insufficient data. We need genotoxicity

9 data for microbial and mammalian. However, Table

10 3 from the American Chemistry Council report

11 indicates that there may be some data, but it's

12 not in our report other than the table. Maybe

13 it's already there. My second comment is that

14 there are five other dicarboxyl acids listed in

15 the dictionary. Why are they not included? And

16 the rest are just editorial. You did ask about

17 Tables 5-A, 5-B and 5-C. There's nothing much in

18 those tables, so I would just convert that

19 information to text and delete the tables.

20 DR. MARKS: Ron, did you feel the

21 impurities were okay in that section? Did we have

22 any needs in the impurities?

128

1 DR. SHANK: I don't have that marked.

2 DR. MARKS: There are no impurities, so

3 I guess would that be a need we have to move as

4 insufficient?

5 DR. BERGFELD: Ron?

6 DR. MARKS: Ron?

7 DR. SHANK: I don't have any concerns,

8 but maybe others do.

9 DR. SLAGA: I don't have any concerns

10 here, but mutagenicity in the new data in the back

11 there is some mammalian genotoxicity, so there is

12 genotoxicity, both bacterial as well as mammalian.

13 DR. SHANK: But it's not in the report,

14 so do we actually have the studies or is this just

15 a quotation from some report?

16 DR. HILL: Which specific compounds are

17 in that report?

18 DR. MARKS: We'll want to go over that

19 and make sure because Ron Shank raised the issue

20 of should there be five more ingredients listed

21 and are the ingredients that are already in the

22 report ones that we want to include. Why don't we


129

1 do that and we'll go over it? So far we have the

2 needs, although the table indicates mutagenicity

3 data and genotox data, that doesn't appear in the

4 report itself. Shall we assume that that's going

5 to appear in the report and not put that out as an

6 insufficient at this point?

7 DR. SLAGA: It's in the data in the

8 back.

9 DR. MARKS: So it's in the data in the

10 back.

11 DR. ANDERSEN: I'm not finding it.

12 DR. BERGFELD: It's in the additions

13 behind everything there.

14 DR. SHANK: That is a page 15, diesters.

15 There's the high production volume. There is a

16 report called "Diesters: High Production Volume

17 Test Plan" in the back of the book and on pages 14

18 and 15. It gives mutagenicity data which

19 apparently the American Chemistry Council has

20 those data. So if those data are there, can they

21 be made available to us?

22 DR. ANDERSEN: I got you now. So

130

1 there's a whole series of studies that are

2 described on pages 14 and 15, the details of

3 which, were they captured and put in the document

4 could resolve the concerns.

5 DR. MARKS: Rachel?

6 MS. WEINTRAUB: In terms of a lack of

7 data, I just wanted to make sure that we consider

8 that there's no phototoxocity data and no

9 subchronic toxicity data. So the question is do

10 you think we need that kind of data? Another

11 comment that I had is that on page 24 under the

12 Alternate Skin Study section, there are a few

13 studies mentioned, but then it says, "The safety

14 information from the studies was not provided, or

15 provided in a manner that was not conducive to

16 evaluation." Why include it if it provides

17 absolutely no information? Page 24.

18 MS. ROBINSON: The Alternate Skin

19 Studies?

20 MS. WEINTRAUB: Yes.

21 MS. ROBINSON: With these studies there

22 were limited details, so we just included it


131

1 anyway. But if the panel decides that it's

2 irrelevant, then we'll take it out, but there were

3 very limited details described by the authors.

4 MS. WEINTRAUB: I was wondering if there

5 was some reason to include it just to make clear

6 that we've seen them but find it inclusive.

7 DR. ANSELL: We support that comment.

8 The study goes to the drug efficacy and doesn't

9 really report on safety.

10 DR. MARKS: Correct. Actually starting

11 with page 21. Is that where you started, Rachel?

12 Eliminate everything from 21 to 24, so Skin

13 Treatments all the way to the Alternative Skin

14 Study section because it all relates to the

15 efficacy of these drugs and acne. Valerie, I'll

16 give you two printouts here, once on Azelex, the

17 package insert which isn't very helpful, but

18 there's a much better one on Finacea.

19 Interestingly, I had the same concerns about

20 phototox data, and they have a number of

21 irritations, sensitization, photosensitization and

22 phototox studies on Finacea which is the 15

132

1 percent azelaic acid preparation, so that I'm

2 going to give these to you. The references are in

3 there even though I think that's helpful data in

4 terms of the safety for this group. The rest of

5 these I had concern about no photo absorption, but

6 then again that would speak to the safety. What's

7 your feeling, Ron?

8 DR. SHANK: I don't think these

9 compounds would absorb in the important areas of

10 UV for skin toxicity.

11 DR. MARKS: Under the Clinical

12 Assessments, the diisopropyl sebacate is fine. I

13 had there were a number of severe case reports of

14 allergic contact dermatitis to diethyl sebacate.

15 What was reassuring was they had a RIPT of this

16 compound with a 1.5 percent concentration of

17 diethyl sebacate, and I would suggest that we put

18 a limit on that particular ingredient to that

19 concentration because of the alerts for these

20 multiple cases of severe allergic contact

21 dermatitis.

22 DR. ANDERSEN: What would a good number


133

1 be?

2 DR. MARKS: The 1.5 percent. That's

3 what was found in the cream which they did an RIPT

4 on, so we have that data that we know at that

5 limit that it was safe in that cream.

6 MS. SEIDMAN: The 1.5 percent?

7 DR. MARKS: Yes.

8 MS. SEIDMAN: If you look at the table

9 that I prepared, I prepared a table on the diethyl

10 sebacate allergic contact case reports. So if you

11 look down there, there is a 1 percent diethyl

12 sebacate -- positive. I think there is something

13 less than that. But just look down that table and

14 see what you think.

15 DR. MARKS: Which page?

16 MS. SEIDMAN: This is separate. It's a

17 handout.

18 DR. MARKS: The handout?

19 MS. SEIDMAN: Yes.

20 DR. MARKS: Thank you.

21 MS. SEIDMAN: You're welcome.

22 DR. SLAGA: So these are case report

134

1 individuals? Is that correct?

2 MS. SEIDMAN: Yes.

3 DR. MARKS: So your conclusion from

4 these? Take me through it. These were mostly

5 medications as I read the case reports, hence some

6 had, yes, very high concentrations which isn't

7 surprising that they would sensitize at those

8 concentrations.

9 MS. SEIDMAN: I think there was a.1.

10 DR. MARKS: Was that for patch testing

11 though? It went down. For actually patch testing

12 they went down as I recollect to.01, but that to

13 me just is a little bit different than what

14 concentration could you feel safe going

15 prospectively and not sensitize individuals, not

16 if they've already become sensitized. So that's

17 why I thought the 1.5 percent cream from the

18 maximization test, and that was probably one of

19 these added at the end.

20 MS. SEIDMAN: You're just talking about

21 induction.

22 DR. MARKS: Yes. That was from the PCPC


135

1 memorandum from John Bailey dated August 18 and

2 you'll see in the fourth study down, KGL 2003, a

3 cream containing 1.5 percent diethyl sebacate in

4 human skin by means of the maximization assay was

5 okay. So that's why I thought that that would be

6 safe in light of having this alert from the case

7 reports.

8 DR. ANSELL: You will also see a report

9 dated September 18 for diethyl.

10 DR. MARKS: What does that add, Jay?

11 DR. ANSELL: Just that it was induced at

12 higher percents than that.

13 DR. MARKS: This was with?

14 DR. ANSELL: Diethyl.

15 DR. MARKS: Diethyl. Then I guess you

16 have the contradiction of which limit level are

17 you going to use.

18 DR. ANSELL: Yes.

19 DR. MARKS: I think I'd like to err to

20 that lower concentration. Are there any other

21 comments? Ron Shank, going back to the original,

22 do you think if we have all this data included in

136

1 the body and not just in the tables that we could

2 move forward without insufficient data conclusion?

3 DR. SHANK: Yes. I assume you have

4 those data, it's just not a quote from a review or

5 something, but if the mutagenicity data are

6 available, then they should be included into the

7 report.

8 DR. ANDERSEN: The American Chemistry

9 Council has provided the data whenever we've asked

10 for it in the past, so I don't anticipate that

11 that's a glitch. In a sense, I'm thinking that

12 tabling this to allow those data to be gathered

13 makes sense. I'm also concerned about the idea

14 that there are four other dicarboxyl acids that we

15 didn't capture, I think potentially do that

16 homework as well if this were tabled.

17 DR. SHANK: The dictionary lists five,

18 phthalic acid, malonic acid, succinic acid,

19 glutaric acid and adipic acid.

20 DR. ANDERSEN: I see what you're saying.

21 DR. SHANK: It's just you take the alkyl

22 group, and we start with butyl dicarbonyl where


137

1 there are four CH2 groups, or I think we start

2 with five. So if you look at the alkyl with four

3 and three, two, one and zero, all of those are

4 listed in the dictionary as pH adjusters and

5 fragrance. So if we're including all of the

6 larger ones, is there a reason that we're not

7 including those smaller ones? And I couldn't find

8 that they had been reviewed before.

9 DR. HILL: Could I respond to that

10 briefly? The major issue in my mind with lumping

11 these compounds as a class, the salts to me were

12 no-brainer additions, but these's a fair amount of

13 read-across data or by analogy data that I think

14 makes the implicit assumptions that the starting

15 point in all of the biological handling of these

16 compounds if they're absorbed is ester hydrolysis,

17 actually twice, and so at least in terms of the

18 ones that were already there and these others that

19 are not added, for example, oxalic acid, there are

20 no carbons between the carbonyls, and maleic acid

21 ones, I don't think that's on your list but that's

22 in the table here, there are just two carbons in

138

1 between. So the ester hydrolysis could go very

2 differently there, and I haven't had a chance to

3 digest it because even in the HPV report there's

4 quite a bit of listed read-across data and I'm not

5 sure how read across that data actually is until I

6 have a matter since to map, and since we just got

7 this a short time ago, I didn't have access to

8 that information because if there's penetration of

9 the diester or even monoesters into dermal layers

10 where there are potentially precancerous cells,

11 then that changes everything in my mind in terms

12 of what you can lump together as a class so that

13 then you need information about the biological

14 handling of that to know.

15 DR. BERGFELD: May I get a point of

16 clarification? Alan, you're urging tabling for

17 all the needs that we're assessing and these are

18 needs for further staff work as I see it. Is that

19 official that we would table or we would just hold

20 this to the next time to clarify those? Do we

21 have to officially table this? I mean, we can.

22 DR. HILL: No, you don't have to


139

1 officially table it.

2 DR. BERGFELD: Can just hold it for that

3 information. I'm not sure there's a difference,

4 but when we table things they've been a little bit

5 more worrisome or waiting for a piece of industry

6 rather than in-house sort of clarifications.

7 DR. HILL: We have our marching orders,

8 so I know what it is we're going to do and I guess

9 from that standpoint it doesn't matter what we

10 call it, just postponing further discussion until

11 these data and the question of the further

12 expansion can be resolved is what we're going to

13 do, whether it's tabled or not. Just in terms of

14 the expansion, simply that there may be a place

15 where the line has to be drawn in terms how far

16 apart the dicarboxylic acids groups are on these,

17 and there may be a reason why these are there and

18 the others are not.

19 DR. ANDERSEN: I think that's the answer

20 to the question, but without getting down and

21 dirty and having all of the staff talk that

22 through, I didn't want to commit to that.

140

1 DR. HILL: Then furthermore, if that is

2 the case and there is significant absorption in

3 the toxicology of the resultant alcoholics that

4 come from the ester hydrolysis in some cases come

5 into play and there's data for some of these

6 compounds that are pretty comfortable for not for

7 all if the class is expanded the way it's given,

8 but then again my digestion of the HPV information

9 is still limited. I haven't had enough time with

10 it.

11 DR. MARKS: So I think if I understand

12 where we're going with this, it is the idea to

13 table it or postpone it or however you want to

14 talk about this first look at these cosmetic

15 ingredients, and I guess are we still going to use

16 sebacic acid as our lead ingredient on this, then

17 as it was put in the memo related dicarboxylic

18 acids and their salts and simple esters? We need

19 a genotox carcinogenicity, the primary references,

20 and get that into the document itself, and then

21 the second big issue is to firm up which

22 ingredients we're really going to include in this


141

1 going to include in this report. Are those the

2 two things? And then Valerie, just capture also

3 in there the concerns I had about the sensitivity

4 and potentially having a maximum with a diethyl

5 sebacate concentration of 2.5 percent.

6 DR. HILL: From my perception, this is a

7 fairly complex class as expanded even without

8 adding the others, and just to make sure that

9 Valerie gets the support she needs to wade her way

10 through all of those complexities.

11 DR. ANDERSEN: In looking at the, if you

12 will, parent compound and focusing on the fact

13 that there was an 8 carbon chain between the two

14 carboxylic acid groups, I think part of the logic

15 was that would give us a certain family depending

16 on whether people are comfortable with the esters

17 that are on the list. It begged the question how

18 different is azelaic acid? It's 7, not that

19 different from 8. We would have included one with

20 9 except that's not a cosmetic ingredient, and

21 then we upped it to 10 on the high side. We can

22 certainly examine the question of can we go a

142

1 little lower and can we go a little bit higher

2 with that trepidation of how distance is going to

3 start to matter depending on what you're doing.

4 DR. HILL: And I would also remind you

5 that the biologic handling of even-chain and

6 odd-chain carboxylic acids and I think also

7 dicarboxylic acids ends up quite differently, and

8 actually there are steps that are different, so

9 that probably also needs to be recognized and

10 accounted for.

11 DR. ANDERSEN: So 7 may be more

12 different from 8.

13 DR. HILL: Than 6 is or 10 is.

14 MS. SEIDMAN: Excuse me, handling in

15 what respect?

16 DR. HILL: If you look at the biological

17 handling of fatty acids, and I think the analogy

18 here of carboxylic acids, even chain and odd chain

19 are handled very differently by biologically and

20 double bonds also have some nuances of handling.

21 MS. SEIDMAN: You're talking about

22 metabolism?


143

1 DR. HILL: I'm talking about

2 chain-shortening metabolism, yes. So there's the

3 parent dicaroxylic acid and then assuming the

4 esters are hydrolyzed which there's a lot of

5 implicit assumption that that is the case, where

6 does that happen and when? Does it happen in skin

7 so that nothing systemic leaves other than

8 dicarboxylic acid in each case? Or we have

9 monoesters? Or we have diesters making it into

10 other tissues? Then if you liberate the alcohols,

11 and that happens immediately and fast wherever the

12 compound is dosed, then the toxicology of the

13 alcohols comes into play depending on how much

14 dermal penetration if it's dermal.

15 DR. MARKS: I think, Valerie, when the

16 nuances start as we decide on what ingredients

17 that we include in this report, we're going to

18 have to catch those nuances that Dr. Hill

19 mentioned. Ron Shank, going back, and one of the

20 questions was Table 5 and Table 5-B and 5-C. I

21 don't think you found them particularly helpful.

22 Could you help clarify that so they could be

144

1 improved in the future?

2 DR. SHANK: There's not enough

3 information in my opinion in those three tables to

4 warrant the space of the tables, so I would just

5 include that information in the text.

6 MS. SEIDMAN: I tried to do a table here

7 just because I personally am frustrated as a

8 toxicologist in going through text because I

9 cannot compare doses, I cannot compare species, I

10 can't get a quick read on the data. So personally

11 I felt it was really useful to put things in

12 tables. This table might not have a lot, so you

13 might say for acute maybe we can just do text.

14 Still, for me I find it useful because I can see

15 the doses readily and the species readily and the

16 numbers of animals used. It's all right there.

17 But think about it maybe more for the longer- term

18 studies if you're not happy with it for acute. I

19 think most toxicologists find it very useful to

20 put things in tables.

21 DR. HILL: I would echo the benefits of

22 tables for me for the same exact reasons you said,


145

1 unless there's just really not much data at all.

2 Even if there are two data lines, still you can

3 compare numbers of animals, doses, route of

4 administration, all those things you mentioned.

5 MS. SEIDMAN: We think alike.

6 DR. MARKS: Ron Shank, what more would

7 you liked to have seen?

8 DR. SHANK: I don't put that much

9 importance on acute toxicity tests when we're

10 talking about cosmetics products. We never have a

11 problem with acute toxicity. So to put that

12 information in a table, yes, it makes it easier to

13 read. It's good to have, but I don't use it in my

14 safety evaluation for a cosmetic product because

15 we never get to acute toxicity problems.

16 MS. SEIDMAN: So the relevance of the

17 acute for cosmetic products is not important.

18 That I can accept. But think about other end

19 points as you go through this. This is just a

20 trial balloon, so for other end points that might

21 be more relevant to cosmetic products.

22 DR. SHANK: Absolutely, yes.

146

1 DR. MARKS: I think the conclusion is

2 that we will recommend tabling this. Actually

3 it's the Belsito team which will report first, but

4 we will recommend tabling it to get the genotox

5 and carcinogenicity data in the text and also to

6 firm up what ingredients are actually going to

7 appear in this report. Are there any other

8 comments?

9 DR. ANDERSEN: I think in terms of some

10 of the lessons for this, I want to make sure it

11 gets captured in terms of the data that had been

12 in the back of the report on all of the clinical

13 testing, the skin treatments. You're reaffirming

14 that those, to the extent that they describe the

15 clinical effectiveness, have no place in a safety

16 assessment and if there were safety data such as

17 may be gleaned from what you've provided, Valerie,

18 those will stand on their own.

19 DR. MARKS: Correct.

20 DR. ANDERSEN: So we can really shorten

21 that section down to almost zero.

22 DR. MARKS: Yes. I have it deleted.


147

1 Correct.

2 DR. ANDERSEN: Thank you. Halyna will

3 be pleased.

4 DR. MARKS: Shall we take a break for

5 lunch? Do you think we'll be able to do kojic

6 acid in 5 minutes?

7 DR. BERGFELD: No.

8 DR. ANDERSEN: The audience is on their

9 own for lunch. The panel will be going downstairs

10 to the lobby, make a left, go past the desk, down

11 to the end to the Carleton Room for lunch.

12 (Recess)

�


REPORT

Draft Final Report

Dicarboxylic Acids and Their Salts as Used in Cosmetics Esters of Dicarboxylic Acids as Used in Cosmetics

November 18, 2010 The 2010 Cosmetic Ingredient Review Expert Panel members are: Chairman, Wilma F. Bergfeld, M.D., F.A.C.P.; Donald V. Belsito, M.D.; Curtis D. Klaassen, Ph.D.; Daniel C. Liebler, Ph.D.; Ronald A Hill, Ph.D. James G. Marks, Jr., M.D.; Ronald C. Shank, Ph.D.; Thomas J. Slaga, Ph.D.; and Paul W. Snyder, D.V.M., Ph.D. The CIR Director is F. Alan Andersen, Ph.D. This report was prepared by Monice Fiume., Senior Scientific Analyst/Writer; Bart Heldreth, Ph.D., Chemist.

© Cosmetic Ingredient Review 1101 17th Street, NW, Suite 412 " Washington, DC 20036-4702 " ph 202.331.0651 " fax 202.331.0088 "

[email protected]


ii

TABLE OF CONTENTS Abstract ....................................................................................................................................................................................................................................... 1

Introduction ................................................................................................................................................................................................................................. 1

Chemistry .................................................................................................................................................................................................................................... 2

Definition, Structure and Manufacture ................................................................................................................................................................................. 2

Physical and Chemical Properties ......................................................................................................................................................................................... 3

Analytical Methods ............................................................................................................................................................................................................... 4

Impurities .............................................................................................................................................................................................................................. 4

Ultraviolet Absorption .......................................................................................................................................................................................................... 5

Use .............................................................................................................................................................................................................................................. 5

Cosmetic ............................................................................................................................................................................................................................... 5

Non-Cosmetic ....................................................................................................................................................................................................................... 6

DICARBOXYLIC ACIDS AND THEIR SALTS ........................................................................................................................................................................ 7

General Biology .......................................................................................................................................................................................................................... 7

Absorption, Distribution, Metabolism, and Excretion .......................................................................................................................................................... 7

Percutaneous Absorption .................................................................................................................................................................................................... 11

Peroxisome Proliferation ..................................................................................................................................................................................................... 12

Cellular Effects ................................................................................................................................................................................................................... 12

Animal Toxicology ................................................................................................................................................................................................................... 13

Acute Toxicity .................................................................................................................................................................................................................... 13

Short-Term Oral Toxicity .................................................................................................................................................................................................... 13

Short-Term Inhalation Toxicity ........................................................................................................................................................................................... 14

Subchronic Oral Toxicity .................................................................................................................................................................................................... 14

Subchronic Inhalation Toxicity ........................................................................................................................................................................................... 15

Chronic Oral Toxicity ......................................................................................................................................................................................................... 15

Ocular Irritation .................................................................................................................................................................................................................. 16

Dermal Irritation/Sensitization ............................................................................................................................................................................................ 16

Mucosal Irritation................................................................................................................................................................................................................ 18

Reproductive and Developmental Toxicity ............................................................................................................................................................................... 18

Genotoxicity .............................................................................................................................................................................................................................. 20

In Vitro ................................................................................................................................................................................................................................ 20

In Vivo ................................................................................................................................................................................................................................ 21

Carcinogenicity ......................................................................................................................................................................................................................... 22

Tumor Promotion ................................................................................................................................................................................................................ 22

Clinical Assessment of Safety ................................................................................................................................................................................................... 23

Dermal Irritation ................................................................................................................................................................................................................. 23

Case Reports ....................................................................................................................................................................................................................... 23

ESTERS OF DICARBOXYLIC ACIDS ................................................................................................................................................................................... 24

General Biology ........................................................................................................................................................................................................................ 24

Absorption, Distribution, Metabolism, and Excretion ........................................................................................................................................................ 24

Peroxisome Proliferation ..................................................................................................................................................................................................... 28

DNA Binding/DNA Synthesis ............................................................................................................................................................................................ 29

Hepatic Lipid Metabolism .................................................................................................................................................................................................. 29

Cellular Effects ................................................................................................................................................................................................................... 30

Animal Toxicology ................................................................................................................................................................................................................... 30

Acute Toxicity .................................................................................................................................................................................................................... 30

Short-Term Oral Toxicity .................................................................................................................................................................................................... 30

Short-Term Dermal Toxicity ............................................................................................................................................................................................... 31

Short-Term Inhalation Toxicity ........................................................................................................................................................................................... 32

Subchronic Oral Toxicity .................................................................................................................................................................................................... 32

Subchronic Dermal Toxicity ............................................................................................................................................................................................... 33

Subchronic Inhalation Toxicity ........................................................................................................................................................................................... 33

Chronic Oral Toxicity ......................................................................................................................................................................................................... 33


Dermal Irritation ................................................................................................................................................................................................................. 35

Dermal Sensitization ........................................................................................................................................................................................................... 37

Phototoxicity ....................................................................................................................................................................................................................... 37

Mucous Membrane Irritation .............................................................................................................................................................................................. 37

Reproductive and Developmental Toxicity ............................................................................................................................................................................... 37

Endocrine Disruption .......................................................................................................................................................................................................... 43

Genotoxicity .............................................................................................................................................................................................................................. 43

Carcinogenicity ......................................................................................................................................................................................................................... 45

Tumor Promotion ................................................................................................................................................................................................................ 46

Clinical Assessment of Safety ................................................................................................................................................................................................... 46

Human Exposure ................................................................................................................................................................................................................. 46

Dermal Irritation and Sensitization ..................................................................................................................................................................................... 46

Phototoxicity and Photosensitization .................................................................................................................................................................................. 48


Comedogenicity .................................................................................................................................................................................................................. 49

Case Reports ....................................................................................................................................................................................................................... 49

Risk Assessment ................................................................................................................................................................................................................. 49

Summary ................................................................................................................................................................................................................................... 49

Discussion ................................................................................................................................................................................................................................. 55


iii

Conclusion ................................................................................................................................................................................................................................ 57

Figures ...................................................................................................................................................................................................................................... 58

Figure 1a. Map of the malonic and succinic ester ingredients in this assessment, and associated esterase metabolites .................................................... 58

Figure 1b. Map of the glutaric and straight-chain adipic ester ingredients in this assessment, and associated esterase metabolites ................................. 59

Figure 1c. Map of the branched chain adipic ester ingredients in this assessment, and associated esterase metabolites ................................................... 60

Figure 1d. Map of the sebacic and dodecanedioic ester ingredients in this assessment, and associated esterase metabolites ........................................... 61

Figure 2. Sebacic acid synthesis from castor oil. ............................................................................................................................................................... 62

Figure 3. Diethylhexyl adipate synthesis from adipic acid. ................................................................................................................................................ 62

Charts ........................................................................................................................................................................................................................................ 63

Chart 1. Dicarboxylic Acids; Log Kow vs Molecular Weight ........................................................................................................................................... 63

Chart 2. Dicarboxylic Acids and their Salts; Log Kow vs Molecular Weight ................................................................................................................... 64

Chart 3. Example of the effects of chain length and branching on solubility. Log Kow vs Molecular Weight ................................................................. 65

Tables ........................................................................................................................................................................................................................................ 66

Table 1. Definitions, functions and structures of dicarboxylic acid, salt and ester ingredients in this safety assessment ................................................ 66

Table 2a. Physical and Chemical properties of the alkyl dicarboxylic acid and salt ingredients. ...................................................................................... 71

Table 2b. Physical and Chemical properties of the mono- and di-carboxylic acid esters. ................................................................................................. 72

Table 3a. Frequency and concentration of use by duration and exposure - Dicarboxylic Acids and Their Salts .............................................................. 75

Table 3b. Frequency and concentration of use by duration and exposure - Esters of Dicarboxylic Acids ........................................................................ 76

Table 3c. Current and historical frequency and concentration of use according to duration and type of exposure - previously reviewed esters ............. 78

Table 3d. Ingredients not reported to be used ................................................................................................................................................................... 79

Table 4. Acute toxicity - Dicarboxylic Acids and Their Salts ............................................................................................................................................ 80

Table 5. Ocular Irritation - Dicarboxylic Acid and Their Esters ........................................................................................................................................ 82

Table 6. Dermal irritation and sensitization - Dicarboxylic Acids and Their Salts ............................................................................................................ 83

Table 7. Genotoxicity studies - Dicarboxylic acids and Their Salts ................................................................................................................................... 84

Table 8. Induction of peroxisome proliferation – Esters of Dicarboxylic Acids ................................................................................................................ 86

Table 10. Ocular Irritation - Esters of Dicarboxylic Acids ................................................................................................................................................. 90

Table 11. Dermal irritation and sensitization - Esters of Dicarboxylic Acids .................................................................................................................... 91

Table 12. Genotoxicity studies - Esters of Dicarboxylic Acids ......................................................................................................................................... 93

Table 13. Clinical dermal irritation and sensitization - Esters of Dicarboxylic Acids ....................................................................................................... 97

Table 14. Case reports - Esters of Dicarboxylic Acids ..................................................................................................................................................... 100

References ............................................................................................................................................................................................................................... 101

Appendix I – Estease Metabolite Summary Data .................................................................................................................................................................... 113


1

ABSTRACT

The CIR Expert Panel assessed the safety of dicarboxylic acids, their salts and esters as used in cosmetics. Most of these dicarboxylic acids function in cosmetics as pH adjusters and fragrance ingredients. The functions of most of the salts are not reported, but sodium succinate functions as a buffering agent and pH adjuster. Some functions of esters include skin conditioning, fragrance ingredients, plasticizers, solvents, and emollients. The Panel reviewed the relevant animal and clinical data related to dicarboxylic acids and their salts and esters and concluded that the dicarboxylic acids, and the salts and the esters of dicarboxylic acids, named in this report are safe in the present practices of use and concentration. Were ingredients in these groups not in current use to be used in the future, the expectation is that they would be used in product categories and at concentrations comparable to others in these groups.

INTRODUCTION

This safety assessment includes sebacic acid and other alkyl α,ω-dicarboxylic acids, salts, monoesters and diesters.

The dicarboxylic acids are terminally functionalized straight alkyl chains characterized by a separation between the acid

functional groups of one to 10 carbons (1 carbon = malonic acid; 2 carbons = succinic acid; 3 carbons = glutaric acid; 4

carbons = adipic acid; 5-6 carbons = no representative cosmetic ingredients; 7 carbons = azelaic acid; 8 carbons = sebacic

acid; 9 carbons = no representative cosmetic ingredients; and 10 carbons = dodecanedioic acid). The simple alkyl di-esters

are the result of the condensation of alkyl dicarboxylic acids and two equivalents of alkyl alcohols. These ingredients can be

metabolized via hydrolysis back to the parent alcohol, the mono-ester, and the parent dicarboxylic acid (Figure 1). The

simple alkyl esters (mono- and di-) of these dicarboxylic acids have straight or branched side chains ranging in length from

one to 18 carbons. Throughout this report, the data are presented by order of acid chain length (i.e., beginning with malonic

acid and ending with dodecanedioic acid; beginning with dimethyl malate and ending with diisocetyl dodecanedioate).

Accordingly, this draft report presents available information pertinent to the safety of 56 cosmetic ingredients in two

groups, first, the 12 alkyl dicarboxylic acids/salts and, second, the 44 corresponding esters (mono- and di-). The alkyl dicar-

boxylic acids and salts include:

malonic acid succinic acid sodium succinate disodium succinate glutaric acid adipic acid

azelaic acid dipotassium azelate disodium azelate sebacic acid disodium sebacate dodecanedioic acid.

The esters include:

diethyl malonate decyl succinate dimethyl succinate diethyl succinate dicapryl succinate dicetearyl succinate diisobutyl succinate diethylhexyl succinate dimethyl glutarate diisobutyl glutarate diisostearyl glutarate dimethyl adipate diethyl adipate dipropyl adipate dibutyl adipate

dihexyl adipate dicapryl adipate di-C12-15 alkyl adipate ditridecyl adipate dicetyl adipate diisopropyl adipate diisobutyl adipate diethylhexyl adipate diisooctyl adipate diisononyl adipate diisodecyl adipate dihexyldecyl adipate diheptylundecyl adipate dioctyldodecyl adipate diisocetyl adipate

diisostearyl adipate isostearyl sebacate diethyl sebacate dibutyl sebacate dicaprylyl/capryl sebacate diisopropyl sebacate diethylhexyl sebacate dibutyloctyl sebacate diisooctyl sebacate dihexyldecyl sebacate dioctyldodecyl sebacate diisostearyl sebacate dioctyldodecyl dodecanedioate diisocetyl dodecanedioate


2

The structures and functions of these ingredients are presented in Table 1.

A safety assessment of diethylhexyl adipate (often inaccurately named dioctyl adipate)1 and diisopropyl adipate was

published in 1984 with the conclusion that these ingredients are safe as used in cosmetics.2 The safety of these ingredients

was reviewed and confirmed in 20053 and 2006.4 Additionally, dibutyl adipate was originally reviewed in 1996, and at that

time the available data were found insufficient to support the safety of dibutyl adipate in cosmetic formulations. When re-

reviewed in 2006, additional data were made available to address the needs identified by the CIR Expert Panel, and an

amended conclusion was issued stating that dibutyl adipate is safe for use in cosmetic formulations.5

The acids and their salts included in this report function in cosmetics as pH-adjusters, and the esters function as

fragrance ingredients, plasticizers, skin-conditioning agents and/or solvents and corrosion inhibitors.

CHEMISTRY

Definition, Structure and Manufacture

The CAS numbers, definitions, structures and functions for the alkyl dicarboxylic acid, salt and ester ingredients

included in this report are given in Table 1.

Alkyl Dicarboxylic Acids

While many of the alkyl dicarboxylic acids are present in natural products, commercial production of these acids has

historically occurred via alkali pyrolysis of lipids.6 For example, when castor oil (a lipid which is comprised of approximately

84% ricinoleic acid-sidechain bearing triglycerides) is pyrolyzed with sodium hydroxide, some of the major products are

sebacic acid and 2-octanol (Figure 2).6 Sodium and potassium salts of the alkyl dicarboxylic acids are readily prepared via

addition to the appropriate stoichiometric equivalent(s) of sodium hydroxide or potassium hydroxide, respectively.

Malonic Acid (C3)

Malonic acid, first prepared by malic acid oxidation, is commonly manufactured by more recent methods including

the ozonolysis of cyclopentadiene or the air oxidation of 1,3-propanediol.7

Succinic Acid (C4)

Succinic acid is an intermediate of the citric acid cycle and is found in almost all plant and animals cells, although at

very low concentrations.8 Succinic acid is commonly produced synthetically by catalytic (e.g., nickel or palladium catalyst)

hydrogenation of maleic anhydride.

Glutaric (C5) and Adipic(C6) Acids

Although glutaric acid is often encountered in nature, adipic acid is not commonly encountered in nature. Glutaric

and adipic acids were first synthesized by oxidation of castor oil with nitric acid. However, adipic acid is now more common-

ly manufactured by oxidation of cyclohexane, cyclohexanol, or cyclohexanone, and glutaric acid may be manufactured by

ozonolysis of cyclopentene.9

Azelaic Acid (C9)

Azelaic acid, first detected in rancid fats, was originally produced via nitric acid oxidation of oleic acid. 10 Azelaic

acid is a naturally-occurring dicarboxylic acid that can be found in dietary sources, such as whole grains.11 Azelaic acid is

commonly manufactured by oxidative cleavage of oleic acid (obtained from grease or tallow) with chromic acid, nitric acid or

by ozonolysis.10,7

Sebacic Acid (C10)

Sebacic acid was originally isolated from distillation products of beef tallow. More recently, however, sebacic acid


3

has been manufactured via alkali pyrolysis of castor oil, as mentioned above and drawn in Figure 2, or by alkali pyrolysis of

ricinoleic acid.12,7

Dodecanedioic Acid (C12)

Dodecanedioic acid can be manufactured by fermentation of long-chain alkanes with a specific strain of Candida

tropicalis.13 Another method of manufacture involves the nitric acid oxidation of a mixture of cyclododecanone and

cyclododecanol.7

Alkyl Dicarboxylic Acid Esters

The alkyl dicarboxylic acids are easily esterified with the appropriate alcohol, with our without acid or metal catalyst

(Fischer esterification).9 For example, diethylhexyl adipate can be manufactured from adipic acid and ethylhexanol with an

acid catalyst (Figure 3).

Diethyl Malonate

Malonic acid esters can be produced either by cobalt-catalyzed alkoxycarbonylation of chloroacetates with carbon

monoxide in the presence of the appropriate alcohol, or by hydrolysis of cyanoacetic acid followed by esterification with the

respective alcohol.14 Diethyl malonate is prepared from chloroacetic acid and sodium cyanide followed by esterification with

ethanol and sulfuric acid.15

Diisopropyl Adipate

Diisopropyl adipate is produced by esterification of adipic acid with an excess of isopropanol. The excess alcohol is removed by vacuum stripping and the ester is then alkali-refined and filtered.

From the Final Report on the Safety Assessment of Dioctyl Adipate and Diisopropyl Adipate2

Dibutyl Adipate

Adipic acid is esterified with butyl alcohol by a continuous distillation process.16

Diethylhexyl Adipate

Diethylhexyl adipate can be prepared by the reaction of adipic acid and 2-ethylhexanol in the presence of an esterifi-

cation catalyst such as sulfuric acid or para-toluenesulfonic acid (Figure 3).17 Purification of the reaction product includes

removal of the catalyst, alkali refining, and stripping.2

Alkyl Succinates

Succinic anhydride reacts readily with alcohols to give monoesters of succinic acid (e.g., decyl succinate from

decanol), which are readily further esterified to the diesters by Fischer methods.7 Dimethyl succinate can be produced from

methanol and succinic anhydride or succinic acid, or by hydrogenation of dimethyl maleate. Diethyl succinate can be

prepared by the same methods (from ethanol or diethyl maleate).

Physical and Chemical Properties

Tables 2a lists physical and chemical properties of the dicarboxylic acids and salts and Table 2b lists the properties

of the esters. Charts 1, 2, and 3 demonstrate the relationship between molecular weight and the log octanol – water partioning

coefficient.

Dicarboxylic Acids - General

The alkyl dicarboxylic acids vary considerably in their physical properties. The shorter chain (malonic, succinic, and

glutaric) members are crystalline solids, very water-soluble, and have limited solubility in organic solvents. As the chain

length increases through adipic to dodecanedioic, water solubility decreases sharply (although still soluble in hot water). In

other words, the water solubility of these acids is inversely proportional to their chain length. There is a marked alternation in


4

melting point with changes in carbon number from even to odd.7 Odd members (e.g., malonic acid and glutaric acid) exhibit

lower melting points and higher solubility than even carbon number alkyl dicarboxylic acids (e.g., succinic acid and adipic

acid). These alternating effects are believed to be the result of the inability of odd carbon number compounds to assume an

in-plane orientation of both carboxyl groups with respect to the hydrocarbon chain.

Dicarboxylic acids react with Brønsted-Lowry bases (e.g., sodium hydroxide) to form carboxylate salts (e.g., sodium

succinate or disodium succinate). Dicarboxylic acids also react with alcohols to give mono- and di-esters, such as those in

this report.

Esters

The diesters, in contrast to the free acids, are much more lipid soluble and more difficult to dissolve in water. The

mono-esters, by definition, are hybrids of the acids and diesters, but their physical properties are much more closely related to

the diesters.

The short-chain alkyl (i.e., methyl, isopropyl, and butyl) mono- and diesters are more soluble in water, less lipo-

philic, and relatively more volatile than the corresponding longer-chain alkyl (i.e., C8-C13 alcohol) esters.18 Most esters with

molecular weights greater than 340 have boiling points greater than 300°C and are relatively non-volatile and lipophilic (log

Kow >7).

Analytical Methods

Succinic Acid

Methods used to analyze succinic acid include acidimetric titration for acidity; comparison with platinum-cobalt (Pt-

Co) standard calibrated solutions for color; oxidation with potassium permanganate for detection of unsaturated compounds;

atomic absorption or plasma spectroscopy for metals; and titration with silver nitrate or barium chloride for chloride or sulfate

detection, respectively.7 Small concentrations of succinic acid can be detected by common instrumentation such as gas/liquid

chromatography and polarography.

Adipic Acid

Adipic acid can be extracted from a water sample and analyzed by gas chromatography/mass spectrometry.17

Sebacic Acid

Gas chromatography can be used to identify sebacic acid in air.19

Diisopropyl Adipate and Diethylhexyl Adipate

Diisopropyl adipate and diethylhexyl adipate can be identified through standard infrared (IR) spectroscopy. Gas-liquid chromatography (GLC), liquid-liquid extraction, mass spectrometry, and high-pressure liquid chromatography (HPLC) are also methods of analysis for the adipates.


Impurities

Diethyl Malonate

Diethyl malonate is a colorless organic liquid with an ester like odor.14 The purity is typically > 99 %. Impurities

from the production process include ethanol (ca. 0.1 % w/w), ethyl acetate (ca. 0.05 % w/w), and ethyl methyl malonate (ca.

0.05 % w/w).

Dibutyl Adipate

Impurities are generally not found due to the manufacturing process, but available data demonstrate that arsenic

levels are below a detection limit of 1 ppm, heavy metals (as lead) are below a detection limit of 10 ppm, and sulfated ash is

below a detection limit of 0.1%.16


5

Diisopropyl Adipate and Diethylhexyl Adipate

Diisopropyl adipate and diethylhexyl adipate are considered stable; however, hydrolysis of the ester groupings may occur in the presence of aqueous acids or bases. No known impurities occur in either diisopropyl adipate or diethylhexyl adipate, although the acid values imply the presence of adipic acid or of the monoester in both.


Diethylhexyl adipate is commercially available with the following specifications: purity – 99 to 99.9%; acidity – 0.25

µg/100g max; moisture – 0.05 to 0.10% max.17

Diisopropyl Sebacate

A supplier reported that the expected impurities in diisopropyl sebacate are the starting material sebacic acid, <0.3%,

and isopropyl alcohol, <0.2%.20

Ultr aviolet Absorption

The ingredients included in this review would not be expected to have any meaningful ultraviolet (UV) absorption.

Except for the acid and ester functional groups, these ingredients do not possess any π-bonds or non-bonding electrons. The

π-bonds and non-bonding electrons in the acid and ester functional groups are not part of any conjugated systems. According-

ly, the likelihood of any of these ingredients to absorb light within the UVA-UVB spectrum, at a detectable molar absorpti-

vity, is extremely low. As such, no UVA-UVB absorption data were found.

USE

Cosmetic

The ingredients included in this safety assessment have a variety of functions in cosmetics.21 The majority of the

dicarboxylic acids function in cosmetics as pH adjusters and fragrance ingredients. The functions of most of the salts are not

reported, but it is stated that sodium succinate functions as a buffering agent and pH adjuster. For the esters, some of the

common functions include skin conditioning agents, fragrance ingredients, plasticizers, solvents, and emollients. The

functions of all ingredients are listed in Table 1.

Six of the 12 dicarboxylic acids and their salts and 24 of the 44 esters included in this safety assessment are reported

to be used in cosmetic formulations. The frequency of use of the acids and salts, as supplied to the Food and Drug Admini-

stration (FDA) by industry as part of the Voluntary Cosmetic Registration Program (VCRP),22 and the concentration of use, as

supplied by industry in response to a Personal Care Products Council (Council) survey, are found in Table 3a. The frequency

and concentration of use of the esters, with the exception of dibutyl, diisopropyl, and diethylhexyl adipate, which have

previously been reviewed, are found in Table 3b. The current and historical use data for the 3 previously reviewed esters are

found in Table 3c. The 6 acids and salts and 20 esters not currently reported to be used are listed in Table 3d.

For the dicarboxylic acids and their salts, disodium succinate has the greatest number of reported uses, with a total of

45. The acid with the highest concentration of use is succinic acid, with a use concentration up to 26%; use at this

concentration is in rinse-off products. The highest leave-on concentration is 0.4% disodium succinate, with dermal contact

exposure.

For the esters, diisopropyl adipate has the greatest number of uses, with 70 reported. The highest concentration of

use is for dimethyl glutarate, 15% in a dermal rinse-off product. The ingredients with the highest leave-on use concentrations,

which are all dermal contact exposures, are diethylhexyl adipate, 14%, diisostearyl adipate, 10%, and diisopropyl sebacate,

10%.

A few of the ingredients are applied around the eye, can possibly be ingested, or involve mucous membrane expo-

sure, and some are used in underarm deodorant. None are reported to be used in baby products.


6

Dicapryl and diethylhexyl succinate, dibutyl, dicapryl, diisopropyl, diisobutyl, and diethylhexyl adipate, diisopropyl,

diethylhexyl, and dioctyldodecyl sebacate, and dioctyldodecyl and diisocetyl dodecanedioate are used in hair sprays, and

effects on the lungs that may be induced by aerosolized products containing this ingredient, are of concern.

The aerosol properties that determine deposition in the respiratory system are particle size and density. The para-

meter most closely associated with deposition is the aerodynamic diameter, da, defined as the diameter of a sphere of unit

density possessing the same terminal settling velocity as the particle in question. In humans, particles with an aerodynamic

diameter of ≤ 10µm are respirable. Particles with a da from 0.1 – 10 µm settle in the upper respiratory tract and particles with

a da < 0.1 µm settle in the lower respiratory tract.23,24

Particle diameters of 60-80 µm and ≥80 µm have been reported for anhydrous hair sprays and pump hairsprays,

respectively.25 In practice, aerosols should have at least 99% of their particle diameters in the 10 – 110 µm range and the

mean particle diameter in a typical aerosol spray has been reported as ~38 µm.26 Therefore, most aerosol particles are

deposited in the nasopharyngeal region and are not respirable.

The dicarboxylic acids and their salts and esters are in the European Union (EU) inventory of cosmetic ingredients.27

Adipic acid is on the EU Dangerous Substances List; it is classified as Xi (irritant) and R36 (irritating to eyes).

Non-Cosmetic

Many of the dicarboxylic acids, their salts, and their esters are used in foods as direct or indirect food additives. The

alkyl dicarboxylic acids are unusually versatile because of their two carboxyl groups.9 This enables many additional types of

useful reactions, particularly the manufacture of polymers (e.g., nylon). The most common uses include functions as plastici-

zers, lubricants and building blocks in the manufacture of polyesters, polyamides and other plastics. The alkyl dicarboxylic

acid salts are used to synthesize cyclic ketones, including commercially used macrocyclic musk compounds.28 The diesters

have widespread use as lubricants, plasticizers, and solvents.29

Malonic Acid

Malonic acid is a useful intermediate in the manufacture of barbiturates.30

Succinic Acid

Succinic acid is listed by the FDA as a food additive that is Generally Recognized as Safe (GRAS).31 Succinic acid

is also utilized in detergents, pigments, toners, cement additives, soldering fluxes and as an intermediate in the synthesis of a

number of pharmaceutical products.7

Adipic Acid

Adipic acid is listed as a GRAS food additive by the FDA.32 Adipic acid has several industrial uses in the produc-

tion of adhesives, plasticizers, gelatinizing agents, hydraulic fluids, lubricants, emollients, polyurethane foams, leather tan-

ning, and urethane.7 However, the bulk of the industrial production of adipic acid is driven by its usefulness in the manufac-

ture of nylon-6,6 (in combination with 1,6-hexanediamine).

Azelaic Acid

FDA has approved azelaic acid for use in treating acne and rosacea. A skin cream containing 20% (w/w) azelaic

acid, is indicated for the topical treatment of mild-to-moderate inflammatory acne vulgaris,33 and a gel containing 15% azelaic

acid is approved for treating rosacea.34 These drugs are available by prescription only. (As a reference point, azelaic acid is

reported to be used at 0.3% in leave-on and 10% in rinse-off formulations that have dermal exposure.35)

Azelaic acid is used in the manufacture of plasticizers, lubricants, and greases. Azelaic acid was identified as a

molecule that accumulated at elevated levels in some parts of plants and was shown to be able to enhance the resistance of


7

plants to infections.36

Sebacic Acid

Sebacic acid was widely used in the U.S. as an aromatic in food before 1973.37

Sebacic acid is used in resorbable polymer systems that deliver chemotherapeutic agents (e.g. cisplatin, carboplatin)

that are implanted at the site of tumors to provide for sustained release of the drugs.38 Sebacic acid and its derivatives have a

variety of industrial uses as plasticizers, lubricants, diffusion pump oils, candles and as intermediates in the synthesis of

polyamides and various alkyd resins.7

Dodecanedioic Acid

Dodecanedioic acid is used in the production of nylon (nylon-6,12), polyamides, coatings, adhesives, greases,

polyesters, dyestuffs, detergents, flame retardants, and fragrances.39

Diethyl Malonate

Diethyl malonate finds great utility as the starting material in Malonic Ester Synthesis, a classic organic chemistry

reaction wherein a very wide variety of esters can be synthesized.28

Diisobutyl Adipate

The FDA has included diisobutyl adipate in Part 181 of Title 21 of the Code of Federal Regulations (CFR) – Prior-

Sanctioned Food Ingredients, Subpart B--Specific Prior-Sanctioned Food Ingredients includes Sec. 181.27, Plasticizers. In

this section, “substances classified as plasticizers, when migrating from food-packaging material shall include...diisobutyl

adipate...” (21 CFR § 181.27).


Diethylhexyl adipate is used as a plasticizer for polyvinyl chloride (PVC) plastics.40

Diethyl Sebacate

Diethyl sebacate was widely used in the U.S. as an aromatic in food before 1973.37

Dibutyl Sebacate

Dibutyl sebacate is a component of PVC.41

DICA RBOXYLIC ACIDS AND THEIR SALTS

GENERAL BIOLOGY

Absorption, Distribution, Metabolism, and Excretion

Dicarboxylic acids are natural metabolic products of the ω-oxidation of monocarboxylic acids when the β-oxidation

of free fatty acids is impaired.42 Under normal physiological conditions, dicarboxylic acids are rapidly β-oxidized, resulting

in very low cellular concentrations and practically non-detectable concentrations in the plasma.43 Medium-chain dicarboxylic

acids (up to 12 carbon atoms) are β-oxidized in mitochondria and peroxisomes. Oxidation of odd- and even-numbered chains

proceeds to different end points. Odd-chain dicarboxylic acids are β-oxidized, giving acetyl Co-A and malonic acid (C3).

Oxidation can then go no further, and malonic acid is the starter of fatty acid synthesis. Even-chain carboxylic acids are com-

pletely oxidized and produce succinyl-CoA, a gluconeogenic substrate, as an intermediate metabolite. Dicarboxylic acids are

more polar than their esters, therefore they will diffuse less readily through normal cell membranes.44

Malonic Acid

Malonic acid can be activated to malonyl-CoA and undergoes decarboxylation to acetyl-CoA by various mammalian

tissues.14


8

Adipic Acid

In rats, after a single oral dose of adipic acid, 70% of the radioactivity was exhaled as carbon dioxide 24 h. Adipic acid and a number of metabolites were recovered in the urine, while very little radioactivity was found in the tissues. After a single oral dose in conjunction with i.p. sodium malonate, the presence of radioactive adipic and succinic acid after 24 h was an indication of β-oxidation. Oral studies have reported recovering 53-67% unchanged adipic acid in the urine of rabbits that were dosed for 2 days, while 59-71% was recovered in the urine following i.v. dosing and 61% was recovered following subcutaneous dosing, with an increase in urinary oxalic acid. In humans, 6.76% of an oral dose of sodium adipate was recovered after 5 days of dosing; in a study in which humans were given adipic acid for 10 days, -61% of the dose was recovered unchanged following oral dosing.

(The studies on adipic acid summarized in this section were performed between 1919 and 1960 and were described

in a summary document.45)

Animal Adipic acid metabolism was studied using fasted male albino rats.45 In one study, in which the rats were given a

single oral dose, by gavage, with 50 mg radioactive adipic acid (labeled on C1 or C2), 70% of the radioactivity was exhaled

as carbon dioxide in 24 h. Adipic acid and the metabolites urea, glutamic acid, lactic acid, β-ketoadipic acid, and citric acid,

were recovered in the urine. Very little radioactivity was found in the tissues. Fasted male rats were also given a single dose

of a solution containing 50 mg radioactive adipic acid (labeled on C1), by gavage, in conjunction with 2 ml of 0.5 M sodium

malonate, given by intraperitoneal (i.p.) injection. After 24 h, both radioactive adipic acid and succinic acid were found in the

urine, which the researchers stated was an indication that adipic acid underwent β-oxidation. In a study in which rats were fed

25 mg radioactive adipic acid (labeled on C1) and 100 mg γ-phenyl-α-aminobutyric acid, followed by a 48-h urine collection,

it was determined that acetate is a metabolite of adipic acid. Finally, rats were given radioactive sodium bicarbonate with

non-radioactive adipic acid. Radioactive citric acid was formed, which suggested that carbon dioxide interacted with a

metabolite of adipic acid. (Details not specified.)

Two rats were dosed orally by gavage with 2.43 g/kg partially neutralized adipic acid for 28 days. In the urine, 67%

of the dose was recovered unchanged. There was no change in excretion pattern over time during the study.

Rabbits were dosed orally by gavage (n=4) or by intravenous (i.v.) administration (n=2) with 2.43 g/kg partially

neutralized adipic acid for 2 days. Following oral administration, 53-61% of the dose was recovered unchanged in the urine.

With i.v. administration, 59-71% was recovered unchanged in the urine. In another study using rabbits, animals were given a

subcutaneous (s.c.) dose of 2000 mg adipic acid; 3 rabbits were given a single dose, one was dosed on days 1 and 5, and one

was dosed on days 1, 5, 9, 13, and 15. On average, 61% of the dose was recovered unchanged in the urine. There was an

increase in urinary oxalic acid concentrations.

A female dog was fed either 150 mg/kg bw adipic acid (in 2 feedings) for 5 days or 750 mg/kg bw (in 2 feedings) for

7 days. In the urine, 18% and 63.6% of the low and high doses were recovered unchanged.

Rabbits (number not stated) were given up to 4 s.c. injections of ≤2000 mg sodium adipate.46 An average of 61% of

the dose was recovered unchanged in the urine. Oxalic acid was increased in the urine.

Human In a study in which one subject was given 33 mg/kg bw sodium adipate, orally, for 5 days (10 g total), 6.76% of the

dose was recovered in the urine. In another study in which one person was given 100 mg/kg bw adipic acid for 10 days (70 g

total), 61% of the dose was recovered in the urine. Administration of 19.0 g adipic acid over 5 days or 23.4 g over 6 or 9

days (1 subject per dose) resulted in 53% of the administered dose recovered in the urine.

C9 to C12 Dicarboxylic Acids

For rats dosed orally with azelaic, sebacic, undecanedioic, and dodecanedioic acid, after 5 days, 2.5, 2.1, 1.8, and 1.6% of


9

the respective acid was found in the urine unchanged. In humans the amount recovered decreased with increasing chain length. After oral dosing, 60, 17, 5, and 0.1% of azelaic, sebacic, undecanedioic, and dodecanedioic acids, respectively, were recovered unchanged in the urine after 12 h. In the plasma of both animals and humans, dicarboxylic acid catabolites that were 2-, 4-, or 6- carbons shorter than the corresponding dicarboxylic acid were found.

Animal Groups of 30 male Wistar rats were dosed orally, by gavage, with azelaic (C9), sebacic (C10), undecanedioic (C11),

or dodecanedioic (C12) acid.47 Ten rats in each group were dosed with 20, 50, or 100 mg of the respective acid. Blood,

urine, and feces from the treated rats were analyzed and compared to the blank control obtained from untreated rats. (None of

the C9-C12 acids were found in the blank controls.) In urine, approximately 2.5% of azelaic, 2.1% of sebacic, 1.8% of unde-

canedioic, and 1.6% of dodecanedioic acid was recovered after 5 days; the amount recovered was not affected by dosage.

The dicarboxylic acids were not excreted in conjugated form. None of the C9-C12 dicarboxylic acids were recovered in the

feces. In the plasma, dicarboxylic acid catabolites that were 2-, 4-, or 6-carbons shorter than the corresponding dicarboxylic

acid were detected.

Human Groups of 3 male and 2 female subjects were also dosed with azelaic, sebacic, undecanedioic, or dodecanedioic acid

orally, in gelatin capsules, once a wk for 5 wks.47 The dose administered increased each week, from 0.5 g at wk 1 to 5.0 g at

wk 5. None of the C9-C12 acids were found in the blank control samples of blood, urine, and feces obtained from non-treated

humans. In urine, approximately 60% of azelaic, 17% of sebacic, 5% of undecanedioic, and 0.1% of dodecanedioic acid was

recovered after 12 h; the amount recovered was not affected by dosage. At 24 h, the amounts recovered were not much

increased. Initially, undecanedioic and dodecanedioic acid administration raised the urinary pH to a value of 7.4-8.5; the pH

returned to normal within 3-6 h. The dicarboxylic acids were not excreted in conjugated form. None of the C9-C12

dicarboxylic acids were recovered in the feces. In the plasma, dicarboxylic acid catabolites that were 2-, 4-, or 6-carbons

shorter than the corresponding dicarboxylic acid were detected. Plasma levels of azelaic acid peaked at 2 h, while the levels

of the other three acids peaked at 3 h. Recovery in the plasma was greatest for azelaic acid, 74.6 µg/ml with the 5 g dose, and

the amount detected decreased with increasing chain length.

Azelaic Acid

In animals, following an oral dose of azelaic acid, 40% of the radioactivity was recovered in the urine over 5 days, and 14.5% was found in expired carbon dioxide at 48 h. Mostly dicarboxylic acid metabolites were found in the blood for up to 72 h after dosing. Radioactivity was found in all tissues, with the greatest levels in the liver, lungs, and kidneys; levels then decreased in all organs, except the adipose tissue for which an increase continued.

Azelaic acid is a dietary constituent found in whole grain cereals and animal products.48 It can be formed endoge-

nously from longer-chain dicarboxylic acids, metabolism of oleic acid, and ψ-oxidation of monocarboxylic acids.49 Endoge-

nous plasma concentration and daily urinary excretion of azelaic acid are highly dependent on dietary intake. Azelaic acid

crosses the blood-brain barrier.50

A group of 25 male Wistar rats were dosed orally, by gavage, with 100 µCi of [1,9-14C]azelaic acid, and the animals

were killed at various intervals 1-96 h after dosing.47 After 12 and 48 h, 13 and 14.5% of the radioactivity was found in

expired carbon dioxide, respectively. Approximately 40% of the radioactivity was recovered in the urine over 5 days. The

C7 and C5 dicarboxylic acid metabolites were found in the urine up to 72 h after dosing. Very little was recovered in the

feces. Labeled dicarboxylic acids were present in the blood for up to 72 h, and consisted mainly of dicarboxylic acid metabo-

lites. Radioactivity was found in all tissues, with the highest levels present in the liver, lungs, and kidneys after 12 h. Tissue

radioactivity levels then decreased slowly in all organs except adipose tissue, in which case increasing levels were still seen at

96 h. Approximately 90% of the radioactivity found in the tissues was present in the lipids, and it was essentially localized in


10

the fatty acid portion of the triglycerides and of the phospholipids. Traces of C9, C5, and C7 dicarboxylic acids were

detected in the first 24 h.

Sebacic Acid

Sebacic acid is oxidized to water and carbon dioxide, passing through acetyl-CoA and succinyl-CoA formation.51

Disodium Sebacate

In rats, 24h following a single i.v. administration of disodium sebacate, 34.6% of the dose of the dose was recovered in the urine as sebacate and 5% was recovered as suberic acid. A total of 25% of the sebacate was recovered in expired carbon dioxide. No appreciable radioactivity was found in the body. Following i.p. administration of 6 doses of 10-320 mg, sebacate renal clearance was a concentration-independent function. With oral administration, the relative bioavailability was 69%. In humans given a steady infusion of disodium sebacate, less than 15% of the dose was recovered in the urine. The percent oxidation of sebacate was 6.14%.

Animal Disodium sebacate, 80 and 160 mg with 25 µCi of (1,10) [14C]sebacic acid tracer, was administered by a single i.v.

injection to 14 male Wistar rats, and blood samples were obtained at various intervals 5-320 min after dosing.51 The plasma

half-life of radioactive disodium sebacate was 37.86 and 39.82 min for the 80 and 160 mg dose groups, respectively. The

apparent volume of distribution was 2.65 ml/100 g body wt.

In a second experiment, a group of 4 male Wistar rats were given a single dose 160 mg disodium sebacate with 25

µCi sebacic acid tracer by i.v. injection, and expired carbon dioxide, urine, and feces were collected. The carbon dioxide

half-life for radioactive sebacate was 93.64 min; 25% of the administered dose was expired in carbon dioxide. A total of

34.6% of sebacate was recovered in the urine in 24 h, while 5.08% suberic acid (C8) was recovered in the same time frame.

Most of the excretion occurred in the first 4 h. Radioactivity was not found in the feces.

In the third experiment, groups of 10 male Wistar rats were also given 160 mg disodium sebacate with 25 µCi

sebacic acid tracer by i.v. injection, and the animals were sacrificed at various intervals from 30-360 min after dosing. The

amount of radioactivity in various organs was analyzed. No appreciable radioactivity was found in the body. Sebacate

appeared to be in an absorption phase in fat 1 h after dosing, but no radioactivity was found in the body after 24 h.

The pharmacokinetics of disodium sebacate was studied in male and female Wistar rats.52 Sebacate was admini-

stered either i.p., 6 doses of 10-320 mg, or orally, 2 doses of 80 or 60 mg. Plasma concentrations of sebacate and urinary

concentrations of sebacate and its products of β-oxidation (suberic and adipic acids) were measured using GLC/mass spec-

trometry. Both renal and non-renal elimination parameters were obtained. The sebacate half-life was 31.5 min. The tissue

elimination rate was 0.0122 min-1, and the overall volume of distribution was 26.817 ml/100 g. The renal clearance was

0.291 ml/min/100 g, which was much less than the value of the glomerular filtration rate (GFR) of approximately 1

ml/min/100g reported elsewhere, suggesting the presence of sebacate reabsorption from the ultrafiltrate. Sebacate renal

clearance was found to be a concentration-independent function, suggesting the presence of a passive back-diffusion. The

relative bioavailability of the oral route compared to the i.p. route was 69.09%, showing an extensive absorption of the

compound.

Human The metabolism and excretion of disodium sebacate was studied in 7 fasting male subjects that were given a continu-

ous steady infusion of 20 g unlabeled disodium sebacate over 480 min.53 At 240 min into the infusion, (1,10)[C14]sebacic

acid was infused simultaneously as a tracer (sp. act. 0.416 µCi/min). The was a gradual increase in the amount of radioacti-

vity expired in carbon dioxide for the first 300 min; the value remained elevated for an additional 120 min before declining.

At 24 h, 11.38 mmol sebacate was recovered in the urine, as well as 2.04 mmol suberic acid and 1.11 mmol adipic acid,


11

which was less than 15% of the dose administered. The serum concentration of unlabeled sebacate reached a plateau after

270 min of infusion. Ten to 15% of serum radioactivity was found in the aq. fraction of serum extracts. The renal clearance

rate was 5.67 ml/min. The overall tissue uptake of unlabeled sebacate was 180 µmol/min, and the apparent distribution

volume was 12.46 l. The percent oxidation of sebacate was 6.14%.

The pharmacokinetic profile of disodium sebacate during a short-time infusion (5 h at 10 g/h) was also studied in 7

male subjects.54 Sebacate in serum and urine was measured by HPLC. The apparent volume of distribution of sebacate was

8.39 l, and the plasma fractional removal rate constant was 0.0086 min-1.

Six male subjects were given a single i.v. bolus of 1 g disodium sebacate, while another 6 received 10 g of sebacate

in 500 ml of distilled water, i.v., at a rate of 3.33 g/h over 3 h.55 For the group given a bolus dose, the distribution phase had a

short half-life, 0.34 h, and a rapid elimination, 2.045 h-1. For the group given the 3 h infusion, 12% of the dose was excreted

as sebacic acid in 24 h; suberic acid (C8) and adipic acid were also present in the urine.

Dodecanedioic Acid

Approximately 50% of an oral dose of dodecanedioic acid was recovered in the urine of rats, and the C10, C8, and C6 metabolites were found up to 72 h after dosing. Labeled dicarboxylic acid was found in the blood for up to 72 h after dosing, mainly as the dicarboxylic acid metabolites. Radioactivity was found in all tissues, with the highest levels in the liver, lungs, and kidneys; after 24 h, the levels declined in all tissues except adipose tissue.

A group of 25 male Wistar rats were dosed orally, by gavage, with 100 µCi of [10,11-3H]dodecanedioic acid, and

the animals were killed at various intervals 1-96 h after dosing.47 Approximately 50% of the radioactivity was recovered in

the urine over 5 days. The C10, C8, and C6 dicarboxylic acid metabolites were found up to 72 h after dosing. Only 2% of

the radioactivity was recovered in the feces. Labeled dicarboxylic acids were present in the blood for up to 72 h, and

consisted mainly of dicarboxylic acid metabolites. Radioactivity was found in all tissues, with the highest levels present in the

liver, lungs, and kidneys after 24 h. Tissue radioactivity levels then decreased slowly in all organs except adipose tissue, in

which case an increase in radioactivity was still seen at 96 h. Radioactivity levels were 20-40% lower in the lipid extracts of

the tissues than in the residual matter. 3H was distributed in the whole molecule, not only the fatty acid portion, of the

phospholipid and triglyceride fractions. Traces of C12, C10, C8, and C6 dicarboxylic acids were detected in the first 24 h.

Male Wistar rats were given an i.v. bolus of 800 µmol/kg disodium dodecanedioic acid.56 The apparent volume of

distribution was 0.248 l/kg, and the plasma half-life was 12.47 min. The renal clearance was 0.00051 l/kg/min, while

systemic clearance was 0.0138 l/kg/min. Only 3-5% of the dose was recovered in the urine.

Percutaneous Absorption

Azelaic Acid

In humans, the dermal and oral administration of a 20% azelaic acid cream was compared. A total of 2.2% of the dose was recovered in the urine after dermal administration, as compared to 61.2% following oral administration. The calculated percutaneous absorption was determined to be 3.6%.

Vehicle affects the absorption of azelaic acid.44 After a 12 h period, absorption from a 15% azelaic gel was 8%,

while absorption from a water-soluble polyethylene glycol ointment base was only 3%. (Species and details not given.)

The in vitro percutaneous absorption of a 15% azelaic acid gel through human skin, prior to or after the application

of three different moisturizer formulations, was determined.57 All doses were applied as 5 µl/cm2. The second dose was

applied 15 min after the first. [14C]Azelaic acid had a finite dose absorption profile, with a rise to peak penetration followed

by a slow but steady decline. In vitro, 70% of the azelaic acid diffused into the reservoir solution over 48 h. The application

of a moisturizer, and whether it was applied prior to or following azelaic acid administration, did not have a statistically

significant effect on the penetration of azelaic acid. However, there was a trend toward greater percutaneous penetration and


12

mass distribution with the application of a moisturizer lotion prior to the azelaic acid gel.

The percutaneous absorption of azelaic acid was determined using 6 male subjects. A total of 5 g of a cream

containing 20% azelaic acid was applied to the face (1 g), chest (2 g) and upper back (2 g) of each subject, giving an area

dose of approx 5 mg cream/cm2 skin. The test areas were covered 1 h after dosing with cotton tissues, and washed 24 h after

dosing. After 1 wk, 100 ml of an aq. microcrystalline suspension containing 1 g azelaic acid was given orally to each subject.

Urinary excretion of unchanged azelaic acid was measured after each dose. Following dermal application, 1.29% of the dose

was recovered unchanged in the urine in 24 h, and a total of 2.2% was recovered by day 3. Following oral administration,

61.2% of the dose was recovered within 4 h; excretion was complete at this point. Assuming similar rates and pathways in

biotransformation following both routes of exposure, percutaneous absorption of azelaic acid was determined to be 3.6% of

the dermally applied dose.58

Peroxisome Proliferation

Adipic Acid

The effect of adipic acid on hepatic peroxisome proliferation was evaluated in an in vivo study in which 4 male F344

rats were fed chow containing 2% adipic acid dissolved in alcohol.59 After 3 wks of dosing, the animals were killed. Adipic

acid did not induce peroxisome proliferation and did not affect relative liver to body weight.

Cellular Effects

Dicarboxylic acids have a cytotoxic effect on the abnormally hyperactive and malignant epidermal melanocytes.

Dicarboxylic acids, C8to C13, have been shown to inhibit mitochondrial oxidoreductases,60 and they have been shown to

reversibly inhibit microsomal NADPH and cytochrome P450 reductase.61 Medium chain length dicarboxylic acids are also

competitive inhibitors of tyrosinase in vitro.

Adipic Acid

The effect of adipic acid on primary keratinocyte cultures was evaluated using epidermal cells from neonatal NMRI

mice.62 Concentrations of ≤30 mM did not inhibit 3H-thymidine incorporation or affect DNA synthesis, while 40 and 50 mM

inhibited both of these parameters. No effect on labeling indices was observed with 1-30 mM adipic acid.

Azelaic Acid

Azelaic acid, a naturally occurring competitive inhibitor of tyrosinase, has a cytotoxic effect on malignant melano-

cytes .63 Azelaic acid is also a competitive inhibitor of a number of oxidoreductive enzymes, enzymes involved in DNA

synthesis, and of oxidoreductases of the respiratory chain.64 It has been reported that, in vitro, azelaic acid has time- and

dose-dependent, reversible, and anti-proliferative and cytotoxic effects on a number of tumoral cell lines. Azelaic acid had no

effect on normal cell lines.

Mitochondrial suspensions incubated in the presence of 10 mM azelaic acid revealed a 40% inhibition of ATP

synthesis.65 The researchers stated that intracellular ATP levels are crucial for ATP-binding to the tyrosine kinase ATP-

binding domains affecting receptor tyrosine kinase phosphorylation and activation of other downstream kinase- and ATP-

dependent enzymne cascades. The researchers then suggested that these observations could suggest that azelaic acid-induced

depressoin of cellular ATP levels may attenuate the activity of the fibroblast growth factore receptor-2-signaling cascade.

Disodium Azelate

Disodium azelate inhibited cell proliferation and affected viability of Cloudman and Harding-Passey murine melano-

mata at concentrations ≥10-2 M when incubated over a 3 day period.60 The mitochondria were the prime target of action.

The effect of disodium azelate on primary keratinocyte cultures was evaluated using epidermal cells from neonatal


13

NMRI mice.62 A dose-dependent inhibition of 3H-thymidine incorporation into DNA, ranging from 50% inhibition with 20

mM to 90% inhibition with 50 mM disodium azelate, was observed following a 12 h incubation period. Concentrations of 1

and 10 mM did not affect DNA synthesis, but a marked reduction was seen with 20-50 mM. The effects on DNA synthesis

were time-dependent, with the maximum inhibitory effect observed at 4 h; this effect was reversible. RNA and protein syn-

thesis were also inhibited during the first 4 h of incubation with 50 mM disodium azelate. Cellular structure was altered upon

incubation with disodium azelate, primarily affecting mitochondria, and the rough endoplasmic reticulum. These effects were

also reversible.

Dodecanedioic Acid

The disodium salt of dodecanedioic acid inhibited cell proliferation and affected viability of Cloudman and Harding-

Passey murine melanomata at concentrations ≥10-2 M, when incubated over a 3 day period.60 The mitochondria were the

prime target of action.

ANIMAL TOXICOLOGY

Acute Toxicity

The oral LD50 values of the dicarboxylic acids had a wide range, for example, adipic acid had values for rats ranging from 0.94 g/kg to ≥11 g/kg. Most reported values for the acids were >2 g/kg. The reported dermal LD50 values ranged from >6 g/kg dodecanedioic acid to >10 g/kg glutaric acid.

The acute oral, dermal, inhalation and parenteral toxicity of the dicarboxylic acids and some of the salts are

summarized in Table 4.45,66-71

Short-Term Oral Toxicity

In short-term oral toxicity studies, ≤3000 mg/kg bw/day adipic acid did not produce significant toxicological effects in rats. Signs of toxicity were seen at >3600 mg/kg bw/day. No toxicity was observed with guinea pigs fed 400-600 mg/day adipic acid.

Adipic Acid

Groups of 6 male Sprague-Dawley rats were dosed orally (method not specified) with 3600-5600 mg/kg bw adipic

acid as an 18.6-24.9% solution in saline for 14 days.45 Three animals of the 3600 mg/kg bw group, 5 of the 4000 mg/kg bw

group, and all of the 4500-5600 mg/kg bw groups died prior to study termination. Signs of toxicity included depressed

activity, labored respiration, ataxia, and convulsions. No gross findings were noted at necropsy at study termination.

Groups of 5 rats were dosed with 0 or 3000 mg/kg bw of a neutralized 20% adipic acid solution orally, by gavage,

for 4 wks. A non-significant decrease in body weight gain was observed. In a 4 wk study in which a group of 3 rats was

dosed orally, by gavage, with 2400 mg/kg bw adipic acid, no significant toxicological effects were noted.

In a 4-wk dietary study in which groups of 17-20 female rats were fed 0-40 mg/day (0-435 mg/kg bw/day) adipic

acid, no effects were reported. The no-observable adverse effect level (NOAEL) was >435 mg/kg bw/day. In a 5-wk dietary

study in which groups of 15-18 male rats were fed 0-800 mg/day (0-13,333 mg/kg bw bw/day) decreased body weight gains,

an unkempt appearance, and diarrhea were observed for the animals fed 800 mg/day the first 3 wks. In another 5-wk dietary

study in which groups of 4 rats, gender not specified, were fed 100 or 200 mg/day (310-922 mg/kg bw/day) of a 20% adipic

acid solution in ethanol, 5 days/wk, no signs of toxicity were observed.

Ten rats were dosed orally, method not specified, with 199 mg/day (638-1332 mg/kg bw/day) sodium adipate, 5

days/wk for 9 wks. No toxicological effects were observed.


14

A group of 5 guinea pigs, gender not specified, were dosed orally using capsules with 400 mg/day (682-942 mg/kg

bw/day) adipic acid for 5 days, followed by dosing with 600 mg/day (1032-1739 mg/kg bw/day), 5 days/wk for 5 wks. No

signs of toxicity were observed.

No toxicity was observed in a study in which pigs were fed 1% adipic acid in the diet for 7 days.

Short-Term Inhalation Toxicity

Short-term inhalation exposure to 126 mg/m3 adipic acid dust to rats did not produce signs of toxicity, but exposure of mice to 460 mg/m3 did.

Adipic Acid

Mice, gender and number per group not specified, were exposed to 460 mg/m3 adipic acid dust for 1.5 mos.45

(Details of exposure were not specified.) Decreased weight gain, altered oxidase activity, and upper respiratory tract, liver,

kidney, and central nervous system effects were observed. (Details were not given.)

Two male and 2 female rats were exposed to 126 mg/m3 adipic acid dust for 15 days, 6 h/day. No signs of toxicity

were observed, and no gross or microscopic findings were noted at necropsy.

Subchronic Oral Toxicity

In a subchronic oral study, 10 male and 10 female rats exposed to 10% sodium succinate in the drinking water died, but no compound-related lesions were found. Body weights were decreased in rats given ≥2.5% sodium succinate for 13 wks, but toxicological treatment-related changes were not observed. Glutaric acid had a low degree of toxicity to rats (at 2%) and dogs (concentration not specified) when given in the drinking water. Dietary administration of ≤3400 mg/kg bw/day adipic acid for 19 wks produced slight effects in the liver of male rats; the NOAEL was 3333 mg/kg bw. A mixture of adipic, glutaric, and succinic acids had a low degree of toxicity in rats when tested at 3% for 90-days.

Sodium Succinate

The oral toxicity of sodium succinate was evaluated using F344 rats.70 Groups of 10 males and 10 females were

given 0, 0.3, 0.6, 1.25, 2.5, 5 or 10% sodium succinate in the drinking water for 13 wks. All animals were killed at the

termination of dosing. Body weight gains of animals of the 10% group were significantly decreased, and all animals of this

group died by wk 4. These animals were extremely emaciated; however, no compound-related microscopic lesions were

found. Body weight gains were decreased in animals given ≥2.5% sodium succinate, as compared to controls. No toxicologi-

cal treatment-related effects were observed.

Glutaric Acid

Groups of 15 male and 15 female Sprague Dawley rats were fed a diet containing 0-2% glutaric acid for 90-days.67

Body weight gains were decreased for males and statistically significantly decreased for females of the 2% group. No differ-

ences were noted between test and control animals in hematology, clinical chemistry, or urinalysis. There were no micro-

scopic findings or organ weight changes attributable to the test substance. There was no treatment-related mortality. The

NOAEL was ≥1%, and the LOAEL was 2% glutaric acid.

Four male and 4 female Beagle dogs were fed a diet containing 0-5% glutaric acid for 90 days. Decreased body

weights, accompanied by reduced feed consumption, were observed for the males and females of the 5% group and females of

the 3% group. No other treatment-related effects were observed. The NOAEL was ≥2% and the LOAEL was 3%.

Adipic Acid

Groups of 8-10 male rats were given 0, 420, 840, 1700, or 3400 mg/kg bw/day sodium adipate for 19 wks in a

protein deficient diet.69 Animals were killed after either 7 wks or at study termination. For unexplained reasons, only 5-7

animals/group survived until study termination. Rats of the 3400 mg/kg bw/day group had decreased body weight gains and

decreased body weights. (Statistical significance not stated.) Slight effects were seen in the liver, and the NOAEL was 3333


15

mg/kg bw.

Adipic/Glutaric/Succinic Acid Mixture

Groups of 15 male and 15 female rats were dosed orally, by gavage, for 90 days with 0-30% of a mixture that con-

tained 4% adipic, 16% glutaric, and 5% succinic acid.67 The vehicle was deionized water, and the dosing volume was 10

ml/kg. Two males and 1 female of the 30% group died, and the deaths were considered dose-related. Also in this group,

body weights were reduced for males and females, and feed consumption was statistically significantly reduced in males. An

increased incidence of labored breathing and rales was noted. The urine pH was statistically significantly reduced in both

males and females dosed with 30% of the mixture. In the 10% group, body weight gains were slightly, but not statistically

significantly, reduced in females and feed consumption was statistically significantly reduced in males. The NOAEL was 3%

and the LOAEL was 10%.

Subchronic Inhalation Toxicity

Signs of toxicity were reported in a subchronic inhalation study in which mice were exposed to 13 or 129 mg/m3 adipic acid.

Adipic Acid

Mice, gender and number per group not specified, were exposed to 13 or 129 mg/m3 adipic acid for 4 mos.45

(Details of exposure were not specified.) Decreased weight gain, altered oxidase activity, and upper respiratory tract, liver,

kidney, and central nervous system effects were observed.

Chronic Oral Toxicity

Slight effects were seen in the livers of rats fed ≤3200 mg/kg bw/day adipic acid for 33 wks, and the NOAEL for rats fed a diet containing adipic acid for 2 yrs was 1%; no significant toxicological effects were seen at concentrations of ≤5%. No significant toxicological effects were observed for mice fed ≤280 mg/kg bw or rabbits fed ≤400 mg/kg bw azelaic acid for 180 days. Disodium sebacate was not toxic to rats or rabbits fed up to 1000 mg/kg bw for 6 mos.

Adipic Acid

Groups of 13-15 male and female rats were fed a diet containing 0, 1600, or 3200 mg/kg bw/day adipic acid for 33

wks.45 Rats were killed at various intervals throughout the study. Ten of 14 rats fed 3200 mg/kg bw/day died during wks 0-4;

surviving rats had decreased weight gains during this time. However, at study termination, body weights were for surviving

animals of this group were similar to controls. Slight effects were seen in the liver. (Statistical significance not stated.)

In a 2-yr study, groups of 20 male rats were fed a diet containing 0, 0.1, 1, 3, and 5% adipic acid (equiv. to 0, 75,

750, 2250, and 3750 mg/kg bw/day), and groups of 10 and 19 females were fed 0 and 1% adipic acid, respectively. Weight

gains of male rats fed 3 and 5% adipic acid were significantly less than controls. There were no significant toxicological

findings upon gross or microscopic observation. The NOAEL was 1% adipic acid for male and female rats.

Azelaic Acid

Groups of 15 male and 15 female Wistar rats were fed a diet containing 140 or 280 mg/kg bw azelaic acid for 180

days, and a control group of 10 males and 10 females was given untreated feed.71 No significant toxicological effects were

observed. Growth was similar between test and control groups, as were the microscopic examinations and clinical chemistry

parameters. The researchers found similar, negative, results when groups of 10 male and 10 female New Zealand rabbits

were fed diets containing 0, 200, or 400 mg/kg bw azelaic acid for 180 days.

Disodium Sebacate

Groups of 10 male and 10 female Wistar rats were fed a diet containing 0, 500, or 1000 mg/kg bw disodium sebacate


16

for 6 mos, after which time they were killed and necropsied.66 Growth was similar between test and control groups, as were

the microscopic examinations and clinical chemistry parameters. The researchers found similar, negative, results when

groups of 10 male and 10 female New Zealand rabbits were fed diets containing 0, 750, or 1000 mg/kg bw disodium sebacate

for 6 mos.

Ocular Irritation

For the dicarboxylic acids, the severity of ocular irritation seems to decrease with increasing carbon number. Tested undiluted, succinic acid was a severe ocular irritant, glutaric acid was moderately irritating, and dodecanedioic acid was a slight irritant. Ocular irritation produced by adipic acid was dose-dependent.

Ocular irritation studies are summarized in Table 5.

Succinic Acid

The ocular irritation potential of succinic acid was evaluated using albino rabbits67 Undiluted test material, 0.005

ml, was applied to the center of the cornea. The eyes were not rinsed. Succinic acid was a severe eye irritant, with necrosis

visible upon staining. The score for ocular irritation, on a scale of 1-10, was 8.

Glutaric Acid

A Draize ocular irritation study was performed in which 100 mg of glutaric acid was applied to the eyes of 3 rabbits

and the eyes were rinsed 24 h after application.67 Glutaric acid was irritating to rabbit eyes, with a primary irritation index

(PII) of 35.2/110. Mild erythema, slight edema, and slight dullness were still present after 7 days.

Adipic Acid

The ocular irritation of adipic acid was evaluated using groups of 2 albino rabbits.67 Ten or 57.1 mg of adipic acid

was placed in the eye of each rabbit, and the eye of 1 animal in each group was rinsed. With 10 mg followed by rinsing, mild

conjunctival irritation was observed; and the eye was normal within 3 days. In the unrinsed eye, mild conjunctival irritation

and a minimal iritic effect were observed; minimal conjunctival irritation was still observed after 7 days and the eye was

normal after 14 days. With instillation of 57.1 mg adipic acid followed by rinsing, moderate to mild conjunctival irritation

and transient mild opacity were observed; the eye was normal in 3 days. In the unrinsed eye, moderate to mild conjunctival

irritation, mild opacity of the cornea, and a minimal iritic effect were observed; the eye was normal at day 7. However, other

studies have reported that adipic acid produced severe irritation in rabbit eyes, and the signs of irritation were still present

after 8 days.45


The ocular irritation potential of a mixture of adipic, glutaric, and succinic acid, percentages not specified, was eval-

uated using 2 male albino rabbits.67 One-tenth ml of the test substance was placed in the conjunctival sac of each animal, and

the eye of one animal, but not the other, was rinsed. The contralateral eye served as the negative control. Mild to severe con-

junctivitis was observed in on both the rinsed and unrinsed rabbit eyes. Both eyes were normal within 21 days.

Dodecanedioic Acid

In studies using rabbits that evaluated the ocular irritation of dodecanedioic acid, slight irritation was reported in one

study, with a PII of 11.96/110, and small areas of corneal opacity and mild conjunctival irritation were seen in the other

study.68 Details were not provided.

Dermal Irritation/Sensitization

Slight to mild dermal irritation was observed for succinic, glutaric, and adipic acid. Adipic acid, dodecanedioic acid, and a mixture of succinic, glutaric, and adipic acids are not sensitizers.

Dermal irritation and sensitization studies are summarized in Table 6.


17

Succinic Acid

Succinic acid was a slight irritant to rabbit skin.67 Details were not provided.

Glutaric Acid

The dermal irritation potential of glutaric acid was determined using 2 male and 4 female New Zealand white

rabbits.67 A 0.5 g aliquot of glutaric acid was applied to the clipped skin on the back of the rabbits. The test site was scored

for irritation after 3 min, and the site was then washed. The test material was then applied to two other test sites, which were

covered with a rubber wrap. The sites were examined at 1 and 4 h, and the site was washed after both examinations. The

sites were then evaluated at 24 and 48 h after application. Slight erythema was seen in one rabbit throughout the study.

Irritation was not observed in the other rabbits.

Adipic Acid

A dermal irritation study was performed in which 500 mg of 50% aq. adipic acid was applied under an occlusive

patch to a 5 cm x 5 cm area of intact and abraded skin of 6 rabbits for 24 h.45 With intact skin, an erythema score of 2-3/4

was reported, with clearing by day 3. With abraded skin, mild to severe erythema and edema were reported, which cleared by

day 7.

Adipic acid, undiluted or as an 80% aq. paste, was applied occlusively to the backs or ears of rabbits for 24 h. Two

rabbits were used per group. No irritation was observed on the backs of animals. Erythema was observed on the ear, with

clearing by 72 h. In another study in which adipic acid was applied occlusively for 24 h, irritation was not observed. Details

were not provided.

A semi-occlusive application of 500 mg of a paste of 50% adipic acid in propylene glycol to 6 rabbits produced

slight to mild irritation in 3 of the rabbits. A semi-occlusive application of undiluted adipic acid was not corrosive. Adipic

acid, 50% in propylene glycol, was not irritating to a group of 10 guinea pigs.

The sensitization potential of adipic acid was evaluated using groups of 10 guinea pigs. For induction, 0.1 ml of 1%

aq. adipic acid was given as a sacral intradermal injection, once a week for 4 wks. After a 2-wk non-treatment period, the

dermal challenge was performed with 0.05 ml of 50 and 25% adipic acid in propylene glycol. Adipic acid produced very

mild or no irritation and it was not a sensitizer.


A mixture of adipic, glutaric, and succinic acid (percentages not specified) was evaluated for irritation and for sensi-

tization using groups of 10 male guinea pigs.67 The primary irritation potential was evaluated by applying 0.05 ml of an 8 or

80% suspension in dimethyl phthalate to the shaved, intact skin on the shoulder of the animals. The sensitization potential

was also evaluated, using 4 sacral intradermal injections of 0.1 ml of a 1% suspension for induction. After a 13-day non-treat-

ment period, a dermal challenge was performed with 0.05 ml of an 8% and 80% suspension of the mixture. Ten previously

untreated guinea pigs were exposed to the same challenge applications as the test animals. In the test for primary irritation,

the 8% suspension produced no irritation, and no to mild irritation was observed 24 h after exposure to the 80% suspension.

No sensitization was observed at either dose.

Dodecanedioic Acid

Dodecanedioic acid was not an irritant to rabbit skin in a 4-h exposure study or upon application of 0.5 g.68 In a

maximization study using female guinea pigs, 0.5% dodecanedioic acid was injected intracutaneously at induction and 25 and

50% was used for the dermal challenge. Dodecanedioic acid was not a sensitizer.


18

Mucosal Irritation

Succinic Acid

Succinic acid has been considered to be an exacerbating factor in ulcerative colitis, therefore its influence on rat co-

lonic mucosa in terms of mucosal blood flow and superoxide generation was investigated.72 The left side of the colon of 5

male and 5 female rats was exposed, and 0.9-5% succinic acid in physiological saline was instilled into the colonic lumen. A

segment of the colon was then ligated as to not include the mesenteric blood vessel. Mucosal blood flow decreased with all

dose levels. Microscopically, the higher the concentration of succinic acid, the greater was the erosion formation in the colon-

ic mucosa. Significant polymorphonuclear cell infiltration superoxide generation from colon tissue was observed with 0.01%

succinic acid, as compared to higher or lower concentrations. Succinic acid, at fecal concentrations found in active stage

ulcerative colitis, appears to be implicated in mucosal injury, mediated by a decrease in colonic mucosal blood flow and infil-

tration of superoxide-generating polymorphonuclear cells into the mucosa.

REPRODUCTIVE AND DEVELOPMENTAL TOXICITY

Reproductive and developmental effects were not seen upon oral dosing with the dicarboxylic acids or disodium sebacate. Malonic acid has a spermicidal effect on human spermatozoa in vitro. Glutaric acid was tested at doses of ≤1300 mg/kg bw in rats and 500 mg/kg bw in rabbits, adipic acid at doses of ≤263 mg/kg bw in mice, 288 mg/kg bw in rats, 205 mg/kg bw in hamsters, or 250 mg/kg bw in rabbits, azelaic acid at doses of ≤140 mg/kg bw in rats and 200 mg/kg bw in rabbits, disodium sebacate at 500 mg/kg bw in rats and 1000 mg/kg bw in rabbits, and dodecanedioic acid was tested at ≤1000 mg/kg bw using rats. Embryotoxic effects were reported in a reproductive study of 2500 mg/kg bw/day azelaic acid using rats and in reproductive studies with ≤500 mg/kg bw/day azelaic acid using rabbits and monkey. In vitro, sodium salts of some dicarboxylic acid had a specific inhibitory effect on muscle activity the uterine horn, and this effect progressively increased with chain length.

Malonic Acid

Malonic acid, 0.1%, reduced the pH of sperm suspensions from 7.5 to 4.5-5.5 and it rendered human spermatozoa

immotile within 30 min.73 A concentration of 1.0% reduced the pH to 1.5-3.0 and was almost instantaneously spermicidal.

Succinic Acid

Thirty ovariectomized female rats were given daily subcutaneous injections of 5.0 mg/day succinic acid for 3 wks.67

Ten females were used as controls. Daily vaginal smears were similar for test and control animals. Microscopically, no

changes were seen in the uterine horn, cervix, or vagina of the animals.

Glutaric Acid

The reproductive toxicity of glutaric acid was evaluated using groups of 25 female rats.67 The animals were dosed

orally, by gavage, with 0, 125, 400, or 1300 mg/kg glutaric acid on days 6-15 of gestation, and the animals were killed on day

20 of gestation. No toxicological or reproductive effects were observed for the 125 mg/kg group. In the 400 mg/kg group,

salivation, rales, and nasal discharge were observed. One dam of the 1300 mg/kg group died on day 10 of gestation, and one

was killed due to moribund condition on day 13 of gestation. Mean body weight gains were decreased in the 1300 mg/kg

group during dosing, but body weight gains in this group were normal post-dosing. Clinical signs of toxicity in the 1300

mg/kg group included salivation, rales, nasal discharge, and staining around the mouth, nares, and anogenital area. No

adverse effects on pregnancy and no teratogenic effects were reported at any of the dose levels. There was a significant

increase in resorptions in the 1300 mg/kg group compared to controls, but the value was within normal expected limits and,

therefore, not considered biologically meaningful.

Groups of 18 gravid female New Zealand white rabbits were dosed orally, by gavage, on days 6-18 of gestation with

0, 50, 160, or 500 mg/kg glutaric acid, and the animals were killed on day 29 of gestation. No test-article related mortality

occurred. There were no clinical signs of toxicity, and body weights were not affected. No embryotoxic, teratogenic, or


19

adverse reproductive effects were reported.

Adipic Acid

Groups of 20-24 gravid albino CD-1 mice were dosed orally, by gavage, with 0, 2.6, 12, 56, or 263 mg/kg bw adipic

acid on days 6-15 of gestation.45 All animals were killed on day 17 of gestation. No reproductive, developmental, or

maternal effects were observed, and the NOAEL for maternal and developmental toxicity was 263 mg/kg bw. Similar results

were obtained in a study in which gravid Wistar rats were dosed orally, by gavage, with 0, 2.9, 13, 62, or 288 mg/kg bw

adipic acid on days 6-15 of gestation. The NOAEL for maternal and developmental toxicity was 288 mg/kg bw.

Groups of 21-24 gravid hamsters were dosed orally, by gavage, with 0, 2.9, 5, 44, or 205 mg/kg bw adipic acid on

days 6-10 of gestation. A significant increase in resorption per implant site was observed with 205 mg/kg bw adipic acid,

resulting in a decreased number of live fetuses. (This decrease was not evaluated statistically.) No other effects were

reported.

Groups of 10-14 gravid Dutch-belted rabbits were dosed by oral intubation with 0, 2.5, 12, 54, or 250 mg/kg bw

adipic acid on days 6-18 of gestation. No reproductive, developmental, or maternal effects were observed. The NOAEL for

maternal toxicity was ≥250 mg/kg bw and for developmental toxicity was 250 mg/kg bw.

Azelaic Acid

Reproductive and teratogenic effects of azelaic acid were evaluated using Wistar rats and New Zealand rabbits.71 A

group of 20 gravid rats was fed a diet containing 140 mg/kg bw/day azelaic acid, and a control group of 10 gravid rats was

given untreated feed. Half of each group was killed and necropsied on day 19 of gestation, and the remaining animals

continued dosing for 3 mos. The day of gestation that dosing started is not clear. No gross or microscopic lesions were

observed for the uteri, placentas, or ovaries. There were no differences in reproductive, teratogenic, or developmental effects

between treated and control groups, nor were there any differences in fetal weights of the live fetuses. Similar results were

seen using groups of 20 gravid rabbits fed 200 mg/kg bw/day azelaic acid; 10 untreated gravid rabbits were used as a negative

control group.

Embryotoxic effects were observed in oral studies with rats receiving 2500 mg/kg bw/day of azelaic acid.49 Similar

effects were observed in studies in rabbits given 150 to 500 mg/kg bw/day and in monkeys given 500 mg/kg bw/day. The

doses at which these effects were noted were all within toxic dose ranges for the dams. No teratogenic effects were observed.

(Details were not provided.)

Disodium Sebacate

Reproductive, teratogenic, and developmental effects of disodium sebacate were evaluated using Wistar rats and

New Zealand rabbits.71 Groups of 20 gravid rats were fed a diet containing 0 or 500 mg/kg bw/day disodium sebacate, and

groups of 20 gravid rabbits were fed 0 or 1000 mg/kg bw. Half of each group was killed and necropsied on day 19 of

gestation, and the remaining animals continued dosing for 3 mos. The day of gestation that dosing started is not clear. No

gross or microscopic lesions were observed for the uteri, placentas, or ovaries. There were no differences in reproductive or

developmental effects between treated and control groups, nor were there any differences in fetal weights of the live fetuses.

Dodecanedioic Acid

The reproductive toxicity of 0-1000 mg/kg bw dodecanedioic acid was evaluated in an OECD combined repeated

doe and reproductive/developmental toxicity screening test using male and female Crl:CD:BR rats.68 The no-observable

effect level (NOEL) for reproductive and developmental toxicity was 1000 mg/kg bw. The NOELs for toxicity of male and

female rats were 100 and 500 mg/kg bw, respectively. The NOAEL for both male and female rats was 1000 mg/kg bw. (No


20

other details were provided.)

Sodium Salt of Adipic, Azelaic, Sebacic, and Dodecanedioic Acids

The influence of the sodium salt of some dicarboxylic acids (adipic acid, azelaic acid, sebacic acid, dodecanedioic

acid) on both spontaneous and evoked muscle activity of the uterine horns of 35 female Wistar rats (250-300g) has been

studied in vitro.74 Spontaneous activity of uterine muscle was inhibited by dicarboxylic salts causing the total abolition of

mechanical events at concentrations of 24, 32, 40, and 64 x 10-3 M. Dicarboxylic salts antagonized the maximal isometric

contraction of the uterine horn induced by administration of acetylcholine, oxytocin or prostaglandins (PGF2-α). The amount

of antagonism was dependent upon the concentration of dicarboxylic salt used. Dicarboxylic salts had an specific inhibitory

effect on the uterine horn which progressively increased with their chain length. The results suggested that the inhibitory

effects of dicarboxylic salts on smooth muscle could be due to a cellular membrane hyperpolarization.

GENOTOXICITY

The dicarboxylic acids are not genotoxic, and consistently were not mutagenic in Ames tests. Positive results were seen in a transformation assay on glutaric acid using Balb/c-3T3 cells, both with and without metabolic activation. The results of a mouse lymphoma assay, with and without metabolic activation, on glutaric acid were negative in a neutral pH range. Equivocal results were obtained in an in vitro chromosomal aberration assay of ≤15 mg/ml disodium succinate using Chinese hamster fibroblast cells. The dicarboxylic acids were not genotoxic in in vivo assays.

Available details for the genotoxicity studies are summarized in Table 7.

In V itro

Malonic Acid

Malonic acid, 3333 µg/plate, was not mutagenic in a National Toxicology Program (NTP) preincubation assay, with

or without metabolic activation.75

Succinic Acid

The genotoxic potential of succinic acid was evaluated in an Ames test and in a chromosomal aberration study using

a Chinese hamster fibroblast cell line.76 Succinic acid, at a concentration of ≤5.0 mg/plate in phosphate buffer, was not muta-

genic in the Ames test. (Whether metabolic activation was used is not stated.) Concentrations of ≤1.0 mg/ml in saline were

not genotoxic in the chromosomal aberration assay.

Disodium Succinate

The genotoxic potential of disodium succinate was evaluated in an Ames test and in a chromosomal aberration study

using a Chinese hamster fibroblast cell line.76 In the Ames test, disodium succinate was not mutagenic at concentration up to

5.0 mg/plate in phosphate buffer. (Whether metabolic activation was used is not stated.) Disodium succinate, ≤10 mg/plate,

was negative in an Ames test, with and without metabolic activation.77

Equivocal genotoxic results were obtained in the chromosome aberration assay of ≤15.0 mg/ml disodium succinate

in saline using Chinese hamster fibroblast cells.

Glutaric Acid

Glutaric acid was evaluated in vitro in a standard Ames assay, the L5178Y/TK ± mouse lymphoma assay with and

without metabolic activation, and the mammalian in vitro Balb/c-3T3 cell transformation assay with and without metabolic

activation.78 The Ames tests were negative. However, the cell transformation assay was positive both in the presence and

absence of metabolic activation and the results in the mouse lymphoma assay were dependent upon pH of the culture medium.

The researchers stated that the variable response in the mouse lymphoma assay and the positive effect in the cell transforma-

tion assay may have been an indirect effect of other factors (such as the pH or osmolarity of the media in which the cells were


21

exposed), rather than a direct effect of glutaric acid.

Adipic Acid

Adipic acid was evaluated in a number of Ames assays using Salmonella typhimurium and Escherichia coli; results

were negative, with or without metabolic activation, at concentrations as high as 10,000 mg/plate.45,79,80 Negative results were

also obtained in an Ames test with 0-200 mg/l adipic acid using S. typhimurium TA1530 and G-46 without metabolic activa-

tion45. Results were negative in a yeast gene mutation assay using Saccharomyces cerevisiae without metabolic activation at

concentrations ≤200 mg/l. A mouse lymphoma assay using L5178Y/TK ± cells was negative with and without metabolic acti-

vation at concentrations of ≤2000 µg/plate,80 as was a cytogenetic assay using human embryonic lung fibroblast cells with

≤200 mg/l adipic acid.45 In a viral enhanced cell transformation assay using Syrian hamster embryo cells at doses of 62-1000

µg/ml adipic acid, results were negative.


A mixture of adipic, glutaric, and succinic acid, percentages not specified, tested as a 50% aq. solution, was not

mutagenic in an Ames assay using S. typhimurium, with or without metabolic activation, at concentrations of ≤300 µg/plate.67

Negative results were also obtained in an unscheduled DNA synthesis assay at concentrations of ≤5000 µg/plate using rat

hepatocytes and in an HGPRT assay at concentrations of ≤2500 µg/plate, without, and of ≤3500 µg/plate, with, metabolic

activation. In an in vitro transformation assay using Chinese hamster ovary (CHO) cells at concentrations of ≤1500 µg/ml

without and ≤2500 µg/ml with metabolic activation, positive results were obtained with, but not without, metabolic activation

at 2000 µg/plate.

Azelaic Acid

Azelaic acid, 20%, was not mutagenic or genotoxic in an Ames assay, HGPRT test in CHO cells, or human

lymphocyte test.49 Details were not provided.

Dodecanedioic Acid

Dodecanedioic acid was not mutagenic in an Ames assay at concentrations of ≤5000 µg/plate, with and without

metabolic activation.68 Toxicity occurred at ≥500 µg/plate.

In Vivo

Glutaric Acid

Glutaric acid was evaluated in a mammalian micronucleus cytogenetic assay in mice.78 Glutaric acid was not

genotoxic in this assay. (Details not specified.)

Adipic Acid

Adipic acid was not genotoxic in in vivo cytogenetic assays using chromosomes from rats dosed orally, by gavage,

with a single dose of 5000 mg/kg bw or daily for 5 days with 2500 mg/kg bw.45 Adipic acid was also not genotoxic in

dominant lethal studies with doses up to 5000 mg/kg bw.


A mixture of adipic, glutaric, and succinic acid, percentages to specified, was not genotoxic in vivo using male and

female Sprague Dawley rats dosed orally by gavage with 2750 and 1375 mg/kg of the mixture, respectively.67

Azelaic Acid

Azelaic acid was not genotoxic in a dominant lethal assay in mice.49 (Details not specified.)

Dodecanedioic Acid

Dodecanedioic acid, ≤5000 mg/kg bw, was not mutagenic in a micronucleus assay using mice.68


22

CARCINOGENICITY

Carcinogenicity was not seen in rats given up to 2% sodium succinate in the drinking water or 5% adipic acid in feed for 2 yrs. An increase in the incidence of C-cell adenoma/carcinoma of the thyroid in females given 2% sodium succinate, and a positive trend in the occurrence of this tumor, was considered a function of experimental variability and not related to dosing. Adipic acid was not carcinogenic when given orally to rats at up to 5% in the diet.

Sodium Succinate

Groups of 50 male and 50 female F344 rats were given drinking water containing 0, 1, or 2% sodium succinate for 2

yrs, and the carcinogenic potential was determined.70 Dosing was discontinued after 104 wks, and, after a 9-wk recovery

period, the rats were killed. Body weights of the high dose animals were decreased by 10% as compared to controls. There

were no statistically significant differences in overall tumor incidence or mean survival time between treated and control

animals. An increase in the incidence of C-cell adenoma/carcinoma of the thyroid in females of the 2% group, and a positive

trend in the occurrence of this tumor, was considered a function of experimental variability and not related to dosing. Sodium

succinate was not toxic or carcinogenic to male or female F344 rats when given in the drinking water for 2 yrs.

Adipic Acid

Adipic acid was not carcinogenic in the 2-yr chronic oral toxicity study (described previously) in which groups of 20

male rats were fed diets containing 0, 0.1, 1, 3, and 5% adipic acid, and groups of 10 and 19 females were fed 0 and 1%

adipic acid, respectively.69

Tumor Promotion

Succinic Acid, Sodium Succinate, Disodium Succinate

The promotion of urinary bladder carcinogenesis by sodium succinate was evaluated using male F344 rats.81 Groups

of 16 male F344 rats were given 5% succinic acid, sodium succinate, or disodium succinate with 0.05% N-butyl-N- (4-

hydroxybutyl)nitrosamine (BBN) in the drinking water for 4 wks, followed by dietary administration of 5% of the respective

test article without BBN for 32 wks. Negative controls were given water with BBN only and untreated feed. Groups of 8

male F344 rats followed the same protocol without the addition of BBN to the drinking water, as did a group of non-BBN-

treated negative controls. The animals were killed at wk 37.

In the BBN-pretreated groups, many rats given sodium or disodium succinate developed hematuria towards the end

of the study. There were no statistically significant differences in body or organ weights between the control and test groups.

(Information on organ and body weights was not provided for the non-BBN groups.) Large tumors were found on the urinary

bladders of the BBN-pretreated animals given sodium and disodium succinate; tiny lesions were found in the control or

succinic acid BBN-pretreated animals. The incidence and number of urinary bladder carcinomas and papillomas and of papil-

lary or nodular hyperplasia (preneoplastic lesions) were statistically significantly increased in the sodium and disodium

succinate BBN-pretreated groups as compared to the succinic acid and control BBN-pretreated groups. The incidence and

numbers observed in the sodium and disodium succinate groups were not statistically significantly different from each other.

An association between tumor area and sodium intake was noted. Urinary bladder lesions were not observed in any of the

animals that were not pretreated with BBN. Urinary pH and electrolyte concentrations were affected by dosing with sodium

or disodium succinate with BBN, as compared to the control and succinic acid groups, and statistically significant differences

between these two groups were observed as well.

The researchers also evaluated cell proliferation and DNA synthesis in the urinary bladder epithelium. Groups of 20

male F344 rats were given 5% succinic acid, sodium succinate, or disodium succinate in the feed, without BBN pretreatment

for 8 wks. Negative controls were given basal diet. Five rats per group were given an i.p. injection of 50 mg/kg bw 5-bromo-


23

2’-deoxyuridine (BrdU) 1 h prior to being killed. Compared to control values, BrdU uptake was statistically significantly

increased by increased disodium succinate and was increased, but not in a statistically significant manner, by sodium

succinate. Succinic acid did not have any effect on DNA synthesis. Microscopically, simple hyperplasia was observed in the

urinary bladders of animals given sodium and disodium succinate. The appearance of the urinary bladder epithelial surface

was altered by sodium and disodium succinate. Spermidine/spermine N1-acetyltransferase activity in the urinary bladder epi-

thelium was increased for disodium succinate, but not sodium succinate, when compared to controls. Urinary pH and

electrolyte concentrations were affected as described previously.

CLINICAL ASSESSMENT OF SAFETY

In a cumulative irritancy test, the cumulative irritation of a 15% azelaic acid gel increased with successive patching. It is not known if the vehicle played a role in the irritation scores. Daily application of a 20% azelaic cream causes erythema and irritation.

Dermal Irritation

Azelaic Acid

The cumulative irritation potential of a 15% azelaic acid gel (prescription formulation; vehicle not identified) was

determined in a study using 31 female and 2 male subjects.82 (During the study, 1 subject withdrew for personal reasons.)

White petrolatum was used as a negative control. Azelaic acid and petrolatum, 0.2 g of each, were applied under occlusion to

2 cm x 2 cm sites on the back of each subject 3 times per week for 3 wks. Weekday patches were removed after 24 h, while

the patches applied on Fridays were removed after 72 h. The test sites were evaluated 15-30 min after removal of the patch,

and then a new patch was applied. Application was discontinued if severe irritation, which was designated by a maximum

erythema score of 3, was observed. A 15% azelaic acid gel was statistically significantly more irritating than the negative

control, with a mean cumulative irritancy index of 1.05/3. Individual reaction scores for the test article ranged from 0 to 3,

and 5 subjects discontinued patching with azelaic acid due to an irritation score ≥3. Cumulative irritancy increased with suc-

cessive patching. The researchers noted that since the vehicle used for azelaic acid was not tested, there was uncertainty as to

whether the vehicle components affected the irritation scores.

Twice daily application of a cream containing 20% azelaic acid has been reported to cause erythema, irritation,

pruritus, dryness, scaling, and burning.83

Case Reports

Adipic Acid

In two case reports with industrial exposure to adipic acid, positive sensitization reactions were reported with follow-

up testing.45


24

ESTERS OF DICARBOXYLIC ACIDS

Much of the information on the esters of dicarboxylic acids was obtained from summary documents that mostly

contained unpublished data. Data on esterase metabolites other than the parent dicarboxylic acid (i.e. parent alcohol and

monoester) are summarized in Appendix I, immediately following the reference section. It is important to note that this is

merely for support and not for review as ingredients themselves.

GENERAL BIOLOGY

Absorption, Distribution, Metabolism, and Excretion

Metabolism of diesters in animals is expected to occur, initially, via enzymatic hydrolysis, leading to the correspond-

ing dicarboxylic acids and the corresponding linear or branched alcohol.84 These dicarboxylic acids and alcohols can be fur-

ther metabolized or conjugated to polar products that are excreted in urine. However, other studies have shown that enzy-

matic hydrolysis of at least some diesters may be incomplete and result, instead, in the production of monoesters.85

Diethyl Malonate

In in vitro absorption studies using pig skin, 8.8 and 3% of undiluted diethyl malonate was found in the skin and receptor fluid, respectively, after 50 h. Absorption was enhanced when diethyl malonate was diluted with ethanol and reduced when diluted in acetone. Using human skin, 16% of the applied diethyl malonate penetrated in 24 h. In vivo, absorption of diethyl malonate, estimated from urinary and fecal recovery, was 15% in nude mice, 4% in human skin grafted to nude mice, 6% in pig skin grafted to nude mice, 2.5% in pigs, and 4% in dogs.

Diethyl malonate is hydrolyzed via a two-step reaction to malonic acid and the corresponding alcohol, ethanol.14

Dimethyl malonate, which is not listed in the International Cosmetic Ingredient Dictionary, has similar physico-

chemical properties and hydrolyzes in the same manner to malonic acid and methanol. Because of this similarity, data on

dimethyl malonate will be included in this safety assessment to provide read-across data.

Distribution of diethyl malonate (and dimethyl malonate) is likely to occur in the water compartments, and accumu-

lation in fat is unlikely based on physical and chemical properties. Both esters are likely to be metabolized by unspecific

(serine-) esterases of different tissues, in particular, in the liver to the monoesters and then to malonic acid and ethanol (or

methanol). The hydrolysis product is likely to be metabolized via physiological pathways, such as the tricarboxylic acid cycle,

as they are part of the normal intermediate metabolism. Both are assumed to readily absorb via mucous membranes.

In Vitro - Animal The percutaneous absorption of radiolabeled diethyl malonate was determined in vitro using skin from Yorkshire

pigs.14 [2-14C]Diethyl malonate was applied either undiluted (100 µg/cm2) or diluted in ethanol at 12.5 mg/ml with an applied

dose of 100 µg/cm2 or as 0.5 mg/ml with an applied dose of 4 µg/cm2. At 50 h, with undiluted diethyl malonate, 8.8% of the

radioactivity was found in the skin and 3% was in the receptor fluid. With 100 µg in ethanol, 13% of the radioactivity was

found in the skin and 6% in the receptor fluid and with 4 µg in ethanol, 30% was found in the skin and 10% in the receptor

fluid. Absorption appeared to be enhanced with ethanol.

The percutaneous absorption of 1 mg/cm2 [2-14C]diethyl malonate in 10 µl acetone was determined in vitro also

using skin from Yorkshire pigs. At 24 h, 0.2-1.6% of the diethyl malonate was found in the receptor fluid, 0.2-0.9% was

found in the skin, and 0.6-0.7% was found on the skin surface. Skin mediated hydrolysis amounted to 15-35% of the applied

dose. In the receptor fluid, 20-21% of the applied dose was present as hydrolysis products. In the skin and on the skin

surface, 3-5% and 2-4%, respectively, of the applied dose was present as hydrolysis products.

In Vivo - Animal The percutaneous penetration of radiolabeled diethyl malonate was studied in vivo in the following animal models:

athymic nude mouse, human, and pig skin grafted to athymic nude mice, in weanling pigs, and in hairless dogs.14 [2-14C]Di-


25

ethyl malonate was applied at a dose of 0.1 mg/cm2 for 24 h to a 1.27 cm2 area of mouse skin, or for 48 h to a 25 cm2 area of

pigs and hairless dogs using non-occluded applications. According to the authors, the percutaneous absorption, was estimated

from the recovery of radioactivity in urine and feces and corrected for the recovery observed after parenteral (s.c.)

administration. Absorption was 15% in nude mice, 4 % in human skin grafted to nude mice, 6% in pig skin grafted to nude

mice, 2.5% in pigs, and 4% in dogs.

In Vitro - Human An in vitro skin absorption study was performed using diethyl malonate, no vehicle given.14 Human cadaver split

thickness skin was used in flow through cells. Diethyl malonate (4 µl) was applied to the skin samples. After 24 h, 16% of

the applied dose had penetrated through the skin. The maximum flux rate was reached after 5 h and amounted to 280 µg/h

(350 µg/cm2/h); the mean penetration rate was 99 µg/h (120 µg/cm2/h). Much of the test substance, 45 to 50%, evaporated

from the skin, and 34 to 39% remained on the skin.

Ditridecyl Adipate

Approximately 11% of ditridecyl adipate was absorbed through the skin of rat over 4 days; 5.5-7.4% of the applied dose was found in the tissues, 3.5-4.7% was found in the urine, and 0.4-0.7% was found in the feces after 4 days. Prior dosing with ditridecyl adipate did not significantly affect absorption.

The percutaneous absorption of [14C]ditridecyl adipate was determined using groups of 10 male and 10 female

Sprague-Dawley rats that were untreated or that had previously been exposed to unoccluded dermal applications of 0 or 2000

mg/kg bw ditridecyl adipate, 5 days/wk for 13 wks.86 (This study is described in the section on ‘Subchronic Dermal Toxi-

city’) . A single 58 µl dose of 2000 mg/kg bw [14C]ditridecyl adipate was applied topically (size of test site not specified), and

urine and feces were collected for 4 days. In the previously untreated rats, a total of 11.6 and 10.6% of the [14C] solution was

absorbed by male and female rats, respectively, over 4 days. Approximately 63 and 52% of the absorbed dose (7.4 and 5.5%

of the applied dose, respectively) was found in the tissues of males and females, respectively. A total of 3.5-4.7% of the

applied dose was recovered in the urine and 0.4-0.7% in the feces of previously untreated rats. The values for the animals

previously dosed with 2000 mg/kg bw ditridecyl adipate were not statistically significantly different from the controls. In the

previously dosed animals, a total of 10.8 and 9.1% of the dose was absorbed by males and females, respectively, over the 4

days, with approximately 87 and 81% of the absorbed dose (9.4 and 7.4% of the applied dose, respectively) found in the

tissues of the male and female rats, respectively. A total of 0.7-1.3% of the [14C] was recovered in the urine and 0.4-0.6% in

the feces. Based on the radioactivity recovered in the urine, the bioavailability of ditridecyl adipate was 2-6%, and previous

dosing did not significantly affect absorption.


In vitro, diethylhexyl adipate was readily hydrolyzed to mono-(2-ethylheyxl) adipate( MEHA) or adipic acid in rat liver, pancreas, and small intestine tissue preparations. In animals, diethylhexyl adipate is hydrolyzed to adipic acid and 2-ethylhexanol or MEHA. 2-Ethylhexanol is converted to 2-ethylhexanoic acid, which may form a glucuronide conjugate or may be subjected to ω- and (ω-1)-oxidation and further metabolism. In rats, carbonyl-labeled diethylhexyl adipate rapidly hydrolyzed to adipic acid and MEHA. More than 98% of orally administered diethylhexyl adipate was excreted in 48 h; 21-45% of the radioactivity was expired in carbon dioxide and 34-52% was excreted in the urine. Metabolism studies have shown that excretion in the urine is not as unchanged diethylhexyl adipate; mostly adipic acid is found. In body tissues, the highest levels of radioactivity were found in the liver, kidneys, blood, muscle, and adipose tissue; elimination from the tissues was rapid, with no affinity for a specific organ. In the tissues, diethylhexyl adipate, adipic acid, and/or MEHA were found. When comparing distribution with labeling on the acid versus the alcohol, radioactivity was observed in the ovaries of gravid mice and some fetal tissues following dosing with [carbonyl-14C]diethylhexyl adipate, but none was detected in the ovaries of gravid mice after dosing with [2-ethylhexyl-1-14C]diethylhexyl adipate, and very little radioactivity was seen in fetal tissues. Vehicle affects absorption, but not urinary excretion. In humans dosed orally with diethylhexyl adipate labeled on the ethyl side chains, unconjugated 2-ethylhexanoic acid was the only measurable compound in plasma, and the rate of elimination was rapid. In urine, 2-ethylhexanoic acid was again the principal metabolite, and was probably eliminated in the conjugated form. Peak urinary elimination of all metabolites occurred within 8 h of dosing.


26

In Vitro The in vitro hydrolysis of diethylhexyl adipate (and mono-(2-ethylheyxl) adipate [MEHA]) using tissue preparations

from the liver, pancreas, and small intestine of 2 rats was examined, as were the effects of diethylhexyl adipate on serum and

hepatic enzymatic activities in vitro.87 Diethylhexyl adipate was readily hydrolyzed to MEHA or adipic acid by each tissue

preparation. The formation of adipic acid was rapid and approximately the same for all three tissues, while the formation of

MEHA was rapid only in pancreatic tissue and was negligible in the intestine. The rate of hydrolysis from MEHA to adipic

acid was greater that than from diethylhexyl adipate and the highest activity was found in intestinal tissue. In examining the

effects on serum and hepatic enzymes, only N-demethylase activity was considerably inhibited by diethylhexyl adipate.

In Vivo - Animal The elimination, distribution, and metabolism of diethylhexyl adipate was investigated using male Wistar rats.87 In

these studies, diethylhexyl adipate was labeled at the carbonyl carbon. In elimination studies, 2 rats were dosed by gavage

with 500 mg/kg bw [14C]diethylhexyl adipate (1.26 µCi/rat) as a saturated solution in dimethyl sulfoxide (DMSO), and

respired carbon dioxide, urine, and feces were collected for 2 days. At 24 h after dosing, 86% of the administered dose was

excreted, and at 48 h, more than 98% of the dose was excreted. In one animal, 44.8% of the dose was excreted in expired

carbon dioxide and 33.9% in the urine at the 48 h measurement, while in the other rat, 21.1% and of the dose was excreted in

expired carbon dioxide and 52.2% in the urine. Little (1.4 or 5% of the dose) was excreted in the feces.

In the distribution study, 3 rats per group were given a single dose as described above. The animals were killed at

various intervals, and blood, organ, and tissue samples were collected. Not taking into account the stomach and intestines, the

greatest levels of radioactivity, as a percent of dose administered, were found in the liver, kidney, blood, muscle, and adipose

tissue. These values ranged from 0.34-8.21% at 6 h, with the greatest percentage found in the adipose tissue, and from 0.54-

3.44% at 12 h, with the greatest percentage found in the muscle. In most tissues, the amount of residual radioactivity reached

a peak by 6 h, except for the liver, kidneys, testicles, and muscle, which reached a peak at 12 h. The researchers stated that

the elimination of radioactivity from the tissues and organs was very rapid, and there was no specific organ affinity.

The metabolism of diethylhexyl adipate was examined in rats dosed orally, by gavage, with 100 mg of non-labeled

diethylhexyl adipate as a 5% solution in DMSO. A control group was dosed with vehicle only. The rats were killed 1, 3, or 6

h after dosing. The metabolites were determined using GLC. Diethylhexyl adipate was rapidly hydrolyzed to adipic acid, the

main intermediate metabolite, and MEHA. In the urine, adipic acid was detected at 1 h, and excretion as adipic acid in the

urine reached 20-30% at 6 h. Diethylhexyl adipate and MEHA were not detected in the urine. Adipic acid only also was de-

tected in the blood and the liver, with constant excretion of 0.5-0.7% of the dose in the blood and excretion in the liver in-

creasing with time, with 2-3.3% excreted in the liver at 6 h. In the stomach, diethylhexyl adipate, adipic acid, and MEHA

were found. The concentrations of diethylhexyl adipate declined rapidly, while the levels of adipic acid (9-10%) and MEHA

(6-11.5%) peaked at 3 h. Adipic acid, but not MEHA, was found in the intestine and increased with time, reaching 19% at 6

h.

The absorption, distribution, and elimination of diethylhexyl adipate was examined using radioactive labeling on the

acid [carbonyl-14C] (specific activity 39.5 mCi/mmol) or the alcohol [2-ethylhexyl-1-14C] (44.1 mCi/mmol).40 The research-

ers used both DMSO and commercial corn oil as vehicles for all tests, since the were of the opinion that DMSO is an active

penetrant and carrier of other substances through tissue membranes. It was also their opinion that a fat-soluble substance,

such as diethylhexyl adipate, is more realistically studied dissolved in corn oil. The following groups of animals were dosed

with 84.3 µg (9 µCi) [carbonyl 14C]diethylhexyl adipate or 84.3 µg (10 µCi) [2-ethylhexyl-1-14C]diethylhexyl adipate in both


27

vehicles: 12 male NMRI mice were dosed i.v. and killed at intervals from 5 min to 4 days after dosing; 10 male NMRI mice

were dosed intragastrically (i.g.) and killed at intervals from 20 min to 4 days after dosing; 12 gravid NMRI mice were dosed

i.v. or i.g. on day 17 of gestation and killed at intervals from 20 min to 24 h. Six male rats were dosed i.g. with 843 µg (90

µCi) [carbonyl 14C]diethylhexyl adipate or 843 µg (100 µCi) [2-ethylhexyl-1-14C]diethylhexyl adipate and killed at intervals

from 20 min to 4 h. Whole body autoradiography was used to determine tissue distribution.

Following dosing with [carbonyl-14C]diethylhexyl adipate, distribution was similar in male mice, male rats, and

gravid mice. The amount of radioactivity in the tissues peaked at a later time following i.g. dosing as compared to i.v. dosing.

The presence of radioactivity in the gastrointestinal tract following i.v dosing indicated biliary excretion. Four h following

both i.v. and i.g. dosing, the greatest uptake of radioactivity was found in the liver, bone marrow, brown fat, adrenal cortex,

kidneys, and a few other tissues. At 24 h after i.g. dosing, significant levels of radioactivity remained in several tissues,

including the liver, of both rats and mice. In gravid mice, a “remarkable strong uptake” of radioactivity in the corpora lutea of

the ovary was observed at all time intervals with both i.v. and i.g. dosing, and some radioactivity was found in the fetal

intestine, liver, and bone marrow.

Similar distribution patterns were seen following dosing with [2-ethylhexyl-1-14C]diethylhexyl adipate as were seen

with [carbonyl-14C]diethylhexyl adipate. Following i.g. dosing, the appearance of radioactivity was lessened and not as great

as it was with i.v. dosing. Very high radioactivity levels were seen in the liver and kidney at 5 min-1 h after i.v. dosing and at

20 min-4 h after i.g. dosing. The radioactivity in the liver was still high at 24 h after i.g. dosing in mice and rats. Radioacti-

vity was also seen in the intestinal contents at 1-4 h after i.v. dosing, again indicating biliary excretion. At longer intervals

after i.v. injection, 4 h-4 days, radioactivity was detected in the bronchi of mice. While radioactivity was observed in the

ovaries of gravid mice and some fetal tissues following dosing with [carbonyl-14C]diethylhexyl adipate, none was detected in

the ovaries of gravid mice after dosing with [2-ethylhexyl-1-14C]diethylhexyl adipate, and very little radioactivity was seen in

some fetal tissues.

The effect of vehicle on the absorption and biliary and urinary excretion of diethylhexyl adipate was also examined

using rats in a gavage study with [14C]diethylhexyl adipate. Radioactivity was measured every 30 min for 7.5 h. The times

and extent of absorption were different for all four preparations of [14C]diethylhexyl adipate. Radioactivity levels in the blood

increased faster and were greater with DMSO as the vehicle, as compared to corn oil. The highest blood radioactivity levels

were found with [carbonyl-14C]diethylhexyl adipate in DMSO. Biliary excretion of [14C]diethylhexyl adipate was greatly

affected by vehicle; with DMSO, 41% of the dose was detected in the bile, while only 10% of the dose was found with the

corn oil vehicle. This difference was not seen with [carbonyl-14C]diethylhexyl adipate. Finally, vehicle did not have much

influence on urinary excretion. However, unlike the results reported by the previous researchers, little radioactivity was

excreted in the urine. The researchers hypothesized that since the study duration was only 7.5 h, urinary excretion may not

have been complete.

The metabolism of diethylhexyl adipate was examined in vivo using male Wistar rats and compared to in vitro

metabolism using hepatocytes.88 In vivo, rats were dosed with 0.665 or 1.5 g/kg diethylhexyl adipate in corn oil by gavage for

5 days, and the controls were given vehicle only. Urine was collected daily. Diethylhexyl adipate was not recovered in the

urine after 24 h. Adipic acid was the main metabolite of diethylhexyl adipate. In vitro, the first hydrolysis of diethylhexyl

adipate appears to be a rate-limiting step. In vivo, it was thought that this hydrolysis probably occurs in the gastrointestinal

tract. Metabolic pathways (ω and ω-1oxidations, glucuronidation) seemed to prove that transformations of diethylhexyl

adipate are localized mainly in the liver.


28

Oral administration of diethylhexyl adipate to cynomolgus monkeys results in rapid elimination, with 47-57% of the

dose excreted in the urine.17 Unchanged diethylhexyl adipate is absorbed from the gastrointestinal tract, and the glucuronide

of MEHA and traces of unchanged diethylhexyl adipate were found in the urine. (Details were not provided).

In Vivo - Human The pharmacokinetics of [2H10]diethylhexyl adipate, labeled on the ethyl side-chains, were examined using 6 male

subjects.89 A dose of 46 mg [2H10]diethylhexyl adipate in corn oil, for a total volume of 0.5 cm3, was administered orally in a

gelatin capsule. Blood samples were taken for up to 31 h after dosing, and urine samples were taken at intervals for up to 96

h after dosing. In the plasma, unconjugated [2H5]2-ethylhexanoic acid was the only measurable diethylhexyl adipate-related

compound. This compound appeared rapidly in the plasma, and the peak concentrations (1.6 ±0.5 µg/cm3) occurred between

1 and 2 h. [2H5]2-Ethylhexanol was detected, but it was below the limit of quantification. The rate of metabolite formation

was calculated, since there was no evidence of diethylhexyl adipate absorption, as 1.63 ± 1.19 hr-1. The rate of elimination

from the plasma was also rapid and estimated to be 0.42 ± 0.15 h-1., which corresponded to an elimination half-life of 1.65 h.

Although there were inter-individual differences in the rate and extent of [2H5]2-ethylhexanoic acid formation, it was below

the limit of detection in all subjects by 31 h.

In the urine, [2H5]2-ethylhexanoic acid was again the principal metabolite, and it was probably eliminated as a

conjugated product. This conjugated form, most likely the glucuronide, accounted for up to 99% of the total [2H5]2-ethyl-

hexanoic acid measured. Conjugation of the other urinary metabolites was minimal. Peak urinary elimination of the

measured metabolites occurred within 8 h of dosing, and no metabolites were detected in the urine after 36 h. The rates of

elimination were similar for all metabolites, with a mean elimination half-life of 1.5 h. The measured urinary metabolites

accounted for 12.1% of the dose, with the majority being eliminated in 24 h. Fecal analysis determined that a minor portion

of the dose was present as diethylhexyl adipate (0.43%) and [2H5]MEHA (0.27%). The researchers noted that recovery of the

administered dose was incomplete and hypothesized that it was most probably due to further systemic metabolism.

Diethylhexyl Sebacate

Diethylhexyl sebacate is not readily absorbed through the skin of guinea pigs (no further details were provided).1 It

was noted that the metabolism of diethylhexyl sebacate in rodents and humans may follow partially common pathways,

Peroxisome Proliferation

Diethylhexyl adipate is a peroxisome proliferator requiring extensive phase I metabolism to produce the proximate

peroxisome proliferator, which in both mice and rats, appears to be 2-ethylhexanoic acid.90,91 Diethylhexyl adipate has been

studied because it is structurally related to diethylhexyl phthalate, although diethylhexyl adipate is not as potent a proliferator

as diethylhexyl phthalate.92,93

Peroxisome proliferation causes an increase in liver weights and can induce hepatocarcinogenicity in rats and mice.

Peroxisome proliferation is not believed to pose the risk of inducing hepatocarcinogenesis in humans, as a species difference

in response to peroxisome proliferators exists.94 In vitro and in vivo studies examining the induction of peroxisome

proliferation by diethylhexyl adipate and diethylhexyl sebacate are summarized in Table 8.59,90-93,95,96 While proliferation was

observed, these ingredients have much weaker activity than diethylhexyl phthalate and ciprofibrate, which are very effective

peroxisome proliferators.

Humans do not react to peroxisome proliferators in the manner that rodents do. There is no effect on organelle

proliferation and induction of peroxisomal and microsomal fatty acid-oxidizing enzymes in species other than rats and mice,

including humans. Consequently, these results have no relevance to humans.


29


In male rats given 2% diethylhexyl adipate in the feed for 3 wks, hepatic peroxisome proliferation, an increase in liver size, and an increase in two hepatic activities of peroxisome-associated enzymes, catalase and carnitine acetyl transferase, were observed. It was postulated that a metabolite, 2-ethylhexyl alcohol, may be responsible for the induction of hepatic peroxisome proliferation.


DNA Binding/DNA Synthesis

Diethylhexyl adipate did not bind covalently to hepatic DNA in mice. It did stimulate DNA synthesis in livers of rats. In another study, a statistically significant increase in 8-OH-dG occurred in the liver DNA, but not the kidney DNA, at wk 1 and 2. The IARC remarked that the weight of evidence for diethylhexyl adipate demonstrated that rodent peroxisome proliferators do not act as direct DNA-damaging agents in rodents.


The potential of diethylhexyl adipate to bind to liver DNA of female NMRI mice was evaluated by administering a

solution of 119 mg diethylhexyl adipate/ml with 3.85 mCi/ml of [14C]diethylhexyl adipate (labelled at C1 of the alcohol

moiety) and 27.7 mCi/ml of [3H]diethylhexyl adipate (tritiated at positions 2 and 3 of the alcohol moiety) in olive oil.97 The

animals were dosed by gavage, and the livers were excised 16 h after dosing. Some animals were pretreated with 10 g/kg of

unlabeled dietary diethylhexyl adipate for 4 wks. Diethylhexyl adipate did not covalently bind to hepatic DNA in mice. Pre-

treatment with diethylhexyl adipate caused an increase in liver weight, but no increase in DNA binding. The researchers

stated that tumorigenicity of diethylhexyl adipate must be due to an activity other than DNA binding.

The ability of diethylhexyl adipate to stimulate liver DNA synthesis in male F344 rats was investigated using radio-

labeled thymidine.98 Contrary to expected results, diethylhexyl adipate did stimulate DNA synthesis. The stimulation factor,

which is indicated by the ratio of the thymidine incorporation in treated animals compared to controls, was 10.5 and the

doubling dose, which is the dose that produced a doubling of the control level DNA synthesis, was 0.7 mmol/kg.

The effect of dosing with diethylhexyl adipate on 8-hydroxydeoxyguanosine (8-OH-dG) in liver and kidney DNA of

rats was examined.99 Groups of 10 male F344 rats were fed a diet containing 0 or 2.5 diethylhexyl adipate. Five animals per

group were killed after 1 wk, and the other 5 after 2 wks of dosing. Relative liver to body weights were statistically signifi-

cantly increased after 1 and 2 weeks of dosing, and the relative kidney to body weights were statistically significantly

increased only after 2 wks. A statistically significant increase in 8-OH-dG was increased in the liver DNA, but not the kidney

DNA, at wk 1 and 2.

The IARC remarked that the weight of evidence for diethylhexyl adipate, and other rodent peroxisome proliferators

in general, demonstrated that rodent peroxisome proliferators do not act as direct DNA-damaging agents.17

Hepatic Lipid Metabolism


Dietary administration of diethylhexyl adipate affects hepatic lipid metabolism.17 Hepatic fatty acid-binding protein

and microsomal stearoyl-CoA desaturation were increased in Wistar rats fed 2% diethylhexyl adipate for 7 days.100,101 When

fed to rats for 14 days, an increase in hepatic phospholipid levels and a decrease in phosphatidylcholine:phosphatidylethanol-

amine ratio was reported.102 In male NZB mice fed 2% diethylhexyl adipate for 5 days, an induction of fatty acid translocase,

fatty acid transporter protein, and fatty acid binding protein in the liver was reported.103


30

Cellular Effects

Dibutyl Adipate

Dibutyl adipate was tested for cytotoxicity in the metabolic inhibition test. A dilution series of dibutyl adipate was suspended in HeLa cells. Dibutyl adipate had no acute toxicity to the cells, which was attributed to its insolubility in water.

From the Amended Final Report on Dibutyl Adipate5

ANIMAL TOXICOLOGY

Acute Toxicity

The oral and dermal LD50 values are greater than 2 g/kg. No mortality occurred in rats exposed to concentrated vapors of diethyl malonate diethyl succinate, dibutyl adipate, or diethylhexyl adipate for 8 h. Some deaths, possibly due to thermal decomposition were seen in rats and rabbits exposed to 940 mg/m3 for 7 h. In a 4-hr inhalation toxicity study, a mixture of dimethyl glutarate, dimethyl succinate, and dimethyl adipate, the anterior and posterior nasal passageways were affected

Acute toxicity data on esters of dicarboxylic acids are presented in Table 9.1,14,41,86,104-116 Data from the original

safety assessments on dibutyl, diisopropyl and diethylhexyl adipate are included in italics.2,5 The acute toxicity of esterase

metabolites are also summarized in this table.117,118

Short-Term Oral Toxicity

Oral administration of ≤1000 mg/kg bw dibutyl adipate for 28 days did not produce toxic effects in rats. In short-term oral dosing with diethylhexyl adipate, decreased weight gain was reported for rats and mice. The NOELs for rats and mice were 2 and 0.63%, respectively, in feed; 5/5 female mice fed 10% dibutyl adipate in feed died. In 2- and 4-wk studies of diethylhexyl adipate, the oral NOAEL for ovarian toxicity was 200 mg/kg bw in rats; an increase in atresia of the large follicle and a decrease in currently formed corpora lutea were seen in females dosed with 1000 and 2000 mg/kg bw diethylhexyl adipate.

Dibutyl Adipate

Male and female Crj:CD(SD) rats, number per group not specified, were dosed orally, by gavage, with 0, 20, 140, or

1000 mg/kg bw dibutyl adipate in olive oil daily for 28 days.104 No clinical, hematological, or microscopic test-article related

changes were observed.


In a 14-day dietary study, groups of 5 male rats and mice were given ≤50,000 ppm and groups of 5 female rats and mice were given ≤100,000 ppm diethylhexyl adipate. Male rats and mice fed 50,000 ppm and female rats and mice fed ≥25,000 ppm had decreased weight gains or weight loss. (It is not specified whether the results were statistically significant.) One female rat and all female mice of the 100,000 ppm group died.


In the 14-day study described in the section on “Peroxisome Proliferation” in which 5 male and 5 female Wistar and

F344 rats and Swiss and B6C3F1 mice were dosed with 0-2.5 g/kg diethylhexyl adipate in corn oil for 14 days, diethylhexyl

adipate was toxic to female B6C3F1 mice, causing mortality, at a dose level of 2.5 g/kg.91 The toxicity of two metabolites of

diethylhexyl adipate, 2-ethylhexanol and 2-ethylhexanoic acid, was also examined using Wistar rats and Swiss mice. 2-Ethyl-

hexanol was toxic to male and female rats, with mortality reported at doses >1.05 g/kg in male and female rats. 2-Ethylhexa-

noic acid was toxic to female rats, with mortality reported at doses ≥1.9 g/kg; mortality was not reported for male rats. These

effects were not reported in mice.

In a 1 and 4-wk dietary study described in the section on “Peroxisome Proliferation” in which groups of 5-8 rats and

mice were fed diets containing 0-4.0% and 0-2.5% diethylhexyl adipate, respectively, feed consumption by rats was decreased

in the 4.0% group at 1 wk and in the 2.5 and 4.0% dose groups at 4 wks.95 Body weights were significantly decreased in these

groups. Feed consumption by mice was not affected, but a significant decrease in body weights was seen in the 1.2 and 2.5%


31

dose groups at 4 wks.

Toxicity was evaluated in a study in which groups of 10 female Crl:CD(SD) rats were dosed, by gavage, with 5

ml/kg of 0, 200, 1000, or 2000 mg/kg bw diethylhexyl adipate in corn oil for 2 or 4 wks.119 All animals survived until study

termination. In the 2-wk study, no statistically significant findings were observed for the animals dosed with 200 mg/kg bw,

and the only statistically significant finding in the 1000 mg/kg bw dose group was an increase in relative liver to body weight.

In the 2000 mg/kg bw dose group, there was staining around the perineum, statistically significant increases in relative liver

and kidney to body weights, and a statistically significant decrease in the relative weight of the left ovary. Microscopically,

abnormal findings were reported for both the ovary and kidney. In the ovary, an increase in atresia of the large follicle and a

decrease in currently formed corpora lutea were seen in animals dosed with 1000 and 2000 mg/kg bw, and in the 2000 mg/kg

bw group, an increase in follicular cysts was observed. In the kidney, an eosinophilic change of the proximal tubule was

observed for the 2000 mg/kg bw dose group. The NOAEL was 200 mg/kg bw.

In the rats dosed for 4 wks, similar observations were made. There was staining around the perineum of animals

dosed with 1000 and 2000 mg/kg bw diethylhexyl adipate, and final body weights of animals dosed with 2000 mg/kg bw were

statistically significantly decreased. The relative kidney to body weights were statistically significantly increased in animals

at all dose levels, and liver weights were statistically significantly increased in animals of the 1000 and 2000 mg/kg bw dose

groups. The mean estrous cycle length was statistically significantly decreased in the 200 mg/kg bw dose group, but this was

not considered treatment-related since a dose-response was not seen. The same microscopic abnormalities reported in the 2

wk study were seen in the ovaries and kidneys of the animals dosed with 1000 and 2000 mg/kg bw in the 4-wk study. As in

the 2-wk study, the NOAEL for ovarian toxicity was 200 mg/kg bw.

Short-Term Dermal Toxicity

In a short-term dermal study in which 10 rabbits were dosed dermally with 0.5 or 1.0 ml/kg of a 20% dispersion of dibutyl adipate for 6 wks, there was a significant decrease in body weights in the high dose group, and renal lesions in one animal of each group. There were no signs of toxicity in guinea pigs in an immersion study with 20.75% diisopropyl adipate, diluted to an actual concentration of 0.10% adipate. Dermal administration of diethylhexyl adipate to rabbits for 2 wks resulted in slight to moderate erythema at the test site, but toxic effects were not reported for most of the animals.

Dibutyl Adipate

Groups of 10 rabbits were dosed dermally with 0.5 or 1.0 ml/kg/day of a 20% dispersion of dibutyl adipate, 5x/wk for 6 wks. A significant reduction in body weight gain was seen for animals of the 1.0 ml/kg/day group, and renal lesions were seen in one animal of each group.


Diisopropyl Adipate

An immersion study was performed using guinea pigs in which a product containing 20.75% diisopropyl adipate was diluted, giving an actual adipate concentration of 0.10%. The animals were immersed 4 h/day for 3 days. There were no signs of systemic toxicity, and the degree of dermal irritation was considered minimal.



Diethylhexyl adipate, 410 or 2060 mg/kg bw, was applied to the shaved abdomen of male rabbits, 4 per group, 5

days per wk for 2 wks.115 Mineral oil was applied in the same manner to a group of 4 rabbits as a negative control. A collar

was used to restrict ingestion. One animal in the 410 mg/kg bw group died during wk 2 of the study. All other animals in this

group appeared normal. Slight to moderate erythema was observed at the test site. No animals of the 2060 mg/kg bw group


32

died, but 3 of the 4 did not gain weight, and they had labored breathing and were lethargic during wk 2. Moderate erythema

was observed in this group. Microscopically, one animal of the 2060 mg/kg bw group had altered cytology of the liver

parenchymal cells. No other microscopic lesions were noted.

Short-Term Inhalation Toxicity


No deaths occurred when 4 rats, 2 guinea pigs, 2 rabbits and 1 cat were exposed to 400 mg diethylhexyl sebacate/m3,

7 hrs/day, for 10 days.1 Details were not provided.

Subchronic Oral Toxicity

In a 90-day oral toxicity study using rats, the NOEL for diethyl malonate was 1000 mg/kg bw/day. Dietary administration of ≤2.5% di-C7-9 branched and linear alkyl esters of adipic acid (approx. 1500 and 1900 mg/kg bw/day for males and females, respectively) for 90 days did not result in systemic toxicity. The NOAELS for male and female rats were 1500 and 1950 mg/kg bw/day, respectively. Subchronic oral administration of diethylhexyl adipate to rats caused significant decreases in body weight gains and increases in liver and kidney weights. The dietary NOEL for rats in a 90-day study was 610 mg/kg bw. A decrease in body weights was seen in mice fed a diet with 1.2 and 2.5% diethylhexyl adipate. For diisononyl adipate, dietary administration of up to 500 mg/kg bw for 13 wks, a statistically significant increase in relative kidney to body weights was reported, but there were no toxicological findings. With dogs, 3.0% dietary diisononyl adipate resulted in a decrease in body weights, testes weight, and feed consumption, increased liver weight, elevated enzyme levels, liver and kidney discoloration, and microscopic changes in the liver, testes, spleen, and kidneys.

Diethyl Malonate

Groups of 10-16 male and female CD rats were fed diets containing either 0, 36 (males) or 41 mg/kg bw/day

(females) diethyl malonate for 90 days.14 No treatment related effects were observed, and the NOEL was 1000 mg/kg

bw/day.

Di-C7-9 Branched and Linear Alkyl Esters of Adipic Acid

Groups of 15 male and 15 female Sprague-Dawley rats were fed a diet containing 0, 0.1, 0.5, or 2.5% di-C7-9

branched and linear alkyl esters of adipic acid for 90 days, corresponding to approximately 1500 mg/kg bw/day for high dose

males and 1900 mg/kg bw/day for high dose females.86 All rats were killed for necropsy at study termination. No systemic

toxicity was reported. Small, but significant, increases in absolute and relative kidney to body weights reported for females of

the 2.5% dose group were not considered treatment-related. The NOAELs for male and female rats were 1500 and 1950

mg/kg bw/day, respectively.


In a 13-wk dietary study, groups of 10 rats and 10 mice were fed ≤25,000 ppm diethylhexyl adipate. With the exception of decreased weight gain for some of the groups, no compound-related toxicologic effects were observed.


In a 90-day dietary study, groups of 10 rats per group were fed 0-4740 mg/kg bw diethylhexyl adipate for 90 days.115

Mortality occurred in the 4740 mg/kg bw group, but the number of deaths was not specified. Decreased growth and feed con-

sumption was reported for animals fed 2920 mg/kg bw. Changes in kidney and liver weights were noted, but no details were

given. The NOEL was 610 mg/kg bw, and the LOEL was 2920 mg/kg bw diethylhexyl adipate.

Groups of 15 male and 15 female Sprague Dawley rats were fed 0 or 2.5% diethylhexyl adipate for 90 days.86 At

study termination, all animals were killed for necropsy. Body weight gains were statistically significantly decreased for

treated males and females, and relative kidney and liver to body weights were statistically significantly increased for treated

females, when compared to controls.

In a 13-wk dietary study described in the section on “Peroxisome Proliferation” in which groups of 5-8 rats and

mice were fed diets containing 0-4.0% and 0-2.5% diethylhexyl adipate, feed consumption by rats was decreased in the 2.5


33

and 4.0% dose groups, and body weights were significantly reduced in these groups.95 Feed consumption by mice was not

affected, but a significant decrease in body weights was seen in the 1.2 and 2.5% dose groups.

Diisononyl Adipate

Groups of 10 male and 10 female rats were fed 0, 50, 150, or 500 mg/kg bw diisononyl adipate for 13 wks.86 A

statistically significant increase in relative kidney to body weights was reported for males and females given 500 mg/kg bw,

but absolute kidney weights were not affected and no significant microscopic effects were seen. Microscopic changes in any

of the organs, including the testes and epididymis of males and ovaries of females, were not observed. There were not

significant toxicological findings, and the NOAEL was 500 mg/kg bw/day.

In another 13-wk study, groups of 4 male and 4 female beagle dogs were fed 0, 0.3, 1.0, or 3.0% diisononyl adipate;

the high dose was increased to 6% during wks 9-13. No significant findings were reported for the 0.3 or 1.0% groups. In the

high dose group, decreased body weight, testes weight, and feed consumption, increased liver weight, elevated enzyme levels,

liver and kidney discoloration, and microscopic changes in the liver, testes, spleen, and kidneys were reported. The dietary

NOAEL for diisononyl adipate was 1.0%.

Subchronic Dermal Toxicity

No adverse effects were reported with whole-body application of an 6.25% emulsion of dibutyl adipate to dogs2x/wk for 3 mos. Unoccluded dermal application of up to 2000 mg/kg bw ditridecyl adipate for 13 wks to rats produced slight erythema, but no systemic toxicity.

Dibutyl Adipate

No adverse effects were reported in a study using 4 dogs in which entire-body applications of an emulsion containing 6.25% dibutyl adipate were made 2x/wk for 3 mos.


Ditridecyl Adipate

Ditridecyl adipate, 0, 800, or 2000 mg/kg bw, was applied to the backs of groups of 10 male and 10 female Sprague-

Dawley rats, 5 days/wk for 13 wks.86 The test sites were not occluded, but the animals wore Elizabethan collars. Slight

erythema and flaking of the skin was observed in the treated groups, with hyperplasia of the sebaceous glands in the dermis,

but otherwise no significant differences were observed between test and control animals. Differences in relative organ to

body weights were not statistically significant, and ditridecyl adipate did not appear to cause systemic toxicity.

Subchronic Inhalation Toxicity


Groups of 12 F344 rats, gender not specified, were exposed 4 h/day, 5 days/wk, to 25 or 250 mg/m3 diethylhexyl

sebacate for ≤13 wks.86 No adverse systemic or lung effects were observed.

Chronic Oral Toxicity

In a 6-mos study in which rats were dosed intragastrically with ≤2.0 g/kg diethylhexyl adipate, hepatic detoxification appeared depressed at the beginning of the study, while in a 10-mos study, a decrease in central nervous system excitability was noted. Dietary administration of ≤1.25% dibutyl sebacate for 1 yr or ≤6.25% for 2 yrs did not have an effect on growth.


Intragastric doses of ≤2.0 g/kg diethylhexyl adipate to rats (number not stated) for 6 mos produced no enzymatic changes, but levels of sulphydryl compounds in the blood were increased. Hepatic detoxification appeared depressed at the onset of the study, but it was accelerated after 6 mos. Administration of 0.1 g/kg for 10 mos decreased central nervous system excitability.



34

Dibutyl Sebacate

Groups of 5 male and 5 female Sprague-Dawley rats were fed a diet containing 0, 0.01, 0.05, 0.25, or 1.25% dibutyl

sebacate for 1 yr.114 Necropsies were performed whenever rats exhibited significant weight losses or other evidences of

severe concurrent infection. Dibutyl sebacate had no effect on growth or well-being.

The researches then fed groups of 16 male Sprague Dawley rats a diet containing 0.01, 0.05, 0.25, 1.25, or 6.25%

dibutyl sebacate for 2 yrs.114 Two control groups were given untreated feed. Necropsies were performed on 3 rats from each

group after 1yr, and the experiment was terminated at the end of the 2-year feeding period. Interim, animals were killed

whenever they became moribund. In such instances the rats usually had incapacitating tumors or severe intercurrent infec-

tions. Dibutyl sebacate did not adversely affect growth or survival, and it did not produce significant hematological changes

in peripheral blood. As the rats increased in age, slight changes in distribution of leukocytes were found, but these trends

occurred in both the control and treatment groups.

Ocular Irritation

Ocular irritation appeared to lessen in severity as chain length of the dicarboxylic acid esters increased. Diethyl malonate was slightly to moderately irritating to rabbit eyes. Dibutyl, diisopropyl, and diethylhexyl adipate were non- or minimal ocular irritants. Diisopropyl sebacate was minimally irritating, while diethylhexyl sebacate was non-irritating to rabbit eyes. Dioctyldodecyl and diisocetyl dodecanedioate were not irritating to rabbit eyes.

Ocular irritation data on esters of dicarboxylic acids are presented in Table 10. Data from the original safety assess-

ments on dibutyl, diisopropyl and diethylhexyl adipate are included in italics. The available ocular irritation data on esterase

metabolites are also summarized in this table.

Diethyl Malonate

The ocular irritation potential of diethyl malonate was evaluated using rabbits, number and gender not specified.14

A volume of 0.1 ml was instilled into the conjunctival sac of one eye, which was not rinsed, and the contralateral eye was

untreated and served as the negative control. Diethyl malonate produced slight to moderate irritation.

Dimethyl Malonate

In a similar study as described above, undiluted dimethyl malonate produced slight to moderate irritation in rabbit

eyes.14 All signs of irritation were cleared by day 8.

Dibutyl Adipate

Undiluted dibutyl adipate was minimally irritating to the eyes of rabbits, and 0.1% in olive oil was non-irritating.


Diisopropyl Adipate

The ocular irritation potential of 2 lots of undiluted diisopropyl adipate was evaluated using rabbits. One caused negligible irritation, while the other was non-irritating. A formulation containing 0.7% diisopropyl adipate produced some corneal stippling in rabbit eyes, while a formulation containing 5.0% and one containing 20.75% were non-irritating to rabbit eyes.


The ocular irritation of undiluted diisopropyl adipate was evaluated using 3 albino rabbits.112 A volume of 0.1 ml

was instilled into the conjunctival sac of one eye, which was not rinsed. The contralateral eye was untreated and served as the

negative control. Diisopropyl adipate was not irritating.


35


Undiluted diethylhexyl adipate was non-irritating to rabbit eyes and a formulation containing 0.0175 was, at most, a mild transient irritant.



A primary ocular irritation study was performed using 6 New Zealand white rabbits to determine the ocular irritation

potential of diisopropyl sebacate.120 A volume o f 0.1 ml was applied to one eye of each animal, which was not rinsed, and

the contralateral eye of each animal served as the control. The average Draize scores were 2.0 at 24 and 48 h, 0.3 at 72 h, and

0.0 at 4 days. Diisopropyl sebacate was a minimal ocular irritant.


The ocular irritation of a cream containing 1.2% diethylhexyl sebacate was evaluated using the in vitro EpiOcular

MTT viability assay .121 The tissue samples were exposed to undiluted test material for 64 min, 256 min, or 1200 min.

Following treatment, the viability of those tissues were calculated. The ET50 (time for tissue viability to be reduced by 50%)

was 484.9 min, and diethylhexyl sebacate was considered to be non-irritating.

Dioctyldodecyl Dodecanedioate

The primary eye irritation of dioctyldodecyl dodecanedioate was evaluated using 6 albino rabbits.122 A volume of

0.1 ml was applied to one eye of each animal, which was not rinsed. and the contralateral eye served as a negative control.

They eyes were evaluated at 24, 48, and 72 h. At 24 h, the maximum mean total score (MMTS) was 0.00, and dioctyldodecyl

dodecanedioate was considered not irritating.

Diisocetyl Dodecanedioate

The primary eye irritation of diisocetyl dodecanedioate was evaluated using the procedure described above.123 The

MMTS was 0.00, and diisocetyl dodecanedioate was considered not irritating to the eyes of rabbits.

Dermal Irritation

The esters of dicarboxylic acids were mostly non or mildly irritating to rabbits. Some minimal irritation was seen with diisopropyl adipate, undiluted or at 5-20.75% in formulation, and moderate erythema was reported with undiluted dibutyl adipate.

Dermal irritation and sensitization data on esters of dicarboxylic acids are presented in Table 11. Data from the

original safety assessments on dibutyl, diisopropyl and diethylhexyl adipate are included in italics. The available dermal

irritation and sensitization data on esterase metabolites are also summarized in this table.

Diethyl Malonate

The dermal irritation potential of diethyl malonate was evaluated using a 24 h occlusive application.14 Diethyl

malonate was slightly irritating to rabbit skin.

Dimethyl Malonate Dimethyl malonate was applied undiluted to rabbit skin for 4 h under a semi-occlusive patch.14 Slight erythema was

observed only at 30-60 min after patch removal, and dimethyl malonate was considered non-irritating to rabbit skin.

Dibutyl Adipate

Application of undiluted butyl adipate to rabbit skin resulted in a primary irritation score of 2/8. Undiluted dibutyl adipate caused moderate erythema in rabbits following repeated dermal exposure. However, material impregnated with dibutyl adipate was not irritating to the skin of rabbits. Application of dibutyl adipate at 10% in acetone produced no observable adverse effect when applied to rabbit ears, and no dermal reaction was observed following twice daily application for 14 days to the backs of hairless mice. Two perfume formulations containing 1.1% diisopropyl adipate


36

were not primary dermal irritants using rabbits.


Diisopropyl Adipate

Draize tests of undiluted diisopropyl adipate resulted in, at most, mild irritation of rabbit skin. In Draize tests with formulations containing 5.0% or 20.75% diisopropyl adipate, minimal irritation was reported with both formulations.



Undiluted diethylhexyl adipate was a very mild irritant when applied under occlusion to intact and abraded rabbit skin. A formulation containing 0.175% diethylhexyl adipate had an irritation index of 1.6/4.


Diisodecyl Adipate

The dermal irritation potential of diisodecyl adipate was determined using 3 albino rabbits.110 Undiluted test

material was applied to the skin for 4 h under a semi-occlusive patch. The erythema scores were 0-1 during 1-72 h, and the

edema scores were 0. Diisodecyl adipate was considered non-irritating to rabbit skin.

Dioctyldodecyl Adipate

The dermal irritation of dioctyldodecyl adipate was evaluated using the same procedure.111 The erythema scores

were 0-2 during 1-72 h, and the edema scores were 0-1. Dioctyldodecyl adipate was considered non-irritating to rabbit skin.

Diisocetyl Adipate

The dermal irritation of diisocetyl adipate was evaluated using the same procedure.109 The erythema scores were 0-2

during 1-72 h, and the edema scores were 0-1. Diisocetyl adipate was considered non-irritating to rabbit skin.

Diethyl Sebacate

Undiluted diethyl sebacate and 30% diethyl sebacate in ethanol were tested on 8 male Japanese White strain rabbits

(gender not specified).124 The flank of the animals was clipped free of hair 1 day prior to application of test substance. The

skin of 4 animals was abraded. The test substance, 0.3 ml, was applied occlusively to the back of all animals for 24 h. The

skin reactions were evaluated at 24 h and 72 h. The primary irritation score was 0.0 (none to weak irritant) in undiluted

diethyl sebacate and 0.3 (none to weak irritant) in 30% diethyl sebacate. These results suggest that 100% diethyl sebacate has

no primary skin irritation under these test conditions.


A primary dermal irritation study on diisopropyl sebacate was performed using 6 New Zealand white rabbits.120 A

dermal application of 0.5 ml of undiluted test material was applied to an abraded and an intact site on each animal. The test

sites were occluded for 24 h and observed individually for erythema, edema, and other effects 24 and 72 h after application.

Mean scores from the 24 and 72 h reading were averaged to give a primary irritation index (PII) of 2.88. Diisopropyl sebacate

was not considered a primary dermal irritant.

The dermal irritation potential of diisopropyl sebacate was determined using 3 albino rabbits.125 Undiluted test

material was applied to the skin for 4 h under a semi-occlusive patch. The erythema scores were 1 during 1-72 h, and the

edema scores were 0-1. Diisopropyl sebacate was considered non-irritating to rabbit skin.


37


The dermal irritation potential of diethylhexyl sebacate was evaluated using the same procedure.108 The erythema

scores were 1 during 1-72 h, and the edema scores were 0. Diethylhexyl sebacate was considered non-irritating to rabbit skin.

Patch tests with diethylhexyl sebacate (neat; 48-hr occluded) did not irritate the skin of 2-4 rabbits.1 It was also

reported that diethylhexyl sebacate was non-irritating to the skin of guinea pigs. No further study details were provided.

Dermal Sensitization

Dimethyl malonate, dibutyl and diethylhexyl adipate, diethylhexyl sebacate, and dioctyldodecyl dodecanedioate were not sensitizers in guinea pigs or rabbits.

Dimethyl Malonate

Dimethyl malonate was not a sensitizer in a Buehler guinea pig sensitization test according to OECD TG 406.14

Dibutyl Adipate

Dibutyl adipate was not a dermal sensitizer in guinea pigs when tested at 25% in a maximization test.



Diethylhexyl adipate, 0.1%, was not a sensitizer in a maximization study using guinea pigs.



A limited attempt was made to sensitize a group of 2-4 rabbits by applying diethylhexyl sebacate using occlusive

patches.1 No reactions were seen in an occlusive challenge with the undiluted test article 2 weeks later. Details were not

provided.


A maximization test was performed to evaluate the sensitization potential of dioctyldodecyl dodecanedioate.126 Ten

female guinea pigs were used. The dose used at intradermal injection was 0.1 ml, and 0.5 ml was used for the topical

challenge. Slight erythema was observed at induction, but a sensitization reaction was not observed.

Phototoxicity

Diisopropyl Adipate

Two perfume formulations containing 1.1% diisopropyl adipate were not phototoxic in rabbits.


Mucous Membrane Irritation


A product containing 0.175% diethylhexyl adipate did not produce mucous membrane irritation in rabbits.


REPRODUCTIVE AND DEVELOPMENTAL TOXICITY

Oral administration of up to 1000 mg/kg bw dimethyl malonate to Wistar rats did not have an effect on fertility, and no developmental toxicity was reported. The NOAEL was 300 mg/kg bw for repeated dose and maternal toxicity and 1000 mg/kg bw for fertility and developmental toxicity. Oral administration of up to 100 mg/kg bw dibutyl adipate to Sprague-Dawley rats did not cause any reproductive effects, and the NOEL for parental and offspring toxicity was 300 mg/kg bw/day and for reproductive toxicity was 100 mg/kg bw/day. Oral administration of ≤7000 mg/kg bw di-C7-9 branched and linear


38

alkyl esters of adipic acid to Sprague-Dawley rats did not result in developmental toxicity. Dietary administration of up to 1.2% diethylhexyl adipate did not affect fertility when fed to rats prior to mating. Fetal weight, total litter weight, and litter size were reduced with 1.2% diethylhexyl adipate. In a study in which gravid rats were fed the same doses during gestation, no significant effects on fetal weight or litter size were reported. An increased incidence of minor skeletal abnormalities was attributed to fetotoxicity. In a study in which diethylhexyl adipate was given orally to rats from day 7 of gestation until post-natal day 17, antiandrogenic effects were not observed, although some increase in post-natal death was observed. Admini-stration of up to 2000 mg/kg bw diethylhexyl adipate prior to dosing and through day 7 of gestation did have an effect on the mean estrous cycle length at a dose of 1000 and 2000 mg/kg bw, and did appear to disturb ovulation. Significant decreases were also seen in implantation rate and number of live embryos, as well as an increase in pre-implantation loss. Diethylhexyl adipate did not produce testicular toxic effects in male F344 rats when fed at up to 25,000 ppm in the diet for 4 wks. Dietary administration of 6.25% dibutyl sebacate to male and female Sprague Dawley rats for 10 wks prior to mating had no adverse effects on fertility, litter size, or survival of offspring. Diethylhexyl sebacate, 200 ppm in the diet, did not produce reproductive or developmental effects in rats.

Dermal application of 2000 mg/kg bw ditridecyl adipate did not have an effect on sperm morphology. Some visceral anomalies were reported. The NOAELs for maternal toxicity and developmental and reproductive effects were 2000 and 800 mg/kg bw/day, respectively.

Dimethyl, diethyl, dipropyl, dibutyl, diisobutyl, and diethylhexyl adipate were evaluated for fetotoxic and teratogenic effects in rats when administered i.p. at 1/3 – 1/30 of the i.p. LD50 values. Some effect on resorptions and abnormalities were seen with all but diethyl adipate.

Inhalation by rats of up to 1.0 mg/l of a mixture of dimethyl glutarate, dimethyl succinate, and dimethyl adipate on days 7-16 of gestation or for 14 days prior to mating, during mating and gestation, and lactation, produced no observed adverse developmental or reproductive effects. The only exception was a statistically significant decrease in pup weight at birth and day 21.

Dimethyl Malonate

The reproductive and developmental toxicity of dimethyl malonate was evaluated using groups of 10 male and 10

female Wistar rats.14 The animals were dosed with 0, 100, 300, or 1000 mg/kg bw dimethyl malonate orally, by gavage.

Males were dosed for 2 wks prior to mating, during mating, and 2 wks after mating, for a total of 39 doses. Females were

dosed 2 weeks prior to mating, during mating, and through day 4 of lactation. A recovery group of 5 male and 5 female high

dose animals were observed for 14 days after the termination of dosing. Microscopically, the incidence of treatment-related

hepatocellular hypertrophy of the liver was observed for males and females given 1000 mg/kg bw dimethyl malonate. This

effect was not observed in the recovery animals or in the other test groups. No other significant toxicological effects were

observed. Performance in a functional observation battery was similar for test and control animals. There was no effect on

fertility. In the 100 mg/kg bw group, a statistically significant decrease in the number of live pups was due to an increase in

post-implantation loss. This effect was not considered treatment related, and no developmental toxicity was reported. The

NOAEL was 300 mg/kg bw for repeated doses and maternal toxicity and 1000 mg/kg bw for fertility and developmental

toxicity.

Dimethyl Adipate

The fetotoxic and teratogenic effects of dimethyl adipate were evaluated in a study in which groups of 5 gravid

Sprague Dawley rats were dosed i.p. with 0.0603-0.6028 ml/kg (1/30, 1/10, 1/5, and 1/3 of the i.p. LD50 value) on days 5, 10,

and 15 of gestation.113 A pooled volume control consisted of animals dosed with 10 ml/kg distilled water, saline, or cotton-

seed oil. A positive control group was not used. All animals were killed and examined on day 20 of gestation. The mean

fetal weights and the numbers of live fetuses were not statistically significantly different between treated and blunt-needle

control groups. Resorptions in animals dosed with 0.1809 ml/kg were statistically significantly increased when compared to

the pooled controls, but not the blunt-needle controls. Gross and skeletal abnormalities, but not visceral, were statistically

significantly increased in fetuses of the 0.3617 and 0.6028 ml/kg groups.


39

Diethyl Adipate

The fetotoxic and teratogenic effects of diethyl adipate were evaluated following the same procedure described

above.113 These rats were dosed i.p. with 0.0837-0.8373 ml/kg diethyl adipate. The mean fetal weight and the number of live

fetuses were not statistically significantly different between treated and blunt-needle control groups, and the number of resorp-

tions was similar between treated animals and both the blunt needle and pooled controls. There were no differences in the

incidences of gross, skeletal, or visceral abnormalities in fetuses of the treated groups compared to pooled controls.

Dipropyl Adipate

The fetotoxic and teratogenic effects of dipropyl adipate were evaluated following the same procedure described

earlier.113 These rats were dosed i.p. with 0.1262-1.2619 ml/kg dipropyl adipate. The numbers of live and dead fetuses were

not statistically significantly different between treated and blunt-needle control groups, but there was a statistically significant

decrease in the mean fetal weight of the 0.7572 ml/kg group. Resorptions in animals dosed with 1.2619 ml/kg were statisti-

cally significantly increased when compared to the pooled controls, but not the blunt-needle controls. Gross abnormalities,

but not skeletal or visceral, were statistically significantly increased in fetuses of the 1.2619 ml/kg group.

Dibutyl Adipate

A reproductive toxicity study was performed in which groups of 5 gravid Sprague Dawley rats were dosed i.p. with 0.1748-1.7480 ml/kg dibutyl adipate on days 5, 10, and 15 of gestation. The incidence of gross abnormalities was only statistically significantly increased in the high dose group when compared to pooled controls.


The reproductive toxicity of dibutyl adipate was evaluated in a study Sprague-Dawley rats.104 Groups of 13 male

and 13 female rats were dosed with 0, 100, 300, or 1000 mg/kg bw dibutyl adipate orally, by gavage, for 14 days prior to mat-

ing through parturition; males were dosed for a total of 42 days and female dams were dosed until day 3 of lactation. The test

article had no effect on fertility. Body weight gains of males of the 1000 mg/kg bw group were slightly decreased. Kidney

weights of the high dose males and females sere increased compared to controls. No gross or microscopic effects were noted

at necropsy, and the internal genitalia were normal. Dosing with dibutyl adipate did not produce any reproductive effects.

The only effect on the offspring was a decrease in pup weight on post-natal days 0 and 4 and in viability on post-natal day 4.

The NOEL for parental and offspring toxicity was 300 mg/kg bw/day. The reproductive NOEL was 1000 mg/kg bw/day.


Groups of 24 gravid Sprague Dawley rats were dosed orally by gavage with 0, 1000, 4000, or 7000 mg/kg bw/day

di-C7-9 branched and linear alkyl esters of adipic acid on days 6-19 of gestation, and all animals were killed and examined on

day 20.86 All dams survived until study termination. Body weights were significantly decreased for dams of the 7000 mg/kg

bw group. Weights of male and female fetuses of the 7000 mg/kg bw group were slightly, but not statistically significantly,

decreased compared to the other groups. A greater incidence of rudimentary structures was observed for high dose fetuses as

compared to the other groups in this study, but the incidence was within the range of historical controls. There was no

evidence of developmental toxicity at any dose tested.

Ditridecyl Adipate

The reproductive and developmental toxicity of ditridecyl adipate was evaluated using groups of 15 mated female

Sprague-Dawley rats.86 Doses of 0, 800, and 2000 mg/kg bw were applied dermally without occlusion on days 0-19 of gesta-

tion, and the dams were killed on day 20. Mild skin irritation consisting of erythema and flaking were observed at the test sites

of the treated animals. No maternal mortality was reported. Weight gains were statistically significantly decreased for the


40

2000 mg/kg bw group during days 0-3 and 16-20 of gestation. Weight gain was statistically significantly decreased in the 800

mg/kg bw group during days 0-3 of gestation. No differences in skeletal anomalies were observed, but there were some

differences in visceral anomalies, including increased incidence of levocardia at 2000 mg/kg bw. These anomalies were not

considered treatment-related. The NOAEL for maternal toxicity was 2000 mg/kg bw/day, and for developmental and

reproductive effects it was 800 mg/kg bw/day.

Groups of 25 mated female rats were dosed dermally with 0 and 2000 mg/kg bw ditridecyl adipate following the

same study protocol as above. Again, there were no signs of maternal toxicity. No developmental toxicity was reported, and

there were no visceral anomalies or levocardia.

Tridecyl adipate, 2000 mg/kg bw, was applied, unoccluded, to groups of 10 male Sprague-Dawley rats, 5 days/wk

for 13 wks, and the effect on sperm morphology was evaluated.86 (The 'Subchronic Dermal Toxicity’ study was described

earlier.) No differences in sperm morphology were observed between control and test animals.

Diisobutyl Adipate

The fetotoxic and teratogenic effects of diisobutyl adipate were evaluated following the procedure described in the

earlier i.p. study.113 These rats were dosed i.p. with 0.1983-1.9833 ml/kg diisobutyl adipate. The numbers of live and dead

fetuses were not statistically significantly different between treated and blunt-needle control groups, but there was a statistical-

ly significant decrease in the mean fetal weight of the 1.1900 and 0.9833 ml/kg dose groups. The number of resorptions was

similar between treated animals and both the blunt needle and pooled controls. Gross abnormalities, but not skeletal or vis-

ceral, were statistically significantly increased in fetuses of the 0.5950 and 1.9833 ml/kg groups.


The reproductive effects of diethylhexyl adipate were studied in Swiss mice. Groups of 10 male mice were dosed i.p. with ≤9.3 g/kg and then mated with undosed females. A reduction in the number of gravid females was considered an anti-fertility effect, and the dominant lethal mutation was determined directly from the dose-dependent increase in the number of early fetal deaths and indirectly from the dose- and time-dependent decrease in implantations. There were no test article-related changes in the incidence of late fetal deaths. It was noted that the experimental design and interpretation have been questioned by some. Diethylhexyl adipate, ≤9.3 g/kg, was administered by i.p. injection to groups of 5 gravid Sprague Dawley rats on day 5, 10, and 15 of gestation. Resorption rates were similar to controls. A decrease in the mean fetal body weight and a significant increase in gross fetal abnormalities at the high dose were observed when compared to pooled control values. However teratogenic effects were not observed when compared to concurrent controls. It was stated that the lack of historical and positive controls affected the validity of the results.


Groups of 15 male and 30 female Wistar rats were fed a diet containing 0, 0.03, 0.18, or 1.2% diethylhexyl adipate

(calculated as 28, 170, or 1080 mg/kg bw/day) for 10 weeks prior to mating.86 Dosing was terminated, and the animals were

mated. (A different source indicated that dosing continued throughout the study).127 A reduction in body weight gain was

reported during gestation for the dams of the 1.2% group. No test article-related effects on fertility were observed. Fetal

weight, total litter weight, and litter size were reduced in the 1.2% group, but the number of pups born live, or their survival,

was not affected. The NOAEL was 170 mg/kg bw/day and the LOAEL was 1080 mg/kg bw/day.

In another study in which gravid females were fed the same doses as above on days 1-22 of gestation, maternal body

weight and feed consumption were statistically decreased in the 1.2% group. No significant effects on fetal weight or litter

size were reported. Animals of the 0.18 and 1.2% groups had slightly increased incidences of minor skeletal abnormalities;

this increase was attributed to fetotoxicity. The NOEL for maternal toxicity was 170 mg/kg bw/day. The NOAELs for

developmental toxicity and fetotoxicity were 170 and 28 mg/kg bw/day, respectively. The LOAEL was 1080 mg/kg bw day.

A dose-range finding study was performed using groups of 8 gravid Wistar rats that were dosed by gavage with 2


41

ml/kg of 0, 800, or 1200 mg/day diethylhexyl adipate, in peanut oil, from day 7 of gestation until day 17 after parturition.128

No signs of toxicity were reported in any of the groups. In the 800 mg/kg bw group, the only statistically significant

observation made was decreased body weights of male and female pups on day 3. In the 1200 mg/kg bw group, statistically

significant effects were observed for a number of parameters, including decreased maternal weight gain during days 7-21 of

gestation, increased length of gestation (by 1 day), decreased pup body weights at birth and day 3, and an increase in perinatal

loss per litter. (Perinatal loss was 42% in the 1200 mg/kg bw groups, as compared to 4.6% in controls.)

Based on the results of the dose-range finding study, groups of 20 gravid Wistar rats were dosed with 2 ml/kg of 0,

200, 400, or 800 mg/kg bw diethylhexyl adipate, in peanut oil, from day 7 of gestation until post-natal day 17. At postnatal

day 21, all dams and pups were killed, with the exception that one male and one female pup per litter was kept for further

evaluation. No signs of toxicity were reported in any of the groups. No significant effects were observed in the 200 mg/kg

bw group. In the 400 mg/kg bw dose groups, the number of postnatal deaths per number of pups was statistically significant

increased. In the 800 mg/kg bw group, statistically significant effects were observed for a number of parameters, including

increased length of gestation (by 1 day), decreased pup body weights at birth and days 3 and 13, increased mean number of

postnatal deaths, and an increase in postnatal death per number of pups. The percentage of perinatal loss per litter was twice

as high in the 400 and 800 mg/kg bw groups (23%) as compared to controls (11%), but the change was not statistically signi-

ficant. Testicular testosterone levels were unaffected in any of the pups that were killed on postnatal day 21 or the adult male

offspring, and serum luteinizing hormone and prolactin levels were similar to controls. None of the sperm parameters that

were evaluated were affected by dosing. The only statistically significant effects, noted in the 800 mg/kg bw group, were

increased relative liver to body weights in male pups on day 21 and increased body weights and decreased adrenal weights in

adult male offspring. Diethylhexyl adipate did not produce any antiandrogenic effects in the study. Fetal steroidogenesis was

not evaluated. NOAEL was 200 mg/kg bw.

Groups of 10 female Crl:CD(SD) rats were dosed with 5 ml/kg, by gavage, of 0, 200, 1000, or 2000 mg/kg bw

diethylhexyl adipate in corn oil for 2 wks prior to mating with undosed males, throughout mating, and until day 7 of

gestation.119 The dams were killed on day 14 of gestation. All animals survived until study termination. Body weights and

body weight gains were significantly decreased in the 2000 mg/kg bw dose group prior to mating. Staining around the

perineum was observed in the 1000 and 2000 mg/kg bw dose groups. No statistically significant differences were observed

for the 200 mg/kg bw group compared to controls. The mean estrous cycle length was statistically significantly increased in

the 1000 and 2000 mg/kg bw groups, and the post-implantation loss rate was also statistically significantly increased in these

groups. Additionally, in the 2000 mg/kg bw group, there was a significant decrease in implantation rate, and the number of

live embryos was statistically significantly decreased and the pre-implantation loss rate statistically significantly increased.

The researchers stated that the effects observed in this fertility study, in conjunction with the ovarian effects described earlier

in the repeated dose study, suggest that diethylhexyl adipate disturbed ovulation. This correlated with the effect on estrous

cycle length.

The testicular toxicity of diethylhexyl adipate was examined using male F344 rats.129 Groups of six rats were fed a

diet containing 6000 or 25,000 ppm diethylhexyl adipate for 4 wks, and the controls were given untreated feed. Some groups

were dosed i.p. with 200 mg/kg bw thioacetamide, 3x/wk for 4 wks, and prior to dosing with diethylhexyl adipate to evaluate

whether liver disease enhanced testicular effects. (There was a 1-wk rest period prior to dosing with diethylhexyl adipate.)

The final body weights of animals given 25,000 ppm diethylhexyl adipate, with and without prior administration of

thioacetamide, were statistically significantly decreased compared to their respective controls. The relative liver to body


42

weights of these animals were statistically significantly increased. No significant effect on the relative weights of the testes or

epididymis was seen for any of the test groups. Diethylhexyl adipate did not have any testicular toxic effects, with or without

the induction of hepatic damage.

Diisononyl Adipate

In a subchronic dietary study described earlier, groups of male and female Beagle dogs were fed 0, 0.3, 1.0, or 3.0%

(wks 1-8) and 6.0% (wks 9-13) diisononyl adipate for 13 wks.86 Reproductive tissues were evaluated. No significant findings

were reported for the 0.3 and 1.0% groups. In the high dose group, testes weight was decreased. At microscopic examina-

tion, it was found that the epididymal ducts were devoid of spermatozoa, the seminiferous tubules were composed of Sertoli

cells and spermatogonia, spermatocytes and spermatids were not evident, and there was almost total aspermatogenesis.

Ovaries were not weighed at necropsy. There were no gross or microscopic changes in the ovaries of the high dose group

compared to controls.

Dibutyl Sebacate

A test group of 20 male and 20 female Sprague-Dawley rats was fed a diet containing 6.25% dibutyl sebacate for 10

wks, while a control group of 12 male and 12 female rats were fed the basal diet, and then animals of each group were then

mated.114 The dams were allowed to deliver their litters, and at weaning, 24 male and 24 female offspring were randomly

chosen, fed the test diet for 21 days, and then killed for necropsy. The study results indicated that ingestion of a diet contain-

ing 6.25% dibutyl sebacate had no adverse effect on fertility, litter size, or survival of offspring. Growth was decreased dur-

ing the pre-weaning and post-weaning periods. However, no gross pathological changes were found among young rats killed

at the end of the 21-day post-weaning period.


Reproduction, suckling and growth were normal in a four-generation study of rats fed a diet containing 200 ppm

diethylhexyl sebacate (~10 mg/kg bw/day).1 No reproductive or developmental toxicity was observed.

Dimethyl Glutarate/Dimethyl Succinate/Dimethyl Adipate Mixture

The developmental toxicity produced by the inhalation of dibasic esters (mixture of 65.1% dimethyl glutarate, 17.8%

dimethyl succinate, and 16.8% dimethyl adipate) was evaluated in rats.130 Groups of 24 gravid Crl:CD rats were exposed for

6 h/day to 0, 0.16, 0.4, or 1.0 mg/l dibasic esters, by whole body inhalation, on days 7-16 of gestation. The aerosol particle

size in the 1.0 mg/l chamber was 5.3-5.4 µm, with 72-74% of the aerosol <10 µm. The animals were killed on day 21 of

gestation. All animals survived until study termination. Body weight gains were statistically significantly decreased in the 0.4

and 1.0 mg/l groups. Feed consumption by these groups was reduced during the first 6 exposures; statistical significance was

not given. Statistically significant differences in absolute and relative liver to body weights were not observed, but there was

a significant trend of decreased absolute, but not relative, liver weights. The only significant clinical signs observed were

perinasal staining and wet fur of rats in the 1.0 mg/l group. Reproductive and developmental effects were not observed, and

the dibasic esters mixture was not a developmental toxicant in rats following inhalation of ≤1.0 mg/l.

Groups of 20 Crl:CD(SD)BR rats/gender were exposed for 6 h/day, 5 days/wk, to 0, 0.16, 0.40, or 1.0 mg/l dibasic

esters by whole body inhalation for 14 wks prior to mating, and then 7 days/wk for 8 wks of mating, gestation, and lacta-

tion.131 The mean aerosol particle size in the 1.0 mg/l chamber was 6.2 µm, with 69% of the aerosol <10 µm. Exposure was

discontinued from day 19 of gestation through day 3 post-partum. All parental rats and 10 pups/gender were killed and

necropsied on day 21 post-partum. The remaining pups were not necropsied. Maternal body weights in the 0.40 mg/l group

were decreased during the last week of the study, while body weights of male and female rats of the 1.0 mg/l group were


43

slightly decreased from wk 7 on. Relative liver to body weights were slightly, but not significantly, decreased in the 0.4 and

1.0 mg/l groups. Other differences in organ weights were not considered dose-related. With the exception of a statistically

significant decrease in pup body weights at birth and day 21, no reproductive or developmental effects were observed. The

only microscopic findings were squamous metaplasia in the olfactory epithelium of all treated parental rats. This effect was

minimal in the 0.16 mg/l group and mild to moderate in the 0.4 and 1.0 mg/ml groups. The NOEL for reproductive

parameters was 1.0 mg/l.

Endocrine Disruption

Diethylhexyl adipate appeared to have endocrine-mediated effects in rats in a 28-day oral study; however, the findings may be attributable to the disturbance in ovarian function according to the hypothalamic-pituitary-gonad axis. Diethylhexyl adipate simulated thyroid hormone-dependent rat pituitary GH3 cell proliferation in a concentration-dependent manner.


A 28-day repeated-dose toxicity study was performed to determine whether diethylhexyl adipate has endocrine-

mediated activities.132 Groups of 10 male and 10 female Crj:CD (SD) rats were dosed orally by gavage with 0, 40, 200, or

1000 mg/kg bw diethylhexyl adipate in corn oil, at a volume of 10 ml/kg, for a minimum of 28 days. In addition to clinical

observations, a functional observation battery was performed during wk 4, estrous cycling was assessed from day 22,

hormone analysis was measured at the end of the test period, and sperm morphology and sperm count were examined. Male

animals were killed and necropsied on day 29, while females were killed and necropsied on days 30-34 when in diestrous.

Signs of toxicity were not observed, and no clinical chemistry or hematological findings were recorded. Hormonal and

spermatological analyses were normal. Statistically significant increased were seen in relative kidney to body weights in males

of the 200 and 1000 mg/kg bw groups, relative liver to body weights of males in the 1000 mg/kg bw group, and in relative

liver, kidney, and adrenal to body weights in females of the 1000 mg/kg bw group. Microscopically, increased eosinophilic

bodies and hyaline droplets were seen in the kidneys of male rats of the 1000 mg/kg bw group. Ovarian follicle atresia was

observed in 4 females of the 1000 mg/kg bw group, accompanied by a prolonged estrous cycle in 2 of these rats. A change in

the estrous cycle is an important endpoint for determination of endocrine-mediated effects in the enhanced TG 407 assay.

The researchers stated that this effect, in conjunction with the microscopic findings, appears to be related to endocrine-

mediated effects of diethylhexyl adipate. However, it was also stated that these findings may be attributable to the

disturbance of ovarian function according to the hypothalamic-pituitary-gonad axis. The changes in relative organ to body

weights were considered toxic effects, and the NOEL was 40 mg/kg bw/day.

The effect of diethylhexyl adipate on estrogen receptor and thyroid hormone (TH) functions was also examined.133

The TH-like activity was assessed using the rat pituitary tumor cell line Gh3 expressing intracellular TH and estrogen

receptors and responding to physiological concentration of TH by proliferation. At low potency, diethylhexyl adipate

stimulated the TH- dependent rat pituitary GH3 cell proliferation in a concentration-dependent manner. Cotreatment of GH3

cells with diethylhexyl adipate potentiated the L-3,5,3’-triiodothyronine (T3)-EC50 potentiated the T3-induced GH3 cell

proliferation.

GENOTOXICITY

The esters of dicarboxylic acids were not mutagenic or genotoxic in a battery of in vitro and in vivo tests. The only non-negative results reported were equivocal results in a sister-chromatid exchange assay with ≤400 µg/ml diethylhexyl adipate in the presence of metabolic activation and a dose-dependent inhibition of 3H-thymidine into replicating DNA, with a dose-dependent increase in the ratio of acid-incorporated 3H-thymidine with ≤0.01 M diethylhexyl adipate.. (The same effect was seen in the 3H-thymidine assay with 2-ethylhexanol.)

Details of the genotoxicity studies on esters of dicarboxylic acids are described in Table 12. Data from the original


44

safety assessments on dibutyl and diethylhexyl adipate are included in italics. Details of the available genotoxicity data on

esterase metabolites are also summarized in this table.

Diethyl Malonate

Diethyl malonate was not mutagenic in an Ames test or a cytogenetic assay using human peripheral lymphocytes at

concentrations ≤5000 µg/plate.14

Dimethyl Malonate Dimethyl malonate was not mutagenic in an Ames test at concentrations ≤5000 µg/plate.14

Dimethyl Succinate

Dimethyl succinate was not mutagenic in an Ames tests with concentrations of ≤ 20,000 µg/plate134 or in a

preincubation assay with concentrations of ≤10,000 µg/plate.135

Dimethyl Glutarate

Dimethyl glutarate was not mutagenic in a preincubation assay with concentrations of ≤10,000 µg/plate.136

Dimethyl Adipate

Dimethyl adipate was not mutagenic in a preincubation assay with concentrations of ≤10,000 µg/plate.137

Dibutyl Adipate

Dibutyl adipate was mutagenic in an Ames test at concentrations of ≤5000 µg/plate. It was not genotoxic in an in vivo mouse micronucleus assay in which the animals were dosed with ≤2000 mg/kg bw.



Di-C7-9 branched and linear alkyl esters of adipic acid were not mutagenic in an Ames test at concentrations of

≤10.0 µl/plate.86

Ditridecyl Adipate

Ditridecyl adipate was not mutagenic in an Ames test at concentrations of 0-10 µl/plate, and it was not clastogenic in

an in vivo micronucleus assay using rats dosed dermally with 0, 800, or 2000 mg/kg bw ditridecyl adipate.86


Diethylhexyl adipate was not mutagenic in an Ames. (The specific concentrations tested were not provided.)


Diethylhexyl adipate was not mutagenic in a number of genotoxicity studies. In vitro, negative results were reported

in Ames tests at concentrations ranging from ≤150 -10,000 µg/plate,86,138-140 in an NTP preincubation assay,141 in a liquid

suspension assay,142 and in a forward mutation assay using L5178Y cells at concentrations ≤1000 µg/ml .143 In an assay for

sister chromatid exchanges and chromosomal aberrations using concentrations of ≤200 µg/plate, results were negative,144

while in another assay with ≤400 µl/plate, results were negative without, but equivocal with, metabolic activation in the sister

chromatid exchange assay and there was some evidence of genotoxicity without, but none with, metabolic activation in the

chromosomal aberration assay.145 In a 3H-thymidine assay, there was a dose-dependent inhibition of 3H-thymidine incorpora-

tion into replicating DNA, with a dose-dependent increase in the ratio of acid-soluble DNA-incorporated 3H-thymidine.139 In

vivo, results were negative in micronucleus tests86,146 and chromosomal aberration assays.147,148

An Ames test was performed on urine of rats dosed with diethylhexyl adipate to assess whether mutagenic substances

occur in the urine following diethylhexyl adipate adminstration.149 Groups of ≥6 male Sprague-Dawley rats were dosed orally


45

by gavage with 0 or 2000 mg/kg bw diethylhexyl adipate in corn oil for 15 days. Urine was collected daily. The urine was

not mutagenic in the Ames test, indicating that diethylhexyl adipate is not converted to mutagenic urinary metabolites. The

urine of rats dosed with 1000 mg/kg bw 2-ethylhexanol by gavage for 15 days was also tested in an Ames assay. The urine of

these rats also was not mutagenic. Urine from rats that were dosed with a known mutagen gave a positive response in an

Ames test.

Diisononyl Adipate

Diisononyl adipate was not mutagenic in an Ames assay at ≤1000 µg/plate, and it was not genotoxic in a mouse

lymphoma assay, a transformation assay, or a BALB/3t3 assay at concentrations of ≤100, 1000, or 1.3 µg/ml, respectively.150

Diethyl Sebacate

Diethyl sebacate was non-mutagenic in an Escherichia coli Sd-4-73 reversion (streptomycin dependence to

independence) assay.151

Dibutyl Sebacate

Dibutyl sebacate, ≤10,000 µg/plate, was not mutagenic in the Ames assay.152,153


Diethylhexyl sebacate was not mutagenic in an Ames assay at concentrations of ≤10,000 µg/plate.138,154 In the rat

liver foci test, diethylhexyl sebacate demonstrated no evidence of promotion activity when administered orally at 500 mg/kg

bw 3x/wk for 11 wks, following a single oral treatment with a known carcinogen.155

CARCINOGENICITY

In an NTP 2-yr dietary study, ≤25,000 ppm diethylhexyl adipate did not produce tumors in male or female rats, but it did increase the incidence of hepatocellular adenoma and carcinoma in male and female mice. Diethylhexyl adipate did not cause skin tumors with weekly application of 10 mg to the back of mice in a lifetime study. Other compounds with a 2-ethyl-hexyl group that have been evaluated for carcinogenicity had some evidence of hepatocarcinogenicity, ranging from very strong to equivocal, in rodents. The IARC has stated that diethylhexyl adipate is not classifiable as to its carcinogenicity in humans. However, feeding of diethylhexyl sebacate to rats for 19 mos did not result in carcinogenic effects.


In an NTP carcinogenicity study, administration of ≤25,000 ppm diethylhexyl adipate to rats in the diet for 103 wks did not produce carcinogenic effects. However, mice fed the same amount for 103 wks had dose-related body weight reductions and a higher incidence of hepatocellular adenoma and carcinoma than the controls. In another study in which rats were fed ≤2.5% diethylhexyl adipate for 2 yrs, tumor incidence for the test animals was similar to that of controls. The same researchers found no tumors in dogs fed up to 0.2% diethylhexyl adipate for 1 yr. A single 10 mg dose of diethylhexyl adipate given by s.c. injection was not carcinogenic in mice. In a lifetime study, diethylhexyl adipate caused no skin tumors when 10 mg was applied weekly to the back skin of mice.


Research has shown that other compounds with a 2-ethylhexyl group that have been evaluated for carcinogenicity

had some evidence of hepatocarcinogenicity, ranging from very strong to equivocal, in rodents. 156

In an evaluation of the carcinogenic risk of diethylhexyl adipate, the IARC stated that there was limited evidence in

experimental animals for the carcinogenicity of diethylhexyl adipate.17 Therefore, the overall evaluation of diethylhexyl

adipate was not classifiable as to its carcinogenicity to humans (Group 3).


No evidence of carcinogenicity was observed in an unspecified number of rats fed a diet providing about 10 mg

diethylhexyl sebacate/kg/day for up to 19 months.1 No further study details were provided.


46

Tumor Promotion


A group of 14 male F344 rats were used to assess the carcinogenic potential of diethylhexyl adipate in a medium-

term liver bioassay.157 The rats were given a single i.p. dose of diethylnitrosamine, and 2 wks later they were given 20,000

ppm diethylhexyl adipate in the diet. At wk 3, a partial hepatectomy was performed. Positive results for carcinogenic

potential were indicated by a significant increase in GST-P positive foci. Diethylhexyl adipate did not have an enhancing

effect on the development of GST-P-positive foci.

CLINICAL ASSESSMENT OF SAFETY

Human Exposure


Diethylhexyl adipate can migrate into food, and it is most marked when plasticized PVC film comes in direct contact

with fatty foods.89 Using the analyses of a range of typical food, a maximum intake of 16 mg/person/day for diethylhexyl

adipate was estimated. The amount of diethylhexyl adipate used in PVC films was reduced, and the estimate was revised to

8.2 mg/day.

Dibutyl Sebacate

Dibutyl sebacate, a component of PVC, can pass from the packing films to the enclosed food.41

Dermal Irritation and Sensitization

In a number of irritation and sensitization studies, the diesters of dicarboxylic acids were not irritants or sensitizers. The only exception noted was that undiluted diisopropyl adipate was moderately irritating in one cumulative irritancy test, and some slight irritation was seen with formulations containing 0.01-9.0% diethylhexyl adipate.

Clinical dermal irritation and sensitization data on esters of dicarboxylic acids are presented in Table 13. Data from

the original safety assessments on dibutyl, diisopropyl and diethylhexyl adipate are included in italics. The available dermal

irritation and sensitization data on esterase metabolites are also summarized in this table.

Dimethyl Malonate

The sensitization potential of 8% dimethyl malonate in petrolatum was evaluated in a maximization test using 25

subjects.14 Dimethyl malonate was not a sensitizer.

Dibutyl Adipate

Undiluted dibutyl adipate was not irritating in a 24-hr clinical patch test with 10 subjects. Slight reactions (not defined) were reported for 4 of 18 subjects in a 24-h patch test with dibutyl adipate, 20% in alcohol.


Diisopropyl Adipate

The dermal irritation and sensitization of diisopropyl adipate was evaluated in a number of studies. Undiluted diisopropyl adipate produced no irritation in 4 h patch tests, but was moderately irritating in a 21-day cumulative irritancy test. Formulations containing 0.26-20.75% diisopropyl adipate caused minimal to mild irritation, but no sensitization.



The dermal irritation and sensitization of diethylhexyl adipate was evaluated in a number of studies with formulations containing 0.01-9% diethylhexyl adipate. Mild reactions were seen with a formulations containing 0.01%. Using a formulation containing 0.7%, on subject reacted strongly following the second challenge, with erythema and papules observed. Strong reactions were seen for 3 subjects in a patch test of a formulation containing 9.0% diethylhexyl adipate.



47

Diisostearyl Adipate

A human repeat insult patch test (HRIPT) using 50 subjects was used to evaluate the irritation and sensitization

potential of diisostearyl adipate.158 Two-tenths ml was applied neat to the back of each subject under an occlusive patch for

24 h, after which time the subject removed the patch. This procedure was performed 3 times per wk for 3 wks, for a total of 9

induction patches. Following a 10-14 day non-treatment period, a 24 h challenge patch was applied to a previously untreated

site, and reactions were scored at 24 and 48 h. No adverse reactions were observed, and diisostearyl adipate was not a

primary irritant or a sensitizer.

Diethyl Sebacate

A single insult occlusive patch test (SIOPT) was performed using 20 subjects to determine the irritation potential of

a body cream containing 1.5% diethyl sebacate.159 The test patch was applied for 24 h. The PII was 0.00, and the body

cream containing 1.5% diethyl sebacate was non-irritating.

The sensitization potential of a body cream containing 1.5% diethyl sebacate was evaluated in a maximization

study.160 During induction, 0.05 ml of 0.25% aq. sodium lauryl sulfate (SLS) was applied under an occlusive patch for 24 h.

At that time, the patch was removed and 0.05 ml of the test material was applied to the same site under an occlusive patch for

48-72 h. If no irritation was present at the test site upon patch removal, an occlusive patch with 0.25% aq. SLS was applied

for 24 h, followed by a patch of the test material. This sequence was used for 5 induction patches. If irritation developed

during induction, the SLS patch was eliminated. After a 10-day non-treatment period, a challenge was performed at a pre-

viously untreated site. The challenge site was pretreated with 0.05 ml of 5.0% aq. SLS under an occlusive patch for 1 h,

followed by an occlusive patch of the test material for 48 h. Twenty-five subjects completed the study. No reactions were

seen at challenge, and a body cream containing 1.5% diethyl sebacate did not have contact-sensitizing potential.


An SIOPT was performed using 20 subjects to determine the irritation potential of a foundation containing 1.8%

diisopropyl sebacate.161 The patch was applied for 24 h. The foundation containing 1.8% diisopropyl sebacate was not

irritating.

The irritation and sensitization potential of diisopropyl sebacate was evaluated in a patch test that consisted of four

24-h applications of diisopropyl sebacate as supplied (approximately 100%) during weeks 1, 2, 3, and 6 on a 2 cm x2 cm

area of skin on the right upper arm of each subject.162 Examinations were performed immediately after patch removal. The

induction phase was performed during wks 1-4 using 107 subjects. No clinically significant effects were detected on any of

the subjects during this phase. During wk 6, the challenge phase was conducted on 105 subjects. No clinically significant

effects were noted in any of the subjects during this phase. Diisopropyl sebacate was not observed to have any significant

skin-irritating or sensitizing activity under the conditions of this study.

A maximization assay was performed, using a modified protocol of the maximization assay procedure described

earlier, to determine the contact-sensitization potential of a foundation containing 2.2% diisopropyl sebacate.163 In this study,

the test material was allowed to volatilize for 30 min before the occlusive patch was applied. Twenty-five subjects completed

the study. No reactions were seen at challenge, and a foundation containing 2.2% diisopropyl sebacate did not have contact-

sensitizing potential.

Two heat protection hair spray products containing 1% diisopropyl sebacate were tested using a modified Draize

HRIPT procedure to determine the potential of those products to induce irritation and contact sensitization.164 The products

were tested neat and allowed to volatilize prior to patch application. Samples were patched under semi-occlusive conditions.


48

Approximately 0.2ml was used in each patch. One hundred ten subjects completed the study. Generally transient, barely

perceptible (0.5-level) to mild (1-level) patch test responses on 22 test subjects for one formulation and only barely per-

ceptible (0.5-level) patch test response on 15 test subjects with the other formulation during the induction and/or challenge

phases of the study were reported. Both products were considered to be non-irritating and non-sensitizing.

A heat protection hair spray product containing 7.2% diisopropyl sebacate was tested using an HRIPT to determine

the potential of this product to induce irritation and contact sensitization.165 The product was tested neat under semi-occlusive

conditions. Approximately 0.2 ml sample was used in each patch. Fifty-one subjects completed the study. No skin reactivity

was observed in any of the test subjects during the course of the study.


Diethylhexyl sebacate was applied neat using occlusive patches to the skin of 15-30 subjects (sex not specified) for

48-h.1 No local reactions were observed in the challenge phase (48-h covered contact with neat liquid) that was carried out 2

weeks later, presumably due to limited induction.


An HRIPT with 50 subjects was performed to evaluate the irritation and sensitization potential of dioctyldodecyl

dodecanedioate.158 Two-tenths ml of the test material, neat, was applied to the back of each subject under an occlusive patch

for 24 h, after which time the subject removed the patch. This procedure was performed 3 times per wk for 3 wks, for a total

of 9 induction patches. Following a 10-14 day non-treatment period, a 24 h challenge patch was applied to a previously

untreated site, and reactions were scored at 24 and 48 h. No adverse reactions were observed, and dioctyldodecyl dodecane-

dioate was not a primary irritant or a sensitizer.

Diisocetyl Dodecanedioate

An HRIPT with 50 subjects was performed as described above to evaluate the irritation and sensitization potential of

diisocetyl dodecanedioate.158 No adverse reactions were observed, and diisocetyl dodecanedioate was not a primary irritant

or a sensitizer.

Phototoxicity and Photosensitization

A 10% dilution of dibutyl adipate tested on 30 subjects and formulations containing 0.7-17% diisopropyl adipate, tested on 49-98 subjects, and 9% diethylhexyl adipate, tested on 25 subjects, were not phototoxic.

Dibutyl Adipate

Dibutyl adipate, as a 10% dilution in liquid paraffin, was not phototoxic in a clinical phototoxicity study using 30 subjects.5


Diisopropyl Adipate

In photopatch test studies using 49-98 subjects, formulations containing 0.7-17.0% diisopropyl adipate were not phototoxic, primary irritants, or sensitizers.



In a photopatch test on 9.0% diethylhexyl adipate using 25 subjects, no phototoxic or photoallergic reactions were observed.


Ocular Irritation

Dibutyl Adipate

Dibutyl adipate, 0.1% in paraffin oil, was not an ocular irritant in two subjects.


49


Comedogenicity

Dibutyl Adipate

Dibutyl adipate, 10-100% (vehicle not stated), was not comedogenic in clinical testing.


Case Reports

A number of investigators have reported cases of allergic contact dermatitis in response to diethyl sebacate-contain-

ing products, and have demonstrated diethyl sebacate to be the substance, or one of several substances in the products, elicit-

ing the dermatitis.37,166-170 Two case studies were reported of allergic reactions to lotion containing diisopropyl sebacate.171,172

In a case study where one patient was sensitized to other sebacate esters, diethylhexyl sebacate was not irritating.171 For

stearyl alcohol, a metabolite of distearyl succinate, contact sensitization was reported in 3 individuals.173 These case reports

are described in Table 14.

Risk Assessment


According to the Integrated Risk Information System of the EPA, the weight-of-evidence classification for diethyl-

hexyl adipate was “possible human carcinogen”.127 The classification was based on an absence of human data and increased

liver tumors in female mice. The only genotoxic effect was a positive dominant lethal assay. It was noted that diethylhexyl

adipate exhibits structural relationships to other non-genotoxic compounds that are classified as probable and possible

carcinogens.

SUMMARY

This safety assessment includes sebacic acid and other alkyl α,ω-dicarboxylic acids, salts, monoesters and diesters,

for a total of 56 ingredients. The dicarboxylic acids are terminally functionalized straight alkyl chains characterized by a sep-

aration between the acid functional groups of one to 10 carbons. The simple alkyl di-esters are the result of the condensation

of alkyl dicarboxylic acids and two equivalents of alkyl alcohols. These ingredients can be metabolized via hydrolysis back

to the parent alcohol, the mono-ester, and the parent dicarboxylic acid. The simple alkyl esters (mono- and di-) of these

dicarboxylic acids have straight or branched side chains ranging in length from one to 18 carbons. This safety assessment is

divided into two parts – (1) 12 dicarboxylic acids and their salts and (2) 44 esters of dicarboxylic acids.

A safety assessment of diethylhexyl adipate (called dioctyl adipate at the time of that assessment) and diisopropyl

adipate was published in 1984 with the conclusion that these ingredients are safe as used in cosmetics. This conclusion was

reaffirmed in 2006. Additionally, dibutyl adipate was previously reviewed in 1996 and the available data were found insuffi-

cient to support the safety of dibutyl adipate in cosmetic formulations. When re-reviewed in 2006, additional data were made

available to address the needs identified by the CIR Expert Panel, and an amended conclusion was issued stating that dibutyl

adipate is safe for use in cosmetic formulations.

While many of the alkyl dicarboxylic acids occur innatural products, commercial production of these acids has

historically occurred via alkali pyrolysis of lipids.

A relationship exists between the molecular weight and the log octanol – water partioning coefficient. Physical

properties change as chain length increases, and the water solubility of these acids is inversely proportional to their chain

length. Odd versus even chain length also plays a role. The alternating effects are believed to be the result of the inability of

odd carbon number compounds to assume an in-plane orientation of both carboxyl groups with respect to the hydrocarbon


50

chain. The diesters, in contrast, are much more lipid soluble and more difficult to dissolve in water. The short-chain alkyl

mono- and diesters are more soluble in water, less lipophilic, and relatively more volatile than the corresponding longer-chain

alkyl esters.

The ingredients included in this review would not be expected to have any meaningful ultraviolet absorption.

The ingredients in this report function in cosmetics as pH-adjusters, fragrance ingredients, plasticizers, skin-condi-

tioning agents and/or solvents and corrosion inhibitors. The majority of the dicarboxylic acids function in cosmetics as pH

adjusters and fragrance ingredients. Six of the 12 dicarboxylic acids and their salts and 24 of the 44 esters included in this

safety assessment are reported to be used in cosmetic formulations. For the dicarboxylic acids and their salts, disodium succi-

nate has the greatest number of reported uses, with a total of 45. The acid with the greatest concentration of use is succinic

acid, 26%; use at this concentration is in rinse-off products. The greatest leave-on concentration is 0.4%, disodium succinate,

with dermal contact exposure. For the esters, diisopropyl adipate has the greatest number of uses, with 70 reported. The con-

centration of use is greatest for dimethyl glutarate, 15% in a dermal rinse-off product. The ingredients with the greatest leave-

on use concentrations, which are all dermal contact exposures, are diethylhexyl adipate, 14%, diisostearyl adipate, 10%, and

diisopropyl sebacate, 10%. The dicarboxylic acids and their salts and esters are in the European Union inventory of cosmetic

ingredients.

Dicarboxylic Acids and Their Salts Dicarboxylic acids are natural metabolic products of the ω-oxidation of monocarboxylic acids when the β-oxidation

of free fatty acids is impaired. Under normal physiological conditions, dicarboxylic acids are rapidly β-oxidized, resulting in

very low cellular concentrations and practically non-detectable concentrations in the plasma. Oxidation of odd- and even-

numbered chains proceeds to different end points; even chains are completely, while odd-number chains are not completely,

oxidized.

Unchanged dicarboxylic acid was found in the urine of rats. With oral dosing, approximately 53-67% adipic acid,

40% azelaic acid, and 50% dodecanedioate was recovered with the respective acid. With i.v. dosing, 59-71% adipic acid and

35% sebacate was recovered. In humans, 6.76-61 adipic acid, and 61% azelaic acid were found in the urine after dosing with

the respective acid. With azelaic acid and dodecanedioic acid, radioactivity was found in all tissues, and it decreased after 24

h in all tissues except adipose tissue. Radioactivity was found in expired carbon dioxide at 24 h after dosing adipic acid

(70%), azelaic acid (14.5%), and disodium sebacate (25%). For rats dosed orally with azelaic, sebacic, undecanedioic, and

dodecanedioic acid, 2.5, 2.1, 1.8, and 1.6% of the respective acid was found in the urine unchanged. The amount recovered

decreased with increasing chain length. After oral dosing, 60, 17, 5, and 0.1% of azelaic, sebacic, decanedioic, and undecane-

dioic acids, respectively, were recovered unchanged in the urine. In the plasma of both animals and humans, dicarboxylic

acid catabolites that were 2-, 4-, or 6- carbons shorter than the corresponding dicarboxylic acid were found.

Adipic acid did not induce peroxisome proliferation. Dicarboxylic acids did have some cellular effects and inhibited

mitochondrial oxidoreductases, reversibly inhibited microsomal NADPH and cytochrome P450 reductase ,and competitively

inhibited tyrosinase in vitro.

The oral LD50 values of the dicarboxylic acids had a wide range; for example, adipic acid had values in rats ranging

from 0.94 g/kg to ≥11 g/kg.. Most reported values for the acids were >2 g/kg. The reported dermal LD50 values ranged from

>6 g/kg dodecanedioic acid to >10 g/kg glutaric acid.

In short-term oral toxicity studies, ≤3000 mg/kg bw/day adipic acid did not produce significant toxicological effects

in rats. Signs of toxicity were seen at >3600 mg/kg bw/day. No toxicity was observed with guinea pigs fed 400-600 mg/day


51

adipic acid. Short-term inhalation exposure to 126 mg/m3 adipic acid to rats did not produce signs of toxicity, but exposure of

mice to 460 mg/m3 resulted in decreased weight gain and produced effects in the upper respiratory tract, liver, kidneys, and

central nervous system.

In a subchronic oral study, 10 male and 10 female rats exposed to 10% sodium succinate in the drinking water died,

but no compound-related lesions were found. Body weights were decreased in rats given ≥2.5% sodium succinate for 13 wks,

but toxicological treatment-related changes were not observed. Glutaric acid had a low degree of toxicity to rats (at 2%) and

dogs (concentration not specified) when given in the drinking water. Dietary administration of ≤3400 mg/kg bw/day adipic

acid for 19 wks produced slight effects in the liver of male rats; the NOAEL was 3333 mg/kg bw. A mixture of adipic,

glutaric, and succinic acids had a low degree of toxicity in rats when tested at 3% for 90-days. Signs of toxicity were reported

in a subchronic inhalation study in which mice were exposed to 13 or 120 mg/m3 adipic acid.

Slight effects were seen in the livers of rats fed ≤3200 mg/kg bw/day adipic acid for 33 wks, and the NOAEL for rats

fed a diet containing adipic acid for 2 yrs was 1%; no significant toxicological effects were seen at concentrations of ≤5%.

No significant toxicological effects were observed for mice fed ≤280 mg/kg bw or rabbits fed ≤400 mg/kg bw azelaic acid for

180 days. Disodium sebacate was not toxic to rats or rabbits fed up to 1000 mg/kg bw for 6 mos.

For the dicarboxylic acids, the severity of ocular irritation seems to decrease with increasing carbon number. Suc-

cinic acid was a severe ocular irritant, glutaric acid was moderately irritating, and dodecanedioic acid was a slight irritant.

Ocular irritation produced by adipic acid was dose-dependent. Slight to mild dermal irritation was observed for the succinic,

glutaric, and adipic acid. Adipic acid, dodecanedioic acid, and a mixture of succinic, glutaric, and adipic acids are not

sensitizers.

Reproductive and developmental effects were not seen upon oral dosing with the dicarboxylic acids or disodium

sebacate. Malonic acid, at 0.1% in vitro, has a spermicidal effect on human spermatozoa. Glutaric acid was tested at doses of

≤1300 mg/kg bw in rats and 500 mg/kg bw in rabbits, adipic acid at doses of ≤263 mg/kg bw in mice, 288 mg/kg bw in rats,

205 mg/kg bw in hamsters, or 250 mg/kg bw in rabbits, azelaic acid at doses of ≤140 mg/kg bw in rats and 200 mg/kg bw in

rabbits, disodium sebacate at 500 mg/kg bw in rats and 1000 mg/kg bw in rabbits, and dodecanedioic acid was tested at

≤1000 mg/kg bw using rats. Embryotoxic effects were reported in a reproductive study of 2500 mg/kg bw/day azelaic acid

using rats and in reproductive studies with ≤500 mg/kg bw/day azelaic acid using rabbits and monkey. In vitro, sodium salts

of some dicarboxylic acid had a specific inhibitory effect on muscle activity of the uterine horn, and this effect progressively

increased with chain length.

The dicarboxylic acids are not genotoxic, and consistently were not mutagenic in Ames tests. Positive results were

seen in a transformation assay on glutaric acid using Balb/c-3T3 cells, both with and without metabolic activation. The

results of a mouse lymphoma assay, with and without metabolic activation, on glutaric acid were negative in a neutral pH

range. Equivocal results were obtained in an in vitro chromosomal aberration assay of ≤15 mg/ml disodium succinate using

Chinese hamster fibroblast cells. The dicarboxylic acids were not genotoxic in in vivo assays.

Carcinogenicity was not seen in rats given up to 2% sodium succinate in the drinking water or 5% adipic acid in feed

for 2 yrs. An increase in the incidence of C-cell adenoma/carcinoma of the thyroid in females given 2% sodium succinate,

and a positive trend in the occurrence of this tumor, was considered a function of experimental variability and not related to

dosing. Adipic acid was not carcinogenic when given orally to rats at up to 5% in the diet.

In a cumulative irritancy test, the cumulative irritation of a 15% azelaic acid gel increased with successive patching.

It is not known if the vehicle played a role in the irritation scores. Daily application of a 20% azelaic cream causes erythema


52

and irritation.

Esters of Dicarboxylic Acids

The metabolism of diesters in animals is expected to occur, initially, via enzymatic hydrolysis, leading to the corre-

sponding dicarboxylic acids and the corresponding linear or branched alcohol. These dicarboxylic acids and alcohols can be

further metabolized or conjugated to polar products that are excreted in urine, or, the enzymatic hydrolysis may be incomplete

and result, at least for some diesters, in the production of monoesters.

In in vitro absorption studies using pig skin, 8.8 and 3% of undiluted diethyl malonate was found in the skin and

receptor fluid, respectively, after 50 h. Absorption was enhanced when diethyl malonate was diluted with ethanol and re-

duced when diluted in acetone. Using human skin, 16% of the applied diethyl malonate penetrated in 24 h. In vivo, absorp-

tion of diethyl malonate, estimated from urinary and fecal recovery, was 15% in nude mice, 4% in human skin grafted to nude

mice, 6% in pig skin grafted to nude mice, 2.5% in pigs, and 4% in dogs.

Approximately 11% of ditridecyl adipate was absorbed through the skin of rats; 5.5-7.4% of the applied dose was

found in the tissues, 3.5-4.7%was found in the urine, and 0.4-0.7% was found in the feces after 4 days. Prior dosing with

ditridecyl adipate did not significantly affect absorption.

In vitro, diethylhexyl adipate was readily hydrolyzed to mono-(2-ethylhexyl) adipate (MEHA) or adipic acid in rat

liver, pancreas, and small intestine tissue preparations. In animals, diethylhexyl adipate is hydrolyzed to adipic acid and 2-

ethylhexanol or MEHA. 2-Ethylhexanol is converted to 2-ethylhexanoic acid, which may form a glucuronide conjugate or

may be subjected to ω- and (ω-1)-oxidation and further metabolism. More than 98% of diethylhexyl adipate administered

orally to rats was excreted in 48 h; 21-45% of the radioactivity was expired in carbon dioxide and 34-52% was excreted in the

urine. Diethylhexyl adipate and MEHA are not found in the blood or urine; diethylhexyl adipate or the metabolites are

recovered in the tissues. Metabolism studies have shown that excretion in the urine is not as unchanged diethylhexyl adipate;

mostly adipic acid is found. In humans, peak urinary elimination of all metabolites occurred within 8 h of dosing.

Diethylhexyl sebacate is not readily absorbed through the skin of guinea pigs. Metabolism in rodents and humans

may follow partially common pathways, producing 2-ethylhexanol as an intermediary metabolite.

Diethylhexyl adipate is a peroxisome proliferator requiring extensive phase I metabolism to produce the proximate

peroxisome proliferator, which in both mice and rats appears to be 2-ethylhexanoic acid. Diethylhexyl adipate is not as potent

a proliferator as diethylhexyl phthalate. Peroxisome proliferation causes an increase in liver weights and can induce

hepatocarcinogenicity in rats and mice. Peroxisome proliferation is not believed to pose the risk of inducing hepatocarcino-

genesis in humans, as a species difference in response to peroxisome proliferators exists.

Diethylhexyl adipate did not bind covalently to hepatic DNA in mice. It did stimulate DNA synthesis in livers of

rats. In another study, a statistically significant increase in 8-OH-dG occurred in the liver DNA, but not the kidney DNA, at

wk 1 and 2. The IARC remarked that the weight of evidence for diethylhexyl adipate demonstrated that rodent peroxisome

proliferators do not act as direct DNA-damaging agents.

The oral and dermal LD50 values are greater than 2 g/kg. No mortality occurred in rats exposed to concentrated

vapors of diethyl malonate diethyl succinate, dibutyl adipate, or diethylhexyl adipate for 8 h. Some deaths, possibly due to

thermal decomposition were seen in rats and rabbits exposed to 940 mg/m3 for 7 h. In a 4-hr inhalation toxicity study, a mix-

ture of dimethyl glutarate, dimethyl succinate, and d¬methyl adipate, the anterior and posterior nasal passageways were

affected.

Oral administration of ≤1000 mg/kg bw dibutyl adipate for 28 days was not toxic effects in rats. In short-term oral


53

dosing with diethylhexyl adipate, decreased weight gain was reported for rats and mice. The NOELs for rats and mice were 2

and 0.63%, respectively, in feed; 5/5 female mice fed 10% dibutyl adipate in feed died. In 2- and 4-wk studies of diethylhexyl

adipate, the oral NOAEL for ovarian toxicity was 200 mg/kg bw in rats; an increase in atresia of the large follicle and a

decrease in currently formed corpora lutea were seen in females dosed with 1000 and 2000 mg/kg bw diethylhexyl adipate.

In a short-term dermal study in which 10 rabbits were dosed dermally with 0.5 or 1.0 ml/kg of a 20% dispersion of

dibutyl adipate for 6 wks, there was a significant decrease in body weights in the high dose group, and renal lesions in one

animal of each group. There were no signs of toxicity in guinea pigs in an immersion study with 20.75% diisopropyl adipate,

diluted to an actual concentration of 0.10% adipate. Dermal administration of diethylhexyl adipate to rabbits for 2 wks

resulted in slight to moderate erythema at the test site, but toxic effects were not reported for most of the animals.

In a 90-day oral toxicity study using rats, the NOEL for diethyl malonate was 1000 mg/kg bw/day. Dietary admini-

stration of ≤2.5% di-C7-9 branched and linear alkyl esters of adipic (approx. 1500 and 1900 mg/kg bw/day for males and

females, respectively) for 90 days did not result in systemic toxicity. The NOAELS for male and female rats were 1500 and

1950 mg/kg bw/day, respectively. Subchronic oral administration of diethylhexyl adipate to rats caused significant decreases

in body weight gains and increases in liver and kidney weights. The dietary NOEL for rats in a 90-day study was 610 mg/kg

bw. A decrease in body weights was seen in mice fed a diet with 1.2 and 2.5% diethylhexyl adipate. For diisononyl adipate,

dietary administration of up to 500 mg/kg bw for 13 wks, a statistically significant increase in relative kidney weights was

reported, but there were no toxicological findings. With dogs, 3.0% dietary diisononyl adipate resulted in a decrease in body

weights, testes weight, and feed consumption, increased liver weight, elevated enzyme levels, liver and kidney discoloration,

and microscopic changes in the liver, testes, spleen, and kidneys.

No adverse effects were reported with whole-body application of a 6.25% emulsion of dibutyl adipate to dogs 2x/wk

for 3 mos. Unoccluded dermal application of up to 2000 mg/kg bw ditridecyl adipate for 13 wks to rats produced slight

erythema, but no systemic toxicity.

In a 6-mos study in which rats were dosed intragastrically with diethylhexyl adipate, hepatic detoxification appeared

depressed at the beginning of the study, while in a 10-mos study, a decrease in central nervous system excitability was noted.

Dietary administration of ≤1.25% dibutyl sebacate for 1 yr or ≤6.25% for 2 yrs did not have an effect on growth

Ocular irritation appeared to lessen in severity as chain length of the dicarboxylic acid esters increased. Undiluted

diethyl malonate was slightly to moderately irritating to rabbit eyes. Dibutyl, diisopropyl, and diethylhexyl adipate, at

concentrations ranging from 0.1 – 100%, were non- or minimal ocular irritants. Diisopropyl sebacate was minimally

irritating. Diethylhexyl sebacate was non-irritating in an MTT viability assay. Undiluted dioctyldodecyl and diisocetyl

dodecanedioate were not irritating to rabbit eyes.

The esters of dicarboxylic acids were mostly non- or mildly irritating to rabbit skin. Some minimal irritation was

seen with diisopropyl adipate, undiluted or at 5-20.75% in formulation, and moderate erythema was reported with undiluted

dibutyl adipate. Dimethyl malonate, dibutyl and diethylhexyl adipate, diethylhexyl sebacate, and dioctyldodecyl

dodecanedioate were not sensitizers in guinea pigs or rabbits. Perfume formulations containing 1.1% diisopropyl adipate

were not phototoxic in rabbits.

Oral administration of up to 1000 mg/kg bw dimethyl malonate to Wistar rats did not have an effect on fertility, and

no developmental toxicity was reported. The NOAEL was 300 mg/kg bw for repeated dose and maternal toxicity and 1000

mg/kg bw for fertility and developmental toxicity. Oral administration of up to 100 mg/kg bw dibutyl adipate to Sprague-

Dawley rats did not cause any reproductive effects, and the NOEL for parental and offspring toxicity was 300 mg/kg bw/day


54

and for reproductive toxicity was 100 mg/kg bw/day. Oral administration of ≤7000 mg/kg bw di-C7-9 branched and linear

alkyl esters of adipic acid to Sprague-Dawley rats did not result in developmental toxicity. Dietary administration of up to

1.2% diethylhexyl adipate did not affect fertility when fed to rats prior to mating. Fetal weight, total litter weight, and litter

size were reduced with 1.2% diethylhexyl adipate. In a study in which gravid rats were fed the same doses during gestation,

no significant effects on fetal weight or litter size were reported. An increased incidence of minor skeletal abnormalities was

attributed to fetotoxicity. In a study in which diethylhexyl adipate was given orally to rats from day 7 of gestation until post-

natal day 17, antiandrogenic effects were not observed, although some increase in post-natal death was observed. Administra-

tion of up to 2000 mg/kg bw diethylhexyl adipate prior to dosing and through day 7 of gestation did have an effect on the

mean estrous cycle length at a dose of 1000 and 2000 mg/kg bw, and did appear to disturb ovulation. Significant decreases

were also seen in implantation rate and number of live embryos, as well as an increase in pre-implantation loss. Diethylhexyl

adipate did not produce testicular toxic effects in male F344 rats when fed at up to 25,000 ppm in the diet for 4 wks. Dietary

administration of 6.25% dibutyl sebacate to male and female Sprague-Dawley rats for 10 wks prior to mating had no adverse

effects on fertility, litter size, or survival of offspring. Diethylhexyl sebacate, 200 ppm in the diet, did not produce reproduc-

tive or developmental effects in rats.

Dermal applications of 2000 mg/kg bw ditridecyl adipate did not have an effect on sperm morphology. Some

visceral anomalies were reported. The NOAELs for maternal toxicity and developmental and reproductive effects were 2000

and 800 mg/kg bw/day, respectively.

Dimethyl, diethyl, dipropyl, dibutyl, diisobutyl, and diethylhexyl adipate were evaluated for fetotoxic and teratogenic

effects in rats when administered i.p. at 1/3 – 1/30 of the i.p. LD50 values. Some effect on resorptions and abnormalities were

seen with all but diethyl adipate.

Inhalation by rats of ≤1.0 mg/l of a mixture of dimethyl glutarate, dimethyl succinate, and dimethyl adipate on days

7-16 of gestation or for 14 days prior to mating, during mating and gestation, and lactation, no adverse developmental or re-

productive effects were observed. The only exception was a statistically significant decrease in pup weight at birth and day

21.

Diethylhexyl adipate appeared to have endocrine-mediated effects in Crj:CD (SD) rats in a 28-day oral study; how-

ever, it was stated that the findings may be attributable to the disturbance in ovarian function according to the hypothalamic-

pituitary-gonad axis. Diethylhexyl adipate simulated thyroid hormone-dependent rat pituitary GH3 cell proliferation in a

concentration-dependent manner.

The esters of dicarboxylic acids were not mutagenic or genotoxic in a battery of in vitro and in vivo tests. The only

non-negative results reported were equivocal results in a sister-chromatid exchange assay with ≤400 µg/ml diethylhexyl

adipate in the presence of metabolic activation and a dose-dependent inhibition of 3H-thymidine into replicating DNA, with a

dose-dependent increase in the ratio of acid-incorporated 3H-thymidine with ≤0.01 M diethylhexyl adipate.. (The same effect

was seen in the 3H-thymidine assay with 2-ethylhexanol.)

In an NTP 2-yr dietary study, ≤25,000 ppm diethylhexyl adipate did not produce tumors in male or female rats, but it

did increase the incidence of hepatocellular adenoma and carcinoma in male and female mice. Diethylhexyl adipate did not

cause skin tumors with weekly application of 10 mg to the back of mice in a lifetime study. Other compounds with a 2-ethyl-

hexyl group that have been evaluated for carcinogenicity had some evidence of hepatocarcinogenicity, ranging from very

strong to equivocal, in rodents. Feeding of diethylhexyl sebacate to rats for 19 mos did not result in carcinogenic effects.

In a number of clinical irritation and sensitization studies, the diesters of dicarboxylic acids are not irritants or


55

sensitizers. The only exception noted was that undiluted diisopropyl adipate was moderately irritating in one cumulative

irritancy test, and some slight irritation was seen with formulations containing diethylhexyl adipate. A 10% dilution of dibutyl

adipate tested on 30 subjects and formulations containing 0.7-17% diisopropyl adipate, tested on 49-98 subjects, and 9%

diethylhexyl adipate, tested on 25 subjects, were not phototoxic.

Cases of allergic contact dermatitis in response to diethyl sebacate-containing products have been reported, and it

has been demonstrated that diethyl sebacate was the substance, or one of several substances in the products, eliciting the

dermatitis. Two case studies were reported of allergic reactions to lotion containing diisopropyl sebacate.

According to the Integrated Risk Information System of the EPA, the weight-of-evidence classification for diethyl-

hexyl adipate was “possible human carcinogen”. The classification was based on an absence of human data and increased

liver tumors in female mice. The IARC has stated that diethylhexyl adipate is not classifiable as to its carcinogenicity in

humans.

DISCUSSION

The Expert Panel reviewed the available data on dicarboxylic acids and their salts, and the data on the esters of

dicarboxylic acids, and determined that these ingredients are safe as used in cosmetics. In reaching this conclusion, the

Expert Panel discussed a number of issues.

The Panel noted that the only significant toxic effect of the dicarboxylic acids was irritation to the skin and eyes,

which would be expected for acids. Dicarboxylic acids reviewed in this safety assessment are not expected to be appreciably

absorbed from cosmetic formulations, exhibit no single-dose or repeated-dose toxicity in animal studies, and are not

genotoxic or carcinogenic in animal studies. Since a use of these acids in cosmetics is as a pH adjuster, the irritating property

of these acids would be lost. Any uses as fragrance ingredients are at concentrations too low to produce irritation; the highest

leave-on use of an acid used as a fragrance ingredient is 0.4%. Although rinse-off products can contain higher concentrations

of these acids, contact time is short and the product will be diluted as it is being rinsed.

Case studies have reported reactions to products containing diethyl sebacate. Follow-up patch tests performed with

≥5% diethyl sebacate, which is greater than the reported use concentration, had positive results. Diethyl sebacate is reported

to be used in cosmetics at 1.5%, and no irritation or sensitization was reported in clinical studies of a formulation containing

1.5% diethyl sebacate.

A concern was expressed regarding the extent of dermal absorption for certain long-chain, branched diesters (which

have molecular weights greater than 500 g/mol and log Kow values of 10 or greater). In this view, were it demonstrated that

dermal penetration was low for the entire group, no further data would be needed. If not, then a concern was expressed about

the absence of toxicity data for several branched-chain alcohols that would be produced if dermal penetration and subsequent

metabolism could occur. The prevailing Panel view was that because dermal penetration of long chain alcohols is likely to be

low, and the dermal penetration for diesters is likely to be even lower, inferring toxicity characteristics from ingredients where

toxicity data were available was appropriate.

The Expert Panel also noted that esters of dicarboxylic acids, in particular diethylhexyl adipate, have the potential to

induce peroxisome proliferation. This effect has been examined because ethylhexyl adipate is structurally related to a notable

peroxisome proliferator, diethylhexyl phthalate. Diethylhexyl adipate is not as potent a peroxisome proliferator as diethyl-

hexyl phthalate, and, while peroxisome proliferation is toxicologically well-studied, this is an effect observed only in rodents

and is not relevant to humans. Accordingly, the hepatocarcinogenic effects observed in rodents are related to this effect and

not believed to pose the risk of inducing hepatocarcinogenesis in humans.


56

The reproductive and developmental toxicity of the dicarboxylic acids and their esters were generally well studied.

The results of these studies did not cause any concern for the Panel.

The potential adverse effects of inhaled aerosols depend on the specific chemical species, the concentration and the

duration of the exposure and their site of deposition within the respiratory system. In practice, aerosols should have at least

99% of their particle diameters in the 10 – 110 µm range and the mean particle diameter in a typical aerosol spray has been

reported as ~38 µm. Particles with an aerodynamic diameter of ≤ 10µm are respirable. In the absences of inhalation toxicity

data, the panel determined that alkyl PEG ethers can be used safely in hair sprays, because the product size is not respirable.

The Panel was also concerned with the dangers inherent in using animal-derived ingredients, namely the transmission

of infectious agents. The CIR Expert Panel stressed that these ingredients must be free of detectible pathogenic viruses or

infectious agents (e.g. Bovine Spongiform Encephalopathy (BSE)). Suppliers and users of these ingredients must accept

responsibility for assuring that these ingredients are risk-free. Tests to assure the absence of a pathogenic agent in the

ingredients, or controls to assure derivation from pathogen-free sources are two approaches that should be considered.

The CIR accepts the FDA determination that, to assure the absence of a pathogenic agent, sebacic acid and its salts

and esters must be made from tallow containing a maximum level of insoluble impurities of 0.15% in weight.


57

CONCLUSION

The CIR Expert Panel concluded that dicarboxylic acids and their salts and the esters of dicarboxylic acids, as listed

below, are safe in the present practices of use and concentration. Were ingredients in these groups not in current use to be

used in the future, the expectation is that they would be used in product categories and at concentrations comparable to others

in these groups.

Acids and salts: malonic acid succinic acid sodium succinate disodium succinate

glutaric acid adipic acid azelaic acid dipotassium azelate

disodium azelate sebacic acid disodium sebacate dodecanedioic acid

Esters: diethyl malonate decyl succinate dimethyl succinate diethyl succinate dicapryl succinate dicetearyl succinate diisobutyl succinate diethylhexyl succinate dimethyl glutarate diisobutyl glutarate diisostearyl glutarate dimethyl adipate diethyl adipate dipropyl adipate dibutyl adipate

dihexyl adipate dicapryl adipate di-C12-15 alkyl adipate ditridecyl adipate dicetyl adipate diisopropyl adipate diisobutyl adipate diethylhexyl adipate diisooctyl adipate diisononyl adipate diisodecyl adipate dihexyldecyl adipate diheptylundecyl adipate dioctyldodecyl adipate diisocetyl adipate

diisostearyl adipate isostearyl sebacate diethyl sebacate dibutyl sebacate dicaprylyl/capryl sebacate diisopropyl sebacate diethylhexyl sebacate dibutyloctyl sebacate diisooctyl sebacate dihexyldecyl sebacate dioctyldodecyl sebacate diisostearyl sebacate dioctyldodecyl dodecanedioate diisocetyl dodecanedioate


58

FIGURES

Figure 1a. Map of the malonic and succinic ester ingredients in this assessment, and associated esterase metabolites

Legend

Safe as used

* Not in ICI Dictionary and Handbook, 13th Ed.

Ingredients which have not been previouslyassessed and are part of this review

Safe for use with qualif ications

Result of Esterase metabolism

Ingredients which are concurrently under reviewin another report

Succinic Acid

Decyl Succinate

O

HO

O

O

O

HO

O

OH

CH3

Decyl alcoholCH3HO

O

O

O

OH3CCH3

Dimethyl Succinate

HOCH3

Methyl alcohol

O

O

O

O CH3H3CHO CH3

Ethyl alcohol

O

O

O

O(CH2)7CH3CH3(CH2)7

Diethyl Succinate

Dicapryl SuccinateCaprylic alcoholCH3HO

O

O

O

O(CH2)15CH3CH3(CH2)15

Dicetearyl Succinate

O

O

O

O(CH2)17CH3CH3(CH2)17

H3C OH

H3C OH

Cetyl alcohol

Stearyl alcohol

O

O

O

O

Diisobutyl SuccinateCH3

CH3

H3C

CH3

H3C

CH3OH

Isobutyl alcohol *

O

O

O

O

Diethylhexyl Succinate(CH2)3CH3CH3(CH2)3

Ethylhexyl alcohol *

CH3

H3C

OH

H3C

H3C

Isobutyl Succinate

Ethyl Succinate

Capryl Succinate

Cetearyl Succinate

*

*

*

*

*

O

O

O

OHH3C

O

O

O

OHH3C

O

O

O

OHCH3(CH2)7

O

O

O

OHCH3(CH2)nn = 15 or 17

O

O

O

OHH3C

CH3

O

O

O

OHCH3(CH2)3

H3C

Ethylhexyl Succinate*

Methyl Succinate


59

Figure 1b. Map of the glutaric and straight-chain adipic ester ingredients in this assessment, and associated esterase metabolites

Adipic Acid

O

HO

HOCH3

Methyl alcohol

HO CH3

Ethyl alcohol

Caprylic alcoholCH3HO

CH3OH

Cetyl alcohol

OH

O

O

OO

O

CH3H3C

Dimethyl Adipate

O

OO

ODiethyl Adipate

HO

Propyl alcohol

O

OO

ODipropyl Adipate

CH3

CH3H3C

H3CCH3

HO

Butyl alcohol

O

OO

ODibutyl Adipate

CH3H3C CH3

HO

Hexyl alcohol

O

OO

O

(CH2)5CH3CH3(CH2)5

Dihexyl Adipate

CH3

O

OO

O

(CH2)7CH3CH3(CH2)7

Dicapryl Adipate

O

OO

O

(CH2)15CH3CH3(CH2)15

Dicetyl Adipate

Lauryl alcoholHO

O

OO

O

(CH2)nCH3CH3(CH2)n

Di-C12-15 Alkyl Adipate

CH3

Tridecyl alcoholHO

CH3

Myristyl alcoholHO CH3

HOCH3

Heptadecyl alcohol

O

OO

O

(CH2)12CH3CH3(CH2)12

Ditridecyl Adipate

n = 11-14

Methyl Adipate*

Ethyl Adipate*

Propyl Adipate*

Butyl Adipate*

Hexyl Adipate*

Caprylic Adipate*

C12-15 Alkyl Adipate*

Tridecyl Adipate*

Cetyl Adipate*

O

OOH

O

H3C

O

OOH

O

H3C

O

OOH

O

H3C

O

OOH

O

H3C

O

OOH

O

CH3(CH2)5

O

OOH

O

CH3(CH2)7

O

OOH

O

CH3(CH2)n n = 11-14

O

OOH

O

CH3(CH2)12

O

OOH

O

CH3(CH2)15

*


60

Figure 1c. Map of the branched chain adipic ester ingredients in this assessment, and associated esterase metabolites

H3C

CH3OH

Isobutyl alcohol *

Ethylhexyl alcohol

OH

H3C

H3C

O

OO

O

H3C

CH3CH3

CH3

Diisobutyl Adipate

H3C OH

CH3Isopropyl alcohol

O

OO

O

H3C CH3

Diisopropyl AdipateCH3

CH3

O

OO

O

CH3(CH2)3(CH2)3CH3

Diethylhexyl Adipate (DEHA)H3C

CH3

Adipic Acid

O

HOOH

O

O

O

O

O(CH2)5(CH2)5

H3C

H3CCH3

CH3

Diisooctyl AdipateIsooctanol

H3C OH

O

O

O

O(CH2)6(CH2)6

H3C

H3CCH3

CH3

Diisononyl Adipate

Isononyl alcohol *

OHH3C

CH3

O

O

O

O(CH2)7(CH2)7

H3C

H3CCH3

CH3

Diisodecyl Adipate

H3C OH

CH3

CH3

Isodecyl alcohol *

O

O

O

O(CH2)7CH3CH3(CH2)7

CH3(CH2)4

(CH2)4CH3

H3C OH

H3C

HexyldecanolDihexyldecyl Adipate

O

O

O

O(CH2)8CH3CH3(CH2)8

CH3(CH2)5

(CH2)5CH3

Diheptylundecyl AdipateHeptylundecanol

H3COH

H3C

O

O

O

O(CH2)9CH3CH3(CH2)9

CH3(CH2)6

(CH2)6CH3

Dioctyldodecyl AdipateOctyldodecanol

H3C OH

H3C

O

O

O

O(CH2)13(CH2)13

H3C

H3CCH3

CH3

Diisocetyl Adipate

CH3OH

Isocetyl alcohol

O

O

O

O(CH2)15(CH2)15

H3C

H3CCH3

CH3


OH

Isostearyl alcoholCH3

Isopropyl Adipate*

Isobutyl Adipate*

monoester

*

Isooctyl Adipate*

Isononyl Adipate*

Isodecyl Adipate*

Hexyldecyl Adipate*

Heptylundecyl Adipate*

Octyldodecyl Adipate*

Isocetyl Adipate*

Isostearyl Adipate*

(Branched esters)

O

OOH

O

H3C

CH3

O

OOH

O

H3C

CH3

O

OOH

O

CH3(CH2)3

H3CEthylhexyl Adipate

O

O

O

OH(CH2)5H3C

H3C

*

O

O

O

OH(CH2)6H3C

H3C

O

O

O

OH(CH2)7H3C

H3C

O

O

O

OHCH3(CH2)7

CH3(CH2)4

O

O

O

OHCH3(CH2)8

CH3(CH2)5

O

O

O

OHCH3(CH2)9

CH3(CH2)6

O

O

O

OH(CH2)13H3C

H3C

O

O

O

OH(CH2)15H3C

H3C

CH3

CH3


61

Figure 1d. Map of the sebacic and dodecanedioic ester ingredients in this assessment, and associated esterase metabolites

HO CH3

Ethyl alcohol

Decyl alcohol

CH3HO

HO

Butyl alcoholCH3

HO

Caprylic alcohol

O

HO

O

OH

Sebacic Acid

O

O

O

OH3C CH3

O

O

O

OCH3(CH2)3(CH2)3CH3

O

O

O

OCH3(CH2)n(CH2)nCH3

O

HO

O

O(CH2)15

CH3

CH3

O

O

O

OH3C CH3

CH3

CH3

O

O

O

OCH3(CH2)3(CH2)3CH3

CH3

H3C

O

O

O

OCH3(CH2)5(CH2)5CH3

(CH2)2CH3

CH3(CH2)2

O

O

O

O(CH2)5

CH3

CH3(CH2)5

H3C

H3C

O

O

O

OCH3(CH2)7(CH2)7CH3

(CH2)4CH3

CH3(CH2)4

O

O

O

OCH3(CH2)9(CH2)9CH3

(CH2)6CH3

CH3(CH2)6

O

O

O

O(CH2)15

CH3

CH3(CH2)15

H3C

H3C

Ethyl Sebacate*

Butyl Sebacate*

Caprylyl/Capryl Sebacate*

Diethyl Sebacate

Dibutyl Sebacate

n = 7 or 9

Dicaprylyl/Capryl Sebacate

Isostearyl Sebacate

Isopropyl Sebacate*

Ethylhexyl Sebacate*

Butyloctyl Sebacate*

Isooctyl Sebacate*

Hexyldecyl Sebacate*

Octyldodecyl Sebacate*

H3C OH

CH3Isopropyl alcohol

CH3

Ethylhexyl alcohol *

OH

H3C

H3C

H3C OH

H3C

Butyloctanol

H3COH

CH3

Isooctanol

H3C OH

H3C

Hexyldecanol

Octyldodecanol

H3C OH

H3C

H3COH

CH3 Isostearyl alcohol



Dibutyloctyl Sebacate

Diisooctyl Sebacate

Dihexyldecyl Sebacate

Dioctyldodecyl Sebacate

Diisostearyl Sebacate

O

O

O

OHH3C

O

O

O

OHCH3(CH2)3

O

O

O

OHCH3(CH2)n

O

O

O

OHH3C

CH3

O

O

O

OHCH3(CH2)3

H3C

O

O

O

OHCH3(CH2)5

CH3(CH2)2

O

O

O

OH(CH2)5H3C

H3C

+

O

O

O

OHCH3(CH2)7

CH3(CH2)4

+

O

O

O

OHCH3(CH2)9

CH3(CH2)6

+

n = 7 or 9


Figure 2. Sebacic acid synthesis from castor oil.

Figure 3. Diethylhexyl adipate synthesis from adipic acid.


63

CHARTS

Chart 1. Dicarboxylic Acids; Log Kow vs Molecular Weight


64

Chart 2. Dicarboxylic Acids and their Salts; Log Kow vs Molecular Weight


65

Chart 3. Example of the effects of chain length and branching on solubility. Log Kow vs Molecular Weight


66

TABLES

Table 1. Definitions, functions and structures of dicarboxylic acid, salt and ester ingredients in this safety assessment

Ingredient CAS No. Definition Function(s) Formula/structure

Dicarboxylic Acids and Metal Salts Malonic Acid 141-82-2

Malonic Acid is the organic compound that conforms to noted structure.

Fragrance Ingredients; pH Adjusters

Succinic Acid 110-15-6

Succinic Acid is the dicarboxylic acid that conforms to noted structure.


Sodium Succinate 2922-54-5

Sodium Succinate is the sodium salt of succinic acid.

Buffering Agents; pH Adjusters

Disodium Succinate 150-90-3

Disodium Succinate is the disodium salt of Succinic Acid .

Fragrance Ingredients; Not Reported

Glutaric Acid 110-94-1

Glutaric Acid is the organic compound that conforms to noted structure.


Adipic Acid 124-04-9

Adipic Acid is the organic dicarboxylic acid that conforms to noted structure.


Azelaic Acid 123-99-9

Azelaic Acid is the dicarboxylic acid that conforms to noted structure.


Disodium Azelate 17265-13-3

Disodium Azelate is the disodium salt of azelaic acid.

Not Reported

Dipotassium Azelate 19619-43-3

Dipotassium Azelate is the organic salt that conforms to noted structure.

Not Reported

Sebacic Acid 111-20-6

Sebacic Acid is the organic dicarboxylic acid that conforms to noted structure.

pH Adjusters

Disodium Sebacate 17265-14-4

Disodium Sebacate is the disodium salt of Sebacic Acid . It conforms to the noted structure.

Not Reported

Dodecanedioic Acid 693-23-2

Dodecanedioic Acid is the organic compound that conforms to noted structure.

Skin-Conditioning Agents - Miscellaneous

Malonic Diester Ingredient Diethyl Malonate 105-53-3

Diethyl Malonate is the organic compound that conforms to noted structure.

Fragrance Ingredients

Succinic Ester Ingredients Monoester Decyl Succinate 54482-22-3 (wrong CAS No. 2530-33-8)

Decyl Succinate is the monoester of decyl alcohol and succinic acid.

Skin-Conditioning Agents - Emollient

Diesters Dimethyl Succinate 106-65-0

Dimethyl Succinate is the diester of methyl alcohol and Succinic Acid.

Nail Polish and Enamel Removers


67


Ingredient CAS No. Definition Function(s) Formula/structure Diethyl Succinate 123-25-1

Diethyl Succinate is the diester of ethyl alcohol and Succinic Acid .

Fragrance Ingredients; Plasticizers; Solvents

Dicapryl Succinate 14491-66-8

Dicapryl Succinate is the organic compound that conforms to noted structure.

Film Formers; Hair Conditioning Agents; Nail Conditioning Agents; Plasticizers; Skin-Conditioning Agents - Emollient

Dicetearyl Succinate 93280-98-9

Dicetearyl Succinate is the diester of Cetearyl Alcohol and Succinic Acid .


wherein n=15 or 17

Branched Diisobutyl Succinate 925-06-4

Diisobutyl Succinate is the organic compound that conforms to the noted structure.

Plasticizers

Diethylhexyl Succinate 2915-57-3

Diethylhexyl Succinate is the diester of 2-ethylhexyl alcohol and Succinic Acid.

Plasticizers; Skin-Conditioning Agents - Emollient; Solvents

Glutaric Ester Ingredients Dimethyl Glutarate 1119-40-0

Dimethyl Glutarate is the diester of methyl alcohol and glutaric acid.

Nail Polish and Enamel Removers

Branched Diisobutyl Glutarate 71195-64-7

Diisobutyl Glutarate is the organic compound that conforms to noted structure.

Plasticizers

Diisostearyl Glutarate No CAS No.

Diisostearyl Glutarate is the diester of isostearyl alcohol and glutaric acid.


One example of an “iso”

Adipic Ester Ingredients Dimethyl Adipate 627-93-0

Dimethyl Adipate is the diester of methyl alcohol and Adipic Acid.


Diethyl Adipate 141-28-6

Diethyl Adipate is the diester of ethyl alcohol and adipic acid.

Fragrance Ingredients; Skin-Conditioning Agents - Emollient

Dipropyl Adipate 106-19-4

Dipropyl Adipate is the diester of propyl alcohol and adipic acid.

Skin-Conditioning Agents - Emollient; Solvents


68


Ingredient CAS No. Definition Function(s) Formula/structure Dibutyl Adipate 105-99-7

Dibutyl Adipate is the diester of butyl alcohol and adipic acid.

Nail Polish and Enamels; Suntan Gels, Creams, and Liquids

Dihexyl Adipate 110-33-8

Dihexyl Adipate is the diester of hexyl alcohol and adipic acid.


Dicapryl Adipate 105-97-5

Dicapryl Adipate is the diester of capryl alcohol and adipic acid.

Plasticizers

Di-C12-15 Alkyl Adipate No CAS No.

Di-C12-15 Alkyl Adipate is the diester of C12-15 Alcohols and adipic acid.


wherein n=11, 12, 13 or 14

Ditridecyl Adipate 16958-92-2

Ditridecyl Adipate is the diester of Tridecyl Alcohol and Adipic Acid.


Dicetyl Adipate 26720-21-8

Dicetyl Adipate is the diester of cetyl alcohol and adipic acid.


Branched Diisopropyl Adipate 6938-94-9

Diisopropyl Adipate is the diester of isopropyl alcohol and Adipic Acid.

Fragrance Ingredients; Plasticizers; Skin-Conditioning Agents - Emollient; Solvents

Diisobutyl Adipate 141-04-8

Diisobutyl Adipate is the diester of isobutyl alcohol and Adipic Acid.


Diethylhexyl Adipate 103-23-1

Diethylhexyl Adipate is the diester of a 2-ethylhexyl alcohol and Adipic Acid.


Diisooctyl Adipate 108-63-4

Diisooctyl Adipate is the organic compound that conforms to noted structure.



Diisononyl Adipate 33703-08-1

Diisononyl Adipate is the diester of isononyl alcohol and Adipic Acid.




69


Ingredient CAS No. Definition Function(s) Formula/structure Diisodecyl Adipate 27178-16-1

Diisodecyl Adipate is the diester of isodecyl alcohol and Adipic Acid.



Dihexyldecyl Adipate 57533-90-1

Dihexyldecyl Adipate is the diester of Hexyldecanol and Adipic Acid.


Diheptylundecyl Adipate 155613-91-5

Diheptylundecyl Adipate is the diester of adipic acid and heptylundecanol.


Dioctyldodecyl Adipate 85117-94-8

Dioctyldodecyl Adipate is the diester of Octyldodecanol and Adipic Acid .

Plasticizers; Skin-Conditioning Agents - Emollient

Diisocetyl Adipate 59686-69-0 sec: 58262-41-2

Diisocetyl Adipate is the diester of hexadecyl alcohol and Adipic Acid .



Diisostearyl Adipate 62479-36-1

Diisostearyl Adipate is the diester of Isostearyl Alcohol and Adipic Acid.

Plasticizers; Skin-Conditioning Agents - Emollient


Sebacic Ester Ingredients Diethyl Sebacate 110-40-7

Diethyl Sebacate is the diester of ethyl alcohol and Sebacic Acid


Dibutyl Sebacate 109-43-3

Dibutyl Sebacate is the diester of butyl alcohol and sebacic acid.


Dicaprylyl/ Capryl Sebacate No CAS. No.

Dicaprylyl/Capryl Sebacate is the organic compound that conforms generally to the noted structure.


wherein n=7 or 9

Branched Monoester Isostearyl Sebacate 478273-24-4

Isostearyl Sebacate is the half-ester of isostearyl alcohol and sebacic acid.




70


Ingredient CAS No. Definition Function(s) Formula/structure

Branched Disesters Diisopropyl Sebacate 7491-02-3

Diisopropyl Sebacate is the diester of isopropyl alcohol and Sebacic Acid.


Diethylhexyl Sebacate 122-62-3

Diethylhexyl Sebacate is the diester of 2-ethylhexyl alcohol and Sebacic Acid.

Fragrance Ingredients; Plasticizers; Solvents

Dibutyloctyl Sebacate 184706-97-6

Dibutyloctyl Sebacate is the diester of butyloctyl alcohol and sebacic acid.


Diisooctyl Sebacate 10340-41-7

Diisooctyl Sebacate is the organic compound that conforms to noted structure.

Antioxidants; Plasticizers; Skin-Conditioning Agents - Emollient


Dihexyldecyl Sebacate 359073-59-9

Dihexyldecyl Sebacate is the diester of hexyldecyl alcohol and sebacic acid.


Dioctyldodecyl Sebacate 69275-01-0

Dioctyldodecyl Sebacate is the diester of octyldodecanol and sebacic acid.


Diisostearyl Sebacate No CAS No.

Diisostearyl Sebacate is the diester of isostearyl alcohol and sebacic acid.



Dodecanoic Ester Ingredients Dioctyldodecyl Dodecanedioate 129423-55-8

Dioctyldodecyl Dodecanedioate is the diester of octyldodecanol and dodecanedioic acid.

Hair Conditioning Agents; Skin-Conditioning Agents - Miscellaneous

Diisocetyl Dodecanedioate 131252-83-0

Diisocetyl Dodecanedioate is the organic compound that conforms to noted structure.

Skin-Conditioning Agents - Emollient; Surfactants - Emulsifying Agents



71

Table 2a. Physical and Chemical properties of the alkyl dicarboxylic acid and salt ingredients.

INCI Name Malonic Acid Succinic Acid

Sodium Succinate

Disodium Succinate

Glutaric Acid Adipic Acid

Appearance small crystals colorless prisms

crystalline crystalline large monoclinic

prisms

white, monoclinic prisms

Molecular Weight (g/mol)

104.06 118.09 140.07 162.05 132.11 146.14

Melting/Boiling Point (°C)

135 (dec.)/ 264 (est.)

185-187/ 235 206 (est.)/ 486 (est.)

156 (est.)/ 426 (est.)

97.5-98/ 302-304

152/265

Density (g/cm3) 1.63 1.56 -- -- 1.429 1.360

Vapor pressure (mm Hg @ 25°C)

0.001 (est.) 0.0000002 7.3 E-10 (est.) 8.7 E-8 (est.) 0.000003 0.07

Solubility (g/L water @ 25°C)

1520 83 1000 (est.) 31 (est.) 639 30

Log Kow -0.81 -0.59 -3.98 (est.) -3.98 (est.) -0.29 0.08

INCI Name Azelaic Acid Disodium Azelate

Dipotassium Azelate

Sebacic Acid Disodium Sebacate

Dodecanedioic Acid

Appearance monoclinic prismatic needles

crystalline crystalline Monoclinic prismatic

tablets

crystalline --


188.22 238.18 264.40 202.25 246.21 230.31


106.5/ 286.5

186 (est.)/ 484 (est.)

186 (est.)/ 484 (est.)

134.5/ 294.5

194/496 (est.) 128/383 (est.)

Density (g/cm3) 1.0291 -- -- 1.207 -- 1.16


0.00002 (est.) 1.4 E-9 (est.) 1.4 E-9 (est.) 0.000007 (est.)

5.9 E-10 (est.) 0.000002 (est.)


2.4 1000 (est.) 1000 (est.) 1.0 1000 (est.) 0.040

Log Kow 1.57 -3.56 (est.) -3.56 (est.) 2.19 (est.) -3.01 (est.) 3.17 (est.)


Table 2b. Physical and Chemical properties of the mono- and di-carboxylic acid esters.

INCI Name Diethyl Malonate

Decyl Succinate

Dimethyl Succinate

Diethyl Succinate

Dicapryl Succinate

Dicetearyl Succinate

Diisobutyl Succinate

Appearance colorless liquid

-- -- liquid -- -- liquid


160.17 258.35 146.14 174.19 342.51 566-623 230.30


-50/ 198-199

96/377 (est.) 19.5/196.1 -21.3/217.7 14 (est.)/ 375 (est.)

--/-- -48 (est.)/ 216

Density (g/cm3) 1.055 1.002 (est.) 1.1 1.04 0.94 (est.) -- 0.967


0.269 0.000001 (est.)

0.4 (est.) 0.126 0.000008 (est.)

-- 0.019 (est.)


20 20 (est.) 50 (est.) 10 (est.) 0.0015 (est.) -- 0.60 (est.)

Log Kow 0.96 4.57 (est.) 0.26 (est.) 1.28 (est.) 7.39 (est.) -- 3.00 (est.)

INCI Name Diethylhexyl Succinate

Dimethyl Glutarate

Diisobutyl Glutarate

Diisostearyl Glutarate

Dimethyl Adipate

Diethyl Adipate

Dipropyl Adipate

Appearance -- liquid -- -- -- -- --


342.51 160.17 244.33 637.07 174.19 202.25 230.30


-12 (est.)/ 359 (est.)

-42.5/ 214.2 -38 (est.)/ 237

212 (est.)/ 600 (est.)

210/229 (est.)

24-26/ 248-249

-15.7/ 274 (est.)

Density (g/cm3) 0.933 1.0876 0.97 (est.) -- 1.062 1.08 0.98


0.00002 0.185 (est.) 0.008 (est.) 7.8 E-13 (est.) 0.073 (est.) 0.027 (est.)

0.0055 (est.)


0.002 (est.) 27 (est.) 0.29 (est.) 1.16 E-16 (est.) 14 (est.) 2.8 (est.) 0.62 (est.)

Log Kow 7.08 (est.) 0.57 (est.) 3.44 (est.) 17.5 (est.) 0.95 (est.) 1.97 (est.) 2.99 (est.)

INCI Name Dibutyl Adipate

Dihexyl Adipate

Dicapryl Adipate

Di-C12-15 Alkyl

Adipate

Ditridecyl Adipate

Dicetyl Adipate

Diisopropyl Adipate

Appearance -- liquid -- -- -- -- liquid


258.35 314.46 426.67 482-567 510.83 594.99 230.30


37.5/300 (est.)

-8/351 (est.)

26.5-27.1/ 442 (est.)

--/-- 45.9/503 (est.)

56.5-57/ 559 (est.)

-1.1/253 (est.)

Density (g/cm3) 0.96 0.95 (est.) 0.92 (est.) -- 0.91 (est.) 0.897 (est.) 0.982 (est.)


0.0011 (est.) 0.00004 (est.)

0.00000005 (est.)

-- 3.0 E-10 (est.) 1.5 E-12 (est.) 0.0192 (est.)


0.14 (est.) 0.0082 (est.)

0.000041 (est.)

-- 0.0000011 (est.)

0.00000005 (est.)

0.78 (est.)

Log Kow 4.0 (est.) 6.0 (est.) 10.1 (est.) -- 13.8 (est.) 17 (est.) 2.68 (est.)


73

Table 2b. Physical and Chemical properties of the mono- and di-carboxylic acid esters

INCI Name Diisobutyl Adipate


Diisooctyl Adipate

Diisononyl Adipate

Diisodecyl Adipate

Dihexyldecyl Adipate

Appearance liquid liquid -- -- -- --


258.35 370.57 370.57 398.62 426.67 594.99


-20/278-280 -67.8/390 9 (est.)/ 382 (est.)

56 (est.)/ 230 51 (est.)/ 426 (est.)

181 (est.)/ 548 (est.)

Density (g/cm3) 0.95 0.925 0.93 (est.) -- -- 0.896 (est.)


0.0036 (est.) 0.0000009 0.000004 (est.)

3.3 E-6 (est.) 1.9 E-6 (est.)

4.6 E-12 (est.)


0.18 0.00078 0.00067 (est.)

4.0 E-5 (est.) 5.2 E-6 (est.)

0.00000006 (est.)

Log Kow 3.70 (est.) 6.11 7.77 (est.) 9.24 (est.) 10.1 (est.) 16.6 (est.)

INCI Name Diheptylundecyl Adipate

Dioctyldodecyl Adipate

Diisocetyl Adipate


Diethyl Sebacate

Dibutyl Sebacate

Appearance -- -- -- -- liquid liquid


651.10 707.20 594.99 651.10 258.35 314.46


229 (est.)/ 584 (est.)

267 (est.)/ 619 (est.)

181 (est.)/ 565 (est.)

229 (est.)/ 611 (est.)

5/298 -10/ 344-345

Density (g/cm3) 0.892 (est.) 0.888 (est.) 0.896 (est.) -- 0.969 (est.)

0.94


1.26 E-13 (est.) 3.17 E-15 (est.) 1.4 E-11 (est.)

2.4 E-13 (est.) 0.00054 (est.)

0.00004 (est.)


9.8 E-9 (est.) 2.1 E-9 (est.) 4.0 E-12 (est.)

3.6 E-14 (est.) 0.15 (est.) 0.0085 (est.)

Log Kow 18.7 (est.) 20.9 (est.) 16.0 (est.) 17.9 (est.) 3.92 (est.) 5.96 (est.)

INCI Name Dicaprylyl/ capryl Sebacate

Isostearyl Sebacate



Dibutyloctyl Sebacate

Diisooctyl

Sebacate

Appearance -- -- -- -- -- --


426-482 454.73 286.41 426.67 538.89 426.67


--/-- 215 (est.)/ 545 (est.)

-7 (est.)/ 308 (est.)

-48/436 (est.)

135 (est.)/ 510 (est.)

51 (est.)/ 428 (est.)

Density (g/cm3) -- 0.929 (est.) 0.953 (est.) 0.91 0.901 (est.) 0.916 (est.)


-- 2.5 E-13 (est.) 0.0007 (est.)

8.7 E-8 (est.) 1.6 E-10 (est.)

1.6 E-7 (est.)


-- 0.0013 (est.) 0.046 0.00006 (est.) 0.0000006 (est.)

0.00006 (est.)

Log Kow -- 11.2 (est.) 4.63 (est.) 9.72 (est.) 14.1 (est.) 9.72 (est.)


74

Table 2b. Physical and Chemical properties of the mono- and di-carboxylic acid esters

INCI Name Dihexyldecyl Sebacate

Dioctyldodecyl Sebacate

Diisostearyl Sebacate

Dioctyldodecyl Dodecanedioat

e

Diisocetyl Dodecanedioat

e

Appearance -- -- -- -- --


651.10 763.31 707.20 791.36 679.15


229 (est.)/ 584 (est.)

299 (est.)/ 652 (est.)

268 (est.)/ 568 (est.)

314 (est.)/ 668 (est.)

247 (est.)/ 635 (est.)

Density (g/cm3) 0.892 (est.) 0.885 (est.) -- 0.884 (est.) --


1.3 E-13 (est.) 7.4 E-17 (est.) 4.8 E-15 (est.)

1.1 E-17 (est.) 3.6 E-14 (est.)


0.0000001 (est.) 6.8 E-10 (est.) 3.2 E-16 (est.)

3.6 E-10 (est.) 3.4 E-15 (est.)

Log Kow 18.4 (est.) 22.6 (est.) 19.9 (est.) 23.7 (est.) 18.9 (est.)

“(est.)” = estimated value by EPI Suite “(dec.)” = some decomposition occured “--“ = Value not found “E-13” = divided by 1013


Table 3a. Frequency and concentration of use by duration and exposure - Dicarboxylic Acids and Their Salts

2010 Uses22

2010 Conc. of Use (%)35

2010 Uses22 2010 Conc. of

Use (%)35 2010 Uses22

2010 Conc. of Use (%)35

Succinic Acid Sodium Succinate Disodium Succinate

Totals 4 0.001-26 7 NR 45 0.0005-0.4

Duration of Use

Leave-On 2 0.001-0.2 3 NR 38 0.005-0.4

Rinse Off 2 0.001-26 4 NR 7 0.0005

Exposure Type

Eye Area NR NR NR NR 4 NR

Possible Ingestion NR NR NR NR NR NR

Inhalation NR NR NR NR NR NR

Dermal Contact 2 0.01-26 5 NR 40 0.0005-0.4

Deodorant (Underarm) NR NR NR NR NR NR Hair, Non-Coloring 2 0.001-0.2 2 NR 5 NR

Hair, Coloring NR NR NR NR NR NR

Nail NR NR NR NR NR NR

Mucous Membrane NR 0.2 1 NR NR NR

Bath Products NR 26 1 NR NR NR

Baby Products NR NR NR NR NR NR

Adipic Acid Azelaic Acid Sebacic Acid

Totals 25 0.000001-18 9 0.007-10 12 0.0009-1

Duration of Use

Leave-On 2 0.000001 7 0.007-0.3 9 0.0009-0.03

Rinse Off 23 0.5-18 2 10 3 0.001-1

Exposure Type

Eye Area NR 0.000001 NR NR NR NR Possible Ingestion NR 0.000001 NR NR NR NR

Inhalation NR NR NR NR NR NR

Dermal Contact 1 0.000001-18 25 0.007-10 12 0.0009-1

Deodorant (Underarm) NR NR NR NR NR 0.0009

Hair, Non-Coloring 24 0.5 NR NR NR NR

Hair, Coloring NR NR NR NR NR NR

Nail NR NR NR NR NR NR

Mucous Membrane - NR NR NR 1 0.04

Bath Products 1 15-18 NR NR NR NR

Baby Products NR NR NR NR NR NR NR – not reported to be used


7

6

Tab

le 3

b.

Fre

qu

ency

an

d c

once

ntr

atio

n o

f use

by

du

ratio

n a

nd

exp

osu

re -

Est

ers

of D

ica

rbox

ylic

Aci

ds

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

o

f U

se (

%)35

D

ieth

yl M

alon

ate

Dim

ethy

l Suc

cina

te

Dic

apry

l Suc

cina

te

Die

thyl

hexy

l Suc

cina

te

Dim

ethy

l Glu

tara

te

Dim

ethy

l Adi

pate

Tot

als

NR

0.

004-

0.02

12

0.

002-

5 12

N

R

38

0.02

-6

13

0.5-

15

12

0.2

Dur

atio

n of

Use

Le

ave

-On

N

R

0.0

2

NR

0

.00

2

9

NR

3

4

0.0

2-6

N

R

NR

N

R

NR

Rin

se O

ff

NR

0

.00

4-0

.01

1

2

0.2

-5

NR

N

R

4

3-5

1

3

0.5

-15

1

2

0.2

Exp

osur

e T

ype

Eye

Are

a

NR

N

R

NR

0

.00

2

NR

N

R

1

NR

N

R

NR

N

R

NR

Pos

sib

le In

gest

ion

N

R

NR

N

R

NR

N

R

NR

N

R

3

NR

N

R

NR

N

R

Inh

ala

tion

N

R

NR

N

R

NR

1

N

R

NR

1

N

R

NR

N

R

NR

Der

ma

l Con

tact

N

R

0.0

04

-0.0

2

NR

0

.00

2-5

8

N

R

34

1

-6

NR

1

5

NR

N

R

Deo

dor

an

t (U

nd

era

rm)

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Ha

ir, N

on-C

olor

ing

NR

N

R

NR

N

R

1

NR

4

0

.02

-5

NR

N

R

NR

N

R

Ha

ir, C

olor

ing

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Na

il N

R

NR

1

2

0.2

N

R

NR

N

R

NR

1

3

0.5

1

2

0.2

Mu

cou

s M

emb

ran

e N

R

NR

N

R

NR

2

N

R

1

NR

N

R

NR

N

R

NR

Ba

th P

rod

uct

s N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

Ba

by

Pro

du

cts

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

D

ihex

yl A

dipa

te

Dic

apry

l Adi

pate

D

iisob

utyl

Adi

pate

D

iisod

ecyl

Adi

pate

D

ihep

tylu

ndec

yl A

dipa

te

Dio

ctyl

dode

cyl A

dipa

te

Tot

als

1 3

43

NR

22

0.

001-

3 1

NR

N

R

6 3

NR

Dur

atio

n of

Use

Le

ave

-On

1

N

R

38

N

R

22

0

.00

1-3

1

N

R

NR

6

3

N

R

Rin

se O

ff

NR

3

5

N

R

NR

0

.00

2-0

.5

NR

N

R

NR

N

R

NR

N

R

Exp

osur

e T

ype

Eye

Are

a

NR

3

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

Pos

sib

le In

gest

ion

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

3

N

R

Inh

ala

tion

N

R

NR

1

N

R

5

0.0

5-3

N

R

NR

N

R

NR

N

R

NR

Der

ma

l Con

tact

1

3

4

3

NR

8

0

.00

2-3

1

N

R

NR

6

3

N

R

Deo

dor

an

t (U

nd

era

rm)

NR

N

R

30

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Ha

ir, N

on-C

olor

ing

NR

N

R

NR

N

R

5

0.0

5-0

.2

NR

N

R

NR

N

R

NR

N

R

Ha

ir, C

olor

ing

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Na

il N

R

NR

N

R

NR

9

0

.00

1-0

.7

NR

N

R

NR

N

R

NR

N

R

Mu

cou

s M

emb

ran

e N

R

NR

N

R

NR

N

R

0.0

09

N

R

NR

N

R

NR

N

R

NR

Ba

th P

rod

uct

s N

R

NR

5

N

R

NR

0

.5

NR

N

R

NR

N

R

NR

N

R

Ba

by

Pro

du

cts

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R


7

7

Tab

le 3

b.

Fre

qu

ency

an

d c

once

ntr

atio

n o

f use

by

du

ratio

n a

nd

exp

osu

re -

Est

ers

of D

ica

rbox

ylic

Aci

ds

(con

tinu

ed)

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

20

10

Use

s22

20

10

Co

nc.

of

Use

(%

)35

D

iisos

tear

yl A

dipa

te

Die

thyl

Seb

acat

e D

iisos

tear

yl S

ebac

ate

Diis

opro

pyl S

ebac

ate

Die

thyl

hexy

l Seb

acat

e D

iisoo

ctyl

Seb

acat

e

Tot

als

6 3-

10

NR

1.

5 N

R

0.00

5-0.

7 30

0.

06-1

0 13

0.

5-5

NR

1-

3

Dur

atio

n of

Use

Le

ave

-On

4

1

0

NR

1

.5

NR

0

.00

5-0

.7

29

0

.06

-10

1

3

0.5

-5

NR

1

-3

Rin

se O

ff

2

3

NR

N

R

NR

N

R

1

2

NR

1

N

R

NR

Exp

osur

e T

ype

Eye

Are

a

NR

N

R

NR

N

R

NR

N

R

1

NR

4

N

R

NR

N

R

Pos

sib

le In

gest

ion

4

1

0

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Inh

ala

tion

N

R

NR

N

R

NR

N

R

NR

1

N

R

NR

1

N

R

NR

Der

ma

l Con

tact

6

3

-10

N

R

1.5

N

R

0.0

05

-0.7

2

3

0.0

6-1

0

11

0

.5-5

N

R

1-3

Deo

dor

an

t (U

nd

era

rm)

NR

N

R

NR

N

R

NR

N

R

4

1

NR

0

.5

NR

N

R

Ha

ir, N

on-C

olor

ing

NR

N

R

NR

N

R

NR

N

R

6

8

2

NR

N

R

NR

Ha

ir, C

olor

ing

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Na

il N

R

NR

N

R

NR

N

R

NR

1

0

.08

N

R

NR

N

R

NR

Mu

cou

s M

emb

ran

e N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

Ba

th P

rod

uct

s N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

Ba

by

Pro

du

cts

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

D

ioct

yldo

decy

l Seb

acat

e D

ioct

yldo

decy

l D

odec

aned

ioat

e D

iisoc

etyl

Dod

ecan

edio

ate

Tot

als

NR

3-

8 5

6 2

0.9-

7

Dur

atio

n of

Use

Le

ave

-On

N

R

3-8

5

6

2

0

.9-7

Rin

se O

ff

NR

N

R

NR

N

R

NR

N

R

Exp

osur

e T

ype

Eye

Are

a

NR

N

R

NR

N

R

NR

N

R

Pos

sib

le In

gest

ion

N

R

8

1

6

NR

N

R

Inh

ala

tion

N

R

3-5

2

N

R

NR

0

.9-3

Der

ma

l Con

tact

N

R

3-8

5

6

2

0

.9-7

Deo

dor

an

t (U

nd

era

rm)

NR

N

R

NR

N

R

NR

N

R

Ha

ir, N

on-C

olor

ing

NR

N

R

NR

N

R

NR

N

R

Ha

ir, C

olor

ing

NR

N

R

NR

N

R

NR

N

R

Na

il N

R

NR

N

R

NR

N

R

NR

Mu

cou

s M

emb

ran

e N

R

NR

N

R

NR

N

R

NR

Ba

th P

rod

uct

s N

R

NR

N

R

NR

N

R

NR

Ba

by

Pro

du

cts

NR

N

R

NR

N

R

NR

N

R

NR

- n

ot r

epor

ted

to

be

use

d


7

8

Tab

le 3

c.

Cu

rren

t a

nd

his

toric

al f

req

uen

cy a

nd

con

cen

tra

tion

of u

se a

ccor

din

g to

du

ratio

n a

nd

typ

e of

exp

osu

re

- p

revi

ousl

y re

view

ed e

ster

s

D

i but

yl A

dipa

te

Diis

opro

pyl A

dipa

te

#

of

Use

s C

on

c. o

f U

se (

%)

# o

f U

ses

Co

nc.

of

Use

(%

)

da

ta y

ea

r 1

99

4174

20

025

20

102

2 1

99

6174

20

025

20

103

5 1

98

12 2

00

24 2

01

022

19

812

20

034

20

103

5

Tot

als

1 N

R

6 N

R

5-8

NR

11

2 66

70

≤0.

1-25

0.

01-1

5 0.

005-

8

Du

ratio

n o

f U

se

Le

ave

-On

1

N

R

6

NR

5

-8

NR

9

2

60

6

4 ≤0

.1-2

5

0.0

1-1

5

0.0

05

-8

Rin

se O

ff

NR

N

R

0

NR

N

R

NR

2

0

6

6

≤0

.1-2

6

00

1-8

2

-7

Exp

osu

re T

ype

Eye

Are

a

NR

N

R

2

NR

N

R

NR

2

N

R

2

1-2

5

NR

1

Pos

sib

le In

gest

ion

N

R

NR

N

R

NR

N

R

NR

N

R

NR

1

N

R

NR

N

R

Inh

ala

tion

1

N

R

2

NR

N

R

NR

4

7

33

2

1

0.1

-25

1

-15

0

.00

5-8

Der

ma

l Con

tact

1

N

R

3

NR

8

N

R

10

2

62

5

0

≤0

.1-2

5

0.0

1-1

5

0.0

05-

8

Deo

dor

an

t (u

nd

era

rm)

NR

N

R

NR

N

R

NR

N

R

NR

N

R

6

NR

0

.01

N

R

Ha

ir -

Non

-Col

orin

g N

R

NR

N

R

NR

N

R

NR

1

0

3

17

≤0

.1-5

0

.1-3

0

.5-3

Ha

ir-C

olor

ing

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

Na

il N

R

NR

1

N

R

5

NR

N

R

1

NR

N

R

3

NR

Mu

cou

s M

emb

ran

e N

R

NR

N

R

NR

N

R

NR

1

N

R

NR

0

.1-1

N

R

NR

Ba

th P

rod

uct

s N

R

NR

N

R

NR

N

R

NR

8

6

1

1

-25

5

-8

2

Ba

by

Pro

du

cts

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

NR

N

R

D

ieth

ylhe

xyl A

dipa

te

#

of

Use

s C

on

c. o

f U

se (

%)

da

ta y

ea

r 1

98

12 2

00

24 2

01

022

19

812

20

034

20

103

5

T

otal

s 27

49

48

≤0.

1-25

0.

4-38

0.

6-14

D

ura

tion

of

Use

Le

ave

-On

2

1

44

3

9

≤0

.1-1

0

0.4

-38

0

.9-1

4

Rin

se O

ff

6

5

9

1-2

5

NR

0

.6

Exp

osu

re T

ype

Eye

Are

a

NR

2

3

N

R

0.4

-2

NR

P

ossi

ble

Inge

stio

n

5

1

1

1-5

N

R

NR

In

ha

latio

n

6

5

5

1-5

N

R

NR

D

erm

al C

onta

ct

25

4

7

43

≤0

.1-2

5

0.4

-38

0

.6-1

4

Deo

dor

an

t (u

nd

era

rm)

1

NR

N

R

0.1

-1

8

0.9

H

air

- N

on-C

olor

ing

NR

N

R

1

NR

N

R

NR

H

air-

Col

orin

g N

R

NR

N

R

NR

N

R

NR

N

ail

2

2

4

1-5

N

R

2-3

M

uco

us

Mem

bra

ne

NR

4

1

N

R

NR

N

R

Ba

th P

rod

uct

s 4

N

R

NR

1

0-2

5

NR

N

R

Ba

by

Pro

du

cts

NR

N

R

1

NR

N

R

NR

NR

- n

ot r

epor

ted

to

be

use

d


79

Table 3d. Ingredients not reported to be used Dicarboxylic Acids and Their Salts Malonic Acid Glutaric Acid Disodium Azelate Dipotassium Azelate Disodium Sebacate Dodecanedioic Acid Esters of Dicarboxylic Acids Decyl Succinate Diethyl Succinate Dicetearyl Succinate Diisobutyl Succinate Diisobutyl Glutarate Diisostearyl Glutarate Diethyl Adipate Dipropyl Adipate Di-C 12-15 Alkyl Adipate Ditridecyl Adipate Dicetyl Adipate Diisooctyl Adipate Diisononyl Adipate Dihexyldecyl Adipate Diisocetyl Adipate Dibutyl Sebacate Dicaprylyl/Capryl Sebacate Dibutyloctyl Sebacate Dihexyldecyl Sebacate Diisostearyl Sebacate


80

Table 4. Acute toxicity - Dicarboxylic Acids and Their Salts

Animals No./Gender/Group Dose median lethal dose/conc. Reference ORAL

Succinic Acid rats not specified not specified 2260 mg/kg 175 Sodium Succinate rats 4 males, 4 females 0.5-8 g/kg 8 g/kg 70 Glutaric Acid rats 5/dose, male and female 50% aq. solution 2750 mg/kg 67 Adipic Acid mice 13 males 1500-2500 mg/kg of a 6% suspension in 0.5% methyl

cellulose 1900 mg/kg 45

mice not specified not specified 4175 mg/kg 45 mice not specified not specified 4200 mg/kg 45 rats M/F, no. not specified 20% in corn oil 5050 mg/kg 67 rats 5 or 10 males 100-3000 mg/kg (n=5) or 5000 mg/kg (n=10) adipic

acid in 0.85% saline 940 mg/kg

45

Wistar rats not specified not specified approx. 3600 mg/kg 45 rats 10 males 5000 mg/kg of a 33.3% suspension in 0.85% saline >5000 mg/kg 45 rats 5 males, 5 females 14.7-10,000 mg/kg as a 14.7-50% suspension in

carboxymethyl cellulose (CMC) 5560 mg/kg

45

rats not specified 10,000 mg/kg >10,000 mg/kg 45 rat and rabbit not specified not specified >11,000 mg/kg 45 rabbits not specified 2430 or 4860 mg/kg of a 20% partially neutralized

soln (75% sodium adipate) >2430 and <4860 mg/kg 45

Adipic/Glutaric/Succinic Mixture (percentages not given) rats 10 males 5000-7500 mg/kg aq. 6829 mg/kg 67 Azelaic Acid Wistar rats 6 males 6 females 500-4000 mg/kg ≥4000 mg/kg 71 New Zealand rabbits

6 males 6 females 500-4000 mg/kg ≥4000 mg/kg 71

Disodium Sebacate Wistar rats 4 males, 4 females 0-5000 mg/kg >5000 mg/kg 66 New Zealand rabbits

4 males, 4 females 0-6000 mg/kg >6000 mg/kg 66

Dodecanedioic Acid rats m/f; no. not specified not specified >3000 mg/kg 68

DERMAL Glutaric Acid rabbits 1 rabbit/group; M/F 50% aq. solution >10,000 mg/kg 67 Adipic Acid rabbits 1- 2/group; male and

female 5010 (n=1) or 7940 mg/kg (n=2) 40% adipic acid in corn oil, with occlusion

>7940 mg/kg 45

Adipic/Glutaric/Succinic Mixture (percentages not given) rats not specified not specified >200 mg/kg 67

New Zealand white rabbits

not specified 40% aq. solution; 24 h occlusive exposure >7940 mg/kg 67

Dodecanedioic Acid albino rabbits males; no. not specified not specified >6000 mg/kg 68

INHALATION Adipic Acid rats 20/group; males and

females 5.4 or 7.7 mg/l; head/nose-only exposure; MMAD50 <3.5 µm

>7.7 mg/l 69


81

Table 4. Acute toxicity - Dicarboxylic Acids and Their Salts

Animals No./Gender/Group Dose median lethal dose/conc. Reference Adipic/Glutaric/Succinic Mixture rats 20, gender not specified 4 h exposure' percentages not given >0.03 mg/l 67 rats Crl:Cd/BR; 42 males 5.9 mg/l ; 4 h nose-only xposure; 66.0% dimethyl

glutarate; 16.5% dimethyl succinate; 17.0% dimethyl adipate

anterior and posterio nasal passages were affected; nasal lesions distribut-ed along inspiratory airflow routes; lesions in posterior nasal cavity were less severe

116

PARENTERAL Disodium Succinate mice not specified i.v. 4500 mg/kg 175 Adipic Acid mouse not specified i.p., 0.681-50% solution in 0.5% CMC approx. 170 mg/kg 45 mouse not specified i.p., 600 and 900 mg/kg aq. 600 mg/kg 45 mouse not specified i.p. admin 4000 mg/kg 45 rats 7 males i.p., 200-350 mg/kg 275 mg/kg 45 mouse not specified i.v., 650-700 mg/kg 2% solution 680 mg/kg 45 rabbit not specified i.v., 2430 mg/kg 20% soln, partially neutralized 2430 mg/kg 45

Disodium Azelate rats 6 males, 6 females i.p., 0-1198 mg/kg >1198 mg/kg 71 rabbits 6 males, 6 females i.p., 0-1198 mg/kg >1198 mg/kg 71 Disodium Sebacate Wistar rats 4 males, 4 females i.p., 0-7000 mg/kg 5500 mg/kg; dehydration and ascites

formation was noted 66

New Zealand rabbits

4 males, 4 females i.p., 0-8000 mg/kg 6000 mg/kg; dehydration and ascites formation was noted

66

Wistar rats 10 i.v. , 0-1000 mg/kg 560 mg/kg; dehydration and ascites formation was noted

66

New Zealand rabbits

10 i.v., 0-1800 mg/kg 1400 mg/kg; dehydration and ascites formation was noted

66


8

2

Tab

le 5

. Ocu

lar

Irrit

atio

n -

Dic

arb

oxyl

ic A

cid

an

d T

hei

r E

ster

s

Con

cent

ratio

n A

nim

als

Pro

cedu

re

Res

ults

Ref

eren

ce

Succ

inic

Aci

d n

ot s

pec

ified

not

sp

ecifi

ed

ocu

lar

irrita

tion

stu

dy

(det

ails

not

sp

ecifi

ed)

se

vere

ocu

lar

irrita

nt

67

Glu

tari

c A

cid

not

sp

ecifi

ed

not

sp

ecifi

ed

ocu

lar

irrita

tion

stu

dy

(det

ails

not

sp

ecifi

ed)

m

oder

ate

ocu

lar

irrita

nt

67

Adi

pic

Aci

d

u

nd

ilute

d 2

alb

ino

rab

bits

10

or

57

.1 m

g p

lace

d in

eye

; ey

e of

1 a

nim

al r

inse

d

10

mg:

mild

con

jun

ctiv

al i

rrita

tion

in t

he

rinse

d a

nd

un

rinse

d e

yes;

th

e rin

sed

eye

wa

s n

orm

al a

t 3

da

ys a

nd

th

e u

nrin

sed

eye

wa

s n

orm

al a

t 1

4

da

ys;

57

.1 m

g: m

ild c

onju

nct

iva

l irr

itatio

n w

ith t

ran

sien

t co

rnea

l op

aci

ty

in t

he

rinse

d e

ye;

the

eye

wa

s n

orm

al b

y d

ay

3;

mod

era

te t

o m

ild

con

jun

ctiv

al i

rrita

tion

with

mild

cor

nea

l op

aci

ty a

nd

iriti

c ef

fect

s in

th

e u

nrin

sed

eye

; th

e ey

e w

as

nor

ma

l at

da

y 7

67

un

dilu

ted

6 r

ab

bits

; ge

nd

er n

ot s

pec

ified

0.1

ml i

nst

illed

into

th

e ey

e; e

yes

wer

e n

ot r

inse

d

seve

rely

irrit

atin

g -

prim

ary

irrit

atio

n in

dex

of 4

1.5

/11

0;

irrita

ted

co

nju

nct

iva

an

d s

car

form

atio

n,

incr

ease

d c

orn

eal o

pa

city

an

d ir

ida

l in

flam

ma

tion

; n

ot c

lea

red

by

da

y 8

151

un

dilu

ted

3 r

ab

bits

; ge

nd

er n

ot s

pec

ified

10

0m

g in

still

ed fo

llow

ing

GLP

; a

cute

eye

irr

itatio

n/c

orro

sion

tes

t se

vere

irrit

atio

n;

corn

eal o

pa

city

an

d ir

ida

l irr

itatio

n;

clea

red

with

in 1

6

da

ys

151

un

dilu

ted

2 r

ab

bits

; ge

nd

er n

ot s

pec

ified

50

mg

pla

ced

in e

ye;

eyes

wer

e n

ot r

inse

d

seve

rely

irrit

atin

g; c

orn

eal o

pa

city

stil

l pre

sen

t a

t d

ay

8

151

Dod

ecan

edio

ic A

cid

not

sp

ecifi

ed

ma

le r

ab

bits

, n

o. n

ot s

pec

ified

ocu

lar

irrita

tion

stu

dy

(GLP

; d

eta

ils n

ot p

rovi

ded

)

slig

ht

irrita

nt;

irrit

atio

n in

dex

11

.96

/11

0 68

n

ot s

pec

ified

rab

bits

; n

o./g

end

er n

ot s

pec

ified

ocu

lar

irrita

tion

stu

dy

(det

ails

not

pro

vid

ed)

sm

all

are

a o

f cor

nea

l op

aci

ty a

nd

mild

con

jun

ctiv

al i

rrita

tion

; cl

eare

d

with

in 7

da

ys

68


8

3

Tab

le 6

. Der

ma

l irr

itatio

n a

nd

sen

sitiz

atio

n -

Dic

arb

oxyl

ic A

cid

s a

nd

Th

eir

Sa

lts

Dos

e/C

onc.

. A

nim

als

Pro

cedu

re

Res

ults

Ref

eren

ce

IRR

ITA

TIO

N

Succ

inic

Aci

d n

ot s

pec

ified

rab

bits

, n

o./g

end

er n

ot s

pec

ified

irrita

tion

stu

die

s (d

eta

ils n

ot p

rovi

ded

)

slig

ht

to m

ild ir

rita

tion

67

Glu

tari

c A

cid

not

sp

ecifi

ed

rab

bits

, n

o./g

end

er n

ot s

pec

ified

irrita

tion

stu

die

s (d

eta

ils n

ot p

rovi

ded

)

slig

ht

irrita

tion

67

Adi

pic

Aci

d

5

00

mg

of 5

0%

aq

. 6

ra

bb

its

occl

usi

ve a

pp

lica

tion

to

a 5

cm

x 5

cm

are

a o

f a

bra

ded

or

inta

ct s

kin

for

24

h in

tact

ski

n: e

ryth

ema

(sc

ore

2-3

/4),

cle

are

d b

y d

ay

3;

ab

rad

ed s

kin

: mild

to

sev

ere

eryt

hem

a a

nd

ed

ema

(2

/4 a

t 2

4 h

; 0

-2 a

t 7

2 h

), c

lea

red

by

da

y 7

45

un

dilu

ted

or

80

% a

q.

pa

ste

2 r

ab

bits

/gro

up

occl

usi

ve a

pp

lica

tion

to

inta

ct s

kin

on

th

e b

ack

a

nd

th

e ea

r fo

r 2

0 h

no

irrita

tion

on

th

e b

ack

; er

yth

ema

on

th

e ea

r a

t 2

4 h

(sc

ore

of 2

/4),

with

cl

earin

g b

y 7

2 h

45

not

sp

ecifi

ed

rab

bits

, n

o./g

end

er n

ot s

pec

ified

occl

usi

ve a

pp

lica

tion

for

24

h n

ot ir

rita

ting

45

un

dilu

ted

or

50

% p

ast

e in

p

rop y

len

e gl

ycol

(P

G)

6 r

ab

bits

sem

i-occ

lusi

ve a

pp

lica

tion

of 5

00

mg

for

24

h

sl

igh

t to

mild

irrit

atio

n in

3/6

ra

bb

its w

ith 5

0%

; n

o co

rros

ion

with

u

nd

ilute

d t

est

ma

teria

l 45

50

% in

PG

10

gu

inea

pig

s, g

end

er n

ot

spec

ified

a

pp

lied

to

inta

ct s

kin

no

irrita

tion

45

Succ

inic

/Glu

tari

c/A

dipi

c A

cids

Mix

ture

(pe

rcen

tage

s no

t spe

cifi

ed)

not

giv

en

guin

ea p

igs,

no.

/gen

der

not

sp

ecifi

ed

irrita

tion

stu

dy

(det

ails

not

pro

vid

ed)

n

o to

mild

irrit

atio

n 69

Dod

ecan

edio

ic A

cid

not

sp

ecifi

ed

ma

le r

ab

bits

, n

o. n

ot s

pec

ified

irrita

tion

stu

dy;

4 h

exp

osu

re (

GLP

; d

eta

ils n

ot

pro

vid

ed)

not

an

irrit

an

t; ir

rita

tion

ind

ex 0

/8 68

0.5

g

ma

le r

ab

bits

, n

o. n

ot s

pec

ified

FH

SA

pro

ced

ure

s n

ot a

n ir

rita

nt

68

SE

NS

ITIZ

AT

ION

A

dipi

c A

cid

ind

uct

ion

: 0.1

ml o

f 1.0

%

aq

. so

ln;

cha

llen

ge: 0

.05

m

l of 5

0 a

nd

25

% in

PG

10

gu

inea

pig

s/gr

oup

ind

uct

ion

: 4 s

acr

al i

ntr

ad

erm

al i

nje

ctio

ns,

1

/wk;

ch

alle

nge

: der

ma

l ap

plic

atio

n a

fter

a 2

w

k re

st p

erio

d

very

mild

to

no

irrita

tion

; n

o se

nsi

tiza

tion

45

Succ

inic

/Glu

tari

c/A

dipi

c A

cids

Mix

ture

(pe

rcen

tage

s no

t spe

cifi

ed)

not

giv

en

guin

ea p

igs,

no.

/gen

der

not

sp

ecifi

ed

sen

sitiz

atio

n s

tud

y (d

eta

ils n

ot p

rovi

ded

)

not

a s

ensi

tizer

69

Dod

ecan

edio

ic A

cid

ind

uct

ion

: 0.5

%;

cha

llen

ge: 2

5 a

nd

50

% fe

ma

le g

uin

ea p

igs,

no.

not

sp

ecifi

ed

Ma

gnu

sson

-Klig

ma

n m

axi

miz

atio

n t

est

(intr

acu

tan

eou

s a

dm

in a

t in

du

ctio

n;

der

ma

l a

dm

in a

t ch

alle

nge

)

not

a s

ensi

tizer

68


8

4

Tab

le 7

. Gen

otox

icity

stu

die

s -

Dic

arb

oxyl

ic a

cid

s a

nd

Th

eir

Sa

lts

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

IN V

ITR

O

Mal

onic

Aci

d

≤3

33

3 µ

g/p

late

wa

ter

NT

P p

rein

cub

atio

n a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

S.

typ

him

uri

um

TA

10

0,

TA

15

35

, T

A9

7,

TA

98

n

ega

tive

75

Succ

inic

Aci

d

≤5

mg/

pla

te p

hos

ph

ate

bu

ffer

Am

es t

est

S.

typ

him

uri

um T

A9

2,

TA

15

35

, T

A1

00

, T

A1

53

7,

TA

94

, T

A9

8 n

ega

tive

76

≤1

.0 m

g/m

l sa

line

chro

mos

oma

l ab

erra

tion

ass

ay

C

hin

ese

ha

mst

er fi

bro

bla

sts

cells

neg

ativ

e 76

S

od

ium

Su

ccin

ate

≤1

0 µ

g/p

late

dis

tille

d w

ate

r A

mes

tes

t, +

/- m

eta

bol

ic a

ctiv

atio

n S

. ty

ph

imu

riu

m T

A9

7,

TA

10

2 n

ega

tive

176

Dis

odiu

m S

ucci

nate

≤5

mg/

pla

te p

hos

ph

ate

bu

ffer

Am

es t

est

S.

typ

him

uri

um

TA

92

, T

A1

53

5,

TA

10

0,

TA

15

37

, T

A9

4,

TA

98

n

ega

tive

76

≤1

0,0

00

µg/

pla

te d

istil

led

wa

ter

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A9

7,

TA

10

2 n

ega

tive

175

≤1

5.0

mg/

ml

salin

e ch

rom

osom

al a

ber

ratio

n a

ssa

y

Ch

ines

e h

am

ster

fib

rob

last

s ce

lls eq

uiv

oca

l 76

G

luta

ric

Aci

d

0-5

00

0 µg

/pla

te n

ot s

pec

ified

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um

TA

98

, T

A1

00

, T

A1

53

5,

TA

15

37

, T

A1

53

8 n

ega

tive

67

0-8

29

5 µg

/ml

not

sp

ecifi

ed

mou

se ly

mp

hom

a a

ssa

y,+

/-m

eta

bol

ic a

ctiv

atio

n

L51

78

Y/

TK

cel

ls

neg

ativ

e w

ith

neu

tra

l pH

67

0-1

2.5

mg/

ml w

/ou

t; 0

-2

6.3

mg/

ml w

/met

. a

ct.

DM

SO

tra

nsf

orm

atio

n a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

B

alb

/c-3

T3

cel

ls p

ositi

ve,

+/-

a

ctiv

atio

n 67

≤1

0,0

00

µg/

pla

te w

ate

r N

TP

pre

incu

ba

tion

ass

ay,

+/-

met

ab

olic

act

iva

tion

S

. ty

ph

imu

riu

m T

A1

00

, T

A1

53

5,

TA

97

, T

A9

8

neg

ativ

e 17

7 A

dipi

c A

cid

≤1

0,0

00

µg/

pla

te D

MS

O

NT

P p

rein

cub

atio

n a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

S.

typ

him

uri

um

TA

10

0,

TA

15

35

, T

A9

7,

TA

98

n

ega

tive

79

≤1

0 m

g/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

;

E.

coli

WP

2 n

ega

tive

45

≤5

mg/

pla

te n

ot s

pec

ified

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um

TA

15

35

, T

A1

53

7,

TA

15

38

, T

A9

8,

TA

100;

E.

coli

WP

2u

vrA

neg

ativ

e 45

≤2

00

mg/

l n

ot s

pec

ified

Am

es t

est,

with

out

met

ab

olic

act

iva

tion

S

. ty

ph

imu

riu

m TA

15

30

, G

-46

neg

ativ

e 45

≤2

00

mg/

l n

ot s

pec

ified

yea

st g

ene

mu

tatio

n a

ssa

y, w

ithou

t m

eta

bol

ic a

ctiv

atio

n

S.

cere

visi

ae D

-3

neg

ativ

e 45

≤2

00

0 µ

g/p

late

DM

SO

mou

se ly

mp

hom

a a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

L5

17

8Y

/TK

± c

ells

n

ega

tive

80

≤2

00

mg/

l n

ot s

pec

ified

cyto

gen

etic

ass

ay,

with

out

met

ab

olic

act

iva

tion

h

um

an

em

bry

onic

lun

g fib

rob

last

s

neg

ativ

e 45

≤1

00

0 µ

g/m

l n

ot s

pec

ified

vira

l en

ha

nce

d c

ell t

ran

sfor

ma

tion

ass

ay

S

yria

n h

am

ster

ova

ry c

ells

neg

ativ

e 45

A

dipi

c/G

luta

ric/

Succ

inic

Aci

d M

ixtu

re

0-3

00

0 µ

g/p

late

50

% a

q.

solu

tion

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A9

8,

TA

10

0,

TA

15

35

, T

A 1

53

7,

TA

15

38

neg

ativ

e 67

≤5

00

0 µ

g/m

l n

ot s

pec

ified

un

sch

edu

led

DN

A s

ynth

esis

F3

44

ra

t h

epa

tocy

tes

neg

ativ

e 67

≤2

50

0 µ

g/m

l n

ot s

pec

ified

HG

PR

T a

ssa

y, w

ithou

t m

eta

bol

ic a

ctiv

atio

n

not

sp

ecifi

ed

neg

ativ

e 67

≤3

50

0 µ

g/m

l n

ot s

pec

ified

HG

PR

T a

ssa

y, w

ith m

eta

bol

ic a

ctiv

atio

n

not

sp

ecifi

ed

neg

ativ

e 67

≤1

50

0 µ

g/p

late

dis

tille

d w

ate

r tr

an

sfor

ma

tion

ass

ay,

with

out

met

ab

olic

act

iva

tion

CH

O c

ells

neg

ativ

e 67


8

5

Tab

le 7

. Gen

otox

icity

stu

die

s -

Dic

arb

oxyl

ic a

cid

s a

nd

Th

eir

Sa

lts

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

≤2

50

0 µ

g/p

late

dis

tille

d w

ate

r tr

an

sfor

ma

tion

ass

ay,

with

met

ab

olic

act

iva

tion

C

HO

cel

ls p

ositi

ve a

t 2

00

0 µ

g/m

l 67

Aze

laic

Aci

d

20

%

crea

m A

mes

tes

t; n

o d

eta

ils n

ot s

pec

ified

neg

ativ

e 49

2

0%

cr

eam

HG

RP

T t

est;

no

det

ails

Ch

ines

e h

am

ster

ova

ry c

ells

neg

ativ

e 67

2

0%

cr

eam

hu

ma

n ly

mp

hoc

yte

test

, n

o d

eta

ils h

um

an

lym

ph

ocyt

es n

ega

tive

67

Seba

cic

Aci

d

≤5

00

0 µ

g/p

late

DM

SO

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

;

E.

coli

WP

2 n

ega

tive

178

Dod

ecan

edio

ic A

cid

1

0-5

00

0 µ

g/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

neg

ativ

e 68

IN

VIV

O

Glu

tari

c A

cid

0

, 8

00

mg/

kg

dis

tille

d w

ate

r m

icro

nu

cleu

s a

ssa

y 4

ma

le a

nd

4 fe

ma

le C

D-1

mic

e/gr

oup

n

ega

tive

67

Adi

pic

Aci

d

≤3

75

mg/

kg;

1 o

r 5

dos

es n

ot s

pec

ified

cyto

gen

etic

ass

ay;

an

ima

ls d

osed

ora

lly b

y ga

vage

m

ale

ra

ts n

ega

tive

45

50

00

mg/

kg (

1 d

ose)

; 2

50

0 m

g/kg

(5

dos

es)

not

sp

ecifi

ed

cyto

gen

etic

ass

ay;

an

ima

ls d

osed

ora

lly b

y ga

vage

m

ale

ra

ts n

ega

tive

45

≤3

75

mg/

kg;

1 o

r 5

dos

es n

ot s

pec

ified

dom

ina

nt

leth

al a

ssa

y; a

nim

als

dos

ed o

rally

be

gava

ge

ma

le r

ats

neg

ativ

e 45

50

00

mg/

kg (

1 d

ose)

; 2

50

0 m

g/kg

(5

dos

es)

not

sp

ecifi

ed

dom

ina

nt

leth

al a

ssa

y; a

nim

als

dos

ed o

rally

be

gava

ge

ma

le r

ats

neg

ativ

e 45

Adi

pic/

Glu

tari

c/Su

ccin

ic A

cid

Mix

ture

27

50

mg/

kg (

ma

les)

, 1

37

5 m

g/kg

(fe

ma

les)

not

sp

ecifi

ed

cyto

gen

etic

ass

ay;

an

ima

ls d

osed

ora

lly b

y ga

vage

m

ale

an

d fe

ma

le S

pra

gue

Da

wle

y ra

ts;

1 d

ose

n

ega

tive

67

Aze

laic

Aci

d

20

%

crea

m d

omin

an

t le

tha

l ass

ay

mic

e n

ega

tive

67

Dod

ecan

edio

ic A

cid

≤5

00

0 m

g/kg

not

sp

ecifi

ed

mic

ron

ucl

eus

ass

ay

Crl:

CD

-1(C

R)B

R m

ice

neg

ativ

e 68


8

6

Tab

le 8

. In

du

ctio

n o

f per

oxis

ome

pro

lifer

atio

n –

Est

ers

of D

ica

rbox

ylic

Aci

ds

Tes

t Sys

tem

/Pro

cedu

re

Tes

t Com

poun

d/D

ose

Res

ults

/Obs

erva

tions

R

efer

ence

Die

thyl

hexy

l Adi

pate

h

epa

tocy

tes

from

ma

le S

wis

s m

ice

an

d

rats

d

ieth

ylh

exyl

ad

ipa

te (

DE

HA

) n

o p

erox

isom

e p

rolif

era

tion

C

orn

u e

t a

l. 1

99

2

1

° m

eta

bol

ites:

ME

HA

; 2

-eth

yl-

hex

an

ol,

0.5

mM

5

-fol

d in

du

ctio

n o

f per

oxis

oma

l β-ox

ida

tion

in m

ouse

hep

ato

cyte

s, a

s m

easu

red

by

cya

nid

e-in

sen

si-

tive

pa

lmito

yl C

oA o

xid

ase

(P

CO

) a

ctiv

ity;

4-5

fold

incr

ease

in r

at

hep

ato

cyte

s

2

° m

eta

bol

ite: 2

-eth

ylh

exa

noi

c a

cid

, 1

mM

2

5-f

old

ind

uct

ion

of P

CO

act

ivity

in m

ouse

hep

ato

cyte

s;9

-fol

d in

crea

se in

ra

t h

epa

tocy

tes;

2-e

thyl

-h

exa

noi

c a

cid

wa

s th

e p

roxi

ma

te p

erox

isom

e p

rolif

era

tor

2

° m

eta

bol

ite: 2

-eth

yl-5

-hyd

roxy

-1-

oic

aci

d,

2m

M

5-f

old

stim

ula

tion

of P

CO

cultu

red

gu

inea

pig

hep

ato

cyte

s D

EH

A a

nd

met

ab

olite

s,

≤2

mM

d

id n

ot s

timu

late

PC

O

Cor

nu e

t a

l. 1

99

2

cultu

red

ma

rmos

et h

epa

tocy

tes

DE

HA

an

d m

eta

bol

ites,

≤2

mM

d

id n

ot s

timu

late

PC

O

ma

le a

nd

fem

ale

Wis

tar

rats

an

d S

wis

s m

ice,

5/g

end

er/g

rou

p;

dos

ed o

rally

by

gava

ge fo

r 1

4 d

ays

in c

orn

oil

DE

HA

, 0

-2.5

g/k

g -

rela

tive

liver

to

bod

y w

eigh

ts in

crea

sed

dos

e-d

epen

den

tly

-on

a m

ola

r b

asi

s, D

EH

A w

as

twic

e a

s p

oten

t a

s 2

-eth

ylh

exa

nol

or

2-e

thyl

hex

an

oic

aci

d

-p

erox

isom

al β-

oxid

atio

n w

as

ind

uce

d in

a li

nea

r d

ose-

resp

onse

ma

nn

er;

-P

CO

wa

s st

imu

late

d t

o th

e gr

eate

st e

ffect

in m

ale

mic

e -2

-eth

ylh

exa

noi

c a

cid

wa

s th

e p

rima

ry p

rolif

era

tor

Kei

th e

t a

l. 1

99

2

2-e

thyl

hex

an

ol,

0-1

.75

g/k

g

2-e

thyl

hex

an

oic

aci

d,

0-1

.0 g

/kg

ma

le a

nd

fem

ale

F3

44

ra

ts o

r fe

ma

le

B6

C3

F 1 m

ice,

5/g

end

er/g

rou

p;

dos

ed

ora

lly b

y ga

vage

for

14

da

ys in

cor

n o

il

≤2

.5 g

/kg/

da

y D

EH

A

-PC

O a

ctiv

ity w

as

incr

ease

d t

o th

e gr

ea

test

ext

ent,

15

-fol

d,

in m

ale

ra

ts

-dos

e-re

late

d p

erox

isom

e p

rolif

era

tion

wa

s st

atis

tica

lly s

ign

ifica

ntly

incr

ease

d

in b

oth

ra

t a

nd

mic

e -r

ela

tive

liver

wei

ghts

wer

e in

crea

sed

in a

dos

e-d

epen

den

t m

an

ner

Kei

th e

t a

l. 1

99

2

fem

ale

F3

44

an

d B

6C

3F

1 m

ice,

5-

8/g

rou

p;d

osed

for

1,

4,o

r 1

3 w

ks

0-4

.0%

DE

HA

in t

he

die

t (r

ats

) 0

-2.5

% D

EH

A in

th

e d

iet

(mic

e)

-PC

O in

du

ctio

n w

as

ma

rked

ly in

crea

sed

in r

ats

an

d m

ice

at

all

3 t

ime

fra

mes

-m

icro

som

al c

ytoc

hro

me

act

ivity

an

d s

timu

latio

n o

f rep

lica

tive

DN

A w

as

sign

ifica

ntly

incr

ease

d in

m

ice,

bu

t n

ot in

ra

ts

Lake

et

al.

19

97

ma

le F

34

4 r

ats

an

d fe

ma

le B

6C

3F

1 m

ice,

5/g

rou

p;

5 m

l/kg

for

14

da

ys;

rou

te o

f ad

min

istr

atio

n n

ot s

pec

ified

0-2

g/k

g D

EH

A

-PC

O a

nd

ca

tala

se a

ctiv

ity,

bu

t n

ot g

luta

thio

ne

act

ivity

, w

ere

sta

tistic

ally

sig

nifi

can

tly in

crea

sed

-s

tea

dy-

sta

te h

ydro

gen

per

oxid

e a

ctiv

ity in

crea

sed

2-f

old

com

pa

red

to

con

trol

s T

oma

szew

ski e

t a

l. 1

98

6

F3

44

ra

ts,

3-4

/gro

up

; d

ieta

ry a

dm

ini-

stra

tion

, 3

0 d

ays

0

.25

-2%

DE

HA

0

.25

-2%

die

thyl

hex

yl p

hth

ala

te

0.0

01

-0.0

2%

cip

rofib

rate

(a

ver

y p

oten

t p

erox

isom

e p

rolif

era

tor)

-hep

ato

meg

alic

pot

enci

es o

f die

thyl

hex

yl p

hth

ala

te w

ere

20

0 a

nd

of c

ipro

fibra

te w

ere

10

00

—fo

ld

grea

ter

tha

n D

EH

A

-DE

HA

pro

du

ced

mod

era

te p

erox

isom

e p

rolif

era

tion

at

2%

, b

ut

not

at

low

er c

once

ntr

atio

ns

Red

dy

et a

l., 1

98

6

rats

, 2

ma

les

an

d 2

fem

ale

s/gr

oup

; d

ieta

ry a

dm

inis

tra

tion

, 2

1 d

ays

≤2

.5%

DE

HA

a

t 2

.5%

, p

erox

isom

e p

rolif

era

tion

wa

s m

ark

edl

y in

crea

sed

in

ma

les

an

d m

oder

ate

ly in

crea

sed

in

fem

ale

s; o

vera

ll, h

owev

er,

act

ivity

wa

s w

eak

Ba

rber

et

al.

19

87

Die

thyl

hexy

l Seb

acat

e 4

ma

le F

34

4 r

ats

; d

ieta

ry a

dm

inis

tra

tion

fo

r 3

wks

2

% d

ieth

ylh

exyl

seb

aca

te

hep

atic

per

oxis

ome

pro

lifer

atio

n w

as

obse

rved

, ev

iden

ced

by

incr

ease

d li

ver

size

, h

epa

tic a

ctiv

ities

of

per

oxis

ome-

ass

ocia

ted

en

zym

es,

an

d h

ypol

ipid

emia

M

ood

y et

al.

19

78


87

Table 9. Acute toxicity - Esters of Dicarboxylic Acids Animals No./Gender/Group Dose median lethal dose/concentration, or result Reference

ORAL Diethyl Malonate rats not specified not specified 15,000 mg/kg 14 Dimethyl Malonate

rats not specified not specified >2000 mg/kg 14 Diethyl Succinate

rats not specified not specified 8530 mg/kg 118 Dibutyl Adipate rats not specified 20% dispersion 11,260-12,900 mg/kg 5 rats not specified undiluted 1520 mg/kg 5 rats not specified not specified 1290 mg/kg 104 rats not specified undiluted 12,900 mg/kg 86 Di-C7-9 Branched and Linear Alkyl Esters of Adipic Acid

Sprague-Dawley rats 5-10; males/females 2000-15,800 mg/kg, undiluted >15,800 mg/kg 86 Ditridecyl Adipate

Sherman Wistar rats 5/gender 16,000 mg/kg >16,000 mg/kg 86 Wistar rats 5/gender 15,000 mg/kg >15,000 mg/kg 86 Diisopropyl Adipate

Sprague-Dawley rats 5 males/5 females formulation containing 1.08% 1 female died 2 Sprague-Dawley rats 5 males/5 females formulation containing 1.08% no animals died 2 Sprague-Dawley rats 5 males/5 females formulation containing 5% no animals died 2 2rats 5 males/f5 females formulation containing 0.7% >76,800 mg/kg 2 rats not specified formulation containing 20.75% >15,000 mg/kg 2 Diisobutyl Adipate

NMRI mice 5 males 2000 mg/kg >2000 mg/kg 112 Diethylhexyl Adipate

mice 5 males/5 females ≤20,000 mg/kg in corn oil males: 15,000 mg/kg; females: 24,600 mg/kg 2 rats 5 males/5 females ≤20,000 mg/kg, undiluted 2 males of the 10,000 mg/kg group died; 1 male and

1 female of the 20,000 mg/kg group died 2

albino rats 5 males/5 females 7400 mg/kg 1 animal died 2 rats not specified not specified single oral toxic dose - 9.11 g/kg 2 rats not specified not specified no-effect dose: 6000 mg/kg; central nervous system

effects seen at higher concentrations 2

Harlan-Wistar rats 5 males/5 females formulations containing 0.175% >6500 mg/kg 2 rats not specified not specified 9110 mg/kg 115 rats 5 males/females 7380 mg/kg, undiluted >7300 mg/kg 86 rats not specified not specified 9.1 g/kg 86 Diisooctyl Adipate

rats 5/group 2000-64,000 mg/kg, undiluted >64,000 mg/kg 86 guinea pigs not specified not specified >5 ml/kg 86 Diisononyl Adipate

rats 5/group 0.0346-10 g/kg, undiluted >10,000 mg/kg 86 Diisodecyl Adipate

NMRI mice 5 male 2000 mg/kg >2000 mg/kg 110 rats not specified undiluted 20,500 mg/kg 86 Dioctyldodecyl Adipate

NMRI mice 5 female 2000 mg/kg >2000 mg/kg 111 rats not specified not specified NOAEL <4000 mg/kg 41 Diisocetyl Adipate

NMRI mice 5 males 2000 mg/kg >2000 mg/kg 109 Diisopropyl Sebacate

NMRI mice 5 female 2000 mg/kg >2000 mg/kg 125 Diethylhexyl Sebacate

NMRI mice 5 female 2000 mg/kg >2000 mg/kg 108 mice not specified undiluted 9.5 g/kg 86


88

Table 9. Acute toxicity - Esters of Dicarboxylic Acids Animals No./Gender/Group Dose median lethal dose/concentration, or result Reference rats not specified undiluted 5.0 cc/kg 86 rats not specified undiluted 12.8 g/kg 86 rats not specified undiluted 17 g/kg 86 Dioctyldodecyl Dodecanedioate

Wistar rats 5 male/5 female 5000 mg/kg >5000 mg/kg 122 Diisocetyl Dodecanedioate

Wistar rats 5 male/5 female 5000 mg/kg >5000 mg/kg 106 Esterase Metabolites (summary information/results only provided) Ethylhexyl Alcohol (metabolite of diethylhexyl succinate, diethylhexyl adipate, and diethylhexyl sebacate)

rats 1516-7000 mg/kg 117 mice 2500-3768 mg/kg 117 Hexyl Alcohol (metabolite of dihexyl adipate)

rats 3131-4900 mg/kg 117 mice 103-1950 mg/kg 117 Butyloctanol (metabolite of dibutyloctyl sebacate)

rats 12,900 mg/kg 118 Decyl Alcohol (metabolite of decyl succinate )

rats 9800 mg/kg 118 Isooctyl Alcohol (metabolite of diisooctyl adipate and diisooctyl sebacate)

rats mixture of C7-9 branched alkyl alcohols

>2000 mg/kg 117

Nonyl Alcohol (metabolite of diisononyl adipate) rats mixture of C8-10 branched alkyl

alcohols 3000 mg/kg 117

Isodecyl Alcohol (metabolite of diisodecyl adipate) rats mixture of C9-11 branched alkyl


DERMAL Diethyl Malonate rabbits not specified not specified 16,700 mg/kg 14 Dibutyl Adipate

rabbits not specified 96% 20 ml/kg 5 rats not specified i.m. NOAEL >8000 mg/kg 114 Ditridecyl Adipate

rabbits 3 2000 mg/kg >2000 mg/kg 86 rabbits 10 5000 m/kg to abraded skin; semi-

occlusive >5000 mg/kg

86

Diethylhexyl Adipate rabbits 8 ≤8700 m/kg to abraded skin; occlusive mild irritation; no systemic toxic effects 2

rabbits 1 male/1 female ≤8660 mg/kg for 24 h, occluded, 1 intact and 1 abraded site

>8670 mg/kg 115

Diisononyl Adipate

rabbits 4/group 50-3160 mg/kg to abraded skin >3160 mg/kg 86 Diethylhexyl Sebacate

guinea pigs not specified not specified <10,000 mg/kg 1 Dioctyldodecyl Dodecanedioate

NZW rabbits 5 male/5 female 2000 mg/kg, intact skin, 24 h occlusive >2000 mg/kg 107 Esterase Metabolites (summary information/results only provided) Ethylhexyl Alcohol (metabolite of diethylhexyl succinate, diethylhexyl adipate, and diethylhexyl sebacate)

rats >3000 mg/kg 117 rabbits 1980-2600 mg/kg 117 Hexyl Alcohol (metabolite of dihexyl adipate)

rats 1500 mg/kg 117 rabbits 1500 - >500 mg/kg 117 Butyloctanol (metabolite of dibutyloctyl sebacate)


89

Table 9. Acute toxicity - Esters of Dicarboxylic Acids Animals No./Gender/Group Dose median lethal dose/concentration, or result Reference rabbits 3.36 ml/kg 118 Decyl Alcohol (metabolite of decyl succinate )

rabbits 3.5 ml/kg 118 Isooctyl Alcohol (metabolite of diisooctyl adipate and diisooctyl sebacate)

rats mixture of C7-9 branched alkyl alcohols

>2600 mg/kg 117

Nonyl Alcohol (metabolite of diisononyl adipate) rats mixture of C8-10 branched alkyl


Isodecyl Alcohol (metabolite of diisodecyl adipate) rats mixture of C9-11 branched alkyl

alcohols >2600 mg/kg 117

INHALATION Diethyl Malonate rats not specified concentrated vapors for 8 h no deaths 14 Diethyl Succinate

rats not specified concentrated vapors for 8 h no deaths 118 Dibutyl Adipate

albino rats 6 male flowing stream of saturated air, 8 h no mortality 2 Diethylhexyl Adipate

rats not specified concentrated vapors for 8 h no deaths 118 Diethylhexyl Sebacate

rats not specified 250 mg/m3 for 4 h no effect on lung or liver 1 rats 3 saturated vapor, 6 h no lung toxicity 1 rats 4 940 mg/m3, 7 h 3 rats died, may be attributable to thermal decomp

products 1

guinea pigs 2 940 mg/m3, 7 h no animals died 1 rabbits 4 940 mg/m3, 7 h 2 rabbits died, may be attributable to thermal decomp

products 1

Esterase Metabolites (generally, summary information/results only provided) Ethylhexyl Alcohol (metabolite of diethylhexyl succinate, diethylhexyl adipate, and diethylhexyl sebacate) rats 3 males/3 females vapor conc. of 0.89 mg/l or aerosol/

vapor conc of 5.3 mg/l, 4 h 0.89 mg/l: all animals survived; 5.3 mg/l: all animals died

117

mice, rats, and guinea pigs

10 227 ppm, 6 h all animals survived 117

Hexyl Alcohol (metabolite of dihexyl adipate) rats 21 mg/l, 1 h >21 mg/l 117

Butyloctanol (metabolite of dibutyloctyl sebacate) rats concentrated vapors for 8 h no deaths 118

Decyl Alcohol (metabolite of decyl succinate ) rats concentrated vapors for 8 h no deaths 118

PARENTERAL Dimethyl Adipate Sprague-Dawley rats not specified i.p. 1.8 ml/kg 113 Diethyl Adipate

Sprague-Dawley rats not specified i.p. 2.5 ml/kg 113 Dipropyl Adipate Sprague-Dawley rats not specified i.p. 3.8 ml/kg 113 Dibutyl Adipate

rats not specified i.p. 5.2 ml/kg 5 Diisopropyl Adipate

rats not specified i.v. 640 mg/kg 2 Diethylhexyl Adipate

rats not specified i.v. 900 mg/kg 2 rabbits not specified i.v. 540 mg/kg 2 Sprague-Dawley rats not specified i.p. >50 ml/kg 113


90

Table 10. Ocular Irritation - Esters of Dicarboxylic Acids

Concentration Animals/System Procedure Results Reference Diethyl Malonate

undiluted rabbits, no./gender not

specified 0.1 ml slight to moderate irritation 14

Dimethyl Malonate undiluted rabbits, no./gender not

specified 0.1 ml ,unrinsed slight to moderate irritation; cleared by day 8 14

Dibutyl Adipate undiluted rabbits, no. not specified unrinsed minimally irritating 5

undiluted 2 New Zealand rabbits unrinsed slight irritation 5 0.1% in olive oil rabbits unrinsed non-irritating 5 Diisopropyl Adipate

undiluted 6 albino rabbits 0.1 ml, unrinsed negligible irritation 2 undiluted 6 albino rabbits 0.1 ml, unrinsed non-irritating 2 0.7% in formulation 9 albino rabbits 0.1 mi, undiluted,

rinsed some corneal stippling 2

5% in formulation 6 albino rabbits not specified non-irritating 2 20.75% in formulation 6 albino rabbits not specified non-irritating 2 undiluted 3 albino rabbits 0.1 ml, unrinsed non-irritating 112 Diethylhexyl Adipate

undiluted 6 albino rabbits 0.1 ml, unrinsed non-irritating 2 0.01% in formulation 6 albino rabbits 0.1 ml, unrinsed non-irritating 2 0.175% in formulation 6 albino rabbits 0.1 ml, unrinsed mild transient irritant 2 Diisopropyl Sebacate

6 rabbits 0.1 ml, unrinsed minimally irritating 120 Diethylhexyl Sebacate

1.2% in formulation EpiOcular MTT viability assay

undiluted non-irritating 121

Dioctyldodecyl Dodecanedioate undiluted 6 rabbits 0.1 ml, unrinsed MMTS = 0.0; non-irritating 105

Diisocetyl Dodecanedioate undiluted 6 rabbits 0.1 ml, unrinsed MMTS = 0.0; non-irritating 123

Esterase Metabolites (generally, summary information/results only provided) Ethylhexyl Alcohol (metabolite of diethylhexyl succinate, diethylhexyl adipate, and diethylhexyl sebacate) rabbits 20 µg moderately severe corneal irritation 117

Isopropyl Alcohol (metabolite of diisopropyl adipate and diisopropyl sebacate)

rabbits severely irritating 179 Hexyl Alcohol (metabolite of dihexyl adipate)

rabbits highly irritating 117


9

1

Tab

le 1

1. D

erm

al i

rrita

tion

an

d s

ensi

tiza

tion

- E

ster

s of

Dic

arb

oxyl

ic A

cid

s

Dos

e/C

onc.

Ani

mal

s P

roce

dure

R

esul

ts R

efer

ence

D

ER

MA

L IR

RIT

AT

ION

D

ieth

yl M

alon

ate

not

sp

ecifi

ed

rab

bits

oc

clu

sive

ap

plic

atio

n;

4 h

slig

htly

irrit

atin

g 14

D

ime

thyl

Ma

lon

ate

not

sp

ecifi

ed

rab

bits

se

mi-o

cclu

sive

ap

plic

atio

n;

4 h

not

irrit

atin

g; s

ligh

t er

yth

ema

at

30

-60

min

afte

r p

atc

h r

emov

al

14

D

ibut

yl A

dipa

te

un

dilu

ted

rab

bits

a

pp

lied

to

be

lly P

II o

f 2

/8

5 u

nd

ilute

d 5

alb

ino

ra

bb

its

0.1

ml,

ap

plie

d 8

x in

4 h

mo

de

rate

ery

the

ma

at

24

h

un

dilu

ted

3 r

ab

bits

im

pre

gn

ate

d b

an

ds,

3 d

ap

plic

atio

n,

3 w

ks

mo

de

rate

ery

the

ma

5 u

nd

ilute

d 5

ra

bb

its

imp

reg

na

ted

ba

nd

s, a

pp

lied

2w

/wk

for

6 a

pp

lica

tion

s

no

pro

gre

ssiv

e s

kin

da

ma

ge

5

un

dilu

ted

3 r

ab

bits

0

.02

5 m

l to

inta

ct a

nd

ab

rad

ed

ski

n,

3 a

pp

lica

tion

s a

t 3

h

inte

rva

ls f

or

3 d

ays

ery

the

ma

an

d c

ap

illa

ry in

ject

ion

du

rin

g t

he

stu

dy;

de

squ

am

atio

n w

as

ob

serv

ed

5

10

% in

ace

ton

e 5

ha

irle

ss m

ice

ap

plie

d t

o e

ar,

1x/

da

y, 1

0 d

ays

no

ad

vers

e e

ffe

ct 5

10

% in

ace

ton

e m

ice

ap

plic

atio

n t

o b

ack

s, 2

x/d

ay,

14

da

ys n

o a

dve

rse

eff

ect

5 D

iisop

ropy

l Adi

pate

u

nd

ilute

d 9

alb

ino

ra

bb

its

24

h,

0.1

ml,

occ

lusi

ve P

II o

f 1

.6/4

; m

ild ir

rita

nt

2 u

nd

ilute

d 9

alb

ino

ra

bb

its

24

h,

0.1

ml,

occ

lusi

ve P

II o

f 1

.3/4

; m

ild ir

rita

nt

2 u

nd

ilute

d 9

alb

ino

ra

bb

its

24

h,

0.1

ml,

occ

lusi

ve P

II o

f 0

.06

/4; m

inim

ally

irri

tatin

g 2

5%

in f

orm

ula

tion

9 a

lbin

o r

ab

bits

24

h,

0.1

ml,

occ

lusi

ve P

II o

f 0

.33

; m

inim

ally

irri

tatin

g 2

20

.75

% in

fo

rmu

latio

n 9

alb

ino

ra

bb

its

24

h,

0.1

ml,

occ

lusi

ve P

II o

f 0

.11

; m

inim

ally

irri

tatin

g 2

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n;

4 h

, u

nd

ilute

d

non

-irrit

atin

g 11

2 D

ieth

ylhe

xyl A

dipa

te

un

dilu

ted

6 a

lbin

o r

ab

bits

inta

ct a

nd

ab

rad

ed

ski

n,

0.5

ml,

24

h,

occ

lusi

ve

very

mild

irri

tan

t 2

0.1

75

% in

fo

rmu

latio

n 3

alb

ino

ra

bb

its

4,

0.5

ml a

pp

lica

tion

s ir

rita

tion

ind

ex

of

1.6

/4 2

Diis

odec

yl A

dipa

te

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n,

4 h

, u

nd

ilute

d

non

-irrit

atin

g; s

core

s of

0-1

for

eryt

hem

a a

nd

0 fo

r ed

ema

at

1-7

2 h

; re

vers

ible

11

0 D

ioct

yldo

decy

l Adi

pate

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n,

4 h

, u

nd

ilute

d

non

-irrit

atin

g; s

core

s of

0-1

for

eryt

hem

a a

nd

0 o

r 1

for

edem

a a

t 2

4-7

2 h

; re

vers

ible

111

Diis

ocet

yl A

dipa

te

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n,

4 h

, u

nd

ilute

d

non

-irrit

atin

g; s

core

s of

0-2

for

eryt

hem

a a

nd

0 o

r 1

for

edem

a a

t 1

-72

h;

reve

rsib

le 10

9

Die

thyl

Seb

acat

e

u

nd

ilute

d 8

ra

bb

its

inta

ct a

nd

ab

rad

ed s

kin

, oc

clu

sive

, 0

.3 m

l

PII

of 0

.0

124

30

% in

eth

an

ol 8

ra

bb

its

inta

ct a

nd

ab

rad

ed s

kin

, oc

clu

sive

, 0

.3 m

l

PII

of 0

.3

124


9

2

Tab

le 1

1. D

erm

al i

rrita

tion

an

d s

ensi

tiza

tion

- E

ster

s of

Dic

arb

oxyl

ic A

cid

s

Dos

e/C

onc.

Ani

mal

s P

roce

dure

R

esul

ts R

efer

ence

D

iisop

ropy

l Se

baca

te

u

nd

ilute

d 6

ra

bb

its

inta

ct a

nd

ab

rad

ed s

kin

, oc

clu

sive

, 0

.5 m

l

PII

of 2

.88

; n

ot a

prim

ary

irrit

an

t 12

0

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n,

4 h

, u

nd

ilute

d

non

-irrit

atin

g; s

core

s of

1 fo

r er

yth

ema

, w

ith a

2 a

t 2

4 h

, a

nd

0 o

r 1

for

edem

a

at

1-7

2 h

; re

vers

ible

125

Die

thyl

hexy

l Seb

acat

e

un

dilu

ted

3 a

lbin

o ra

bb

its se

mi-o

cclu

sive

ap

plic

atio

n,

4 h

, u

nd

ilute

d

non

-irrit

atin

g; s

core

s of

1 fo

r er

yth

ema

an

d 0

for

edem

a a

t 1

-72

h;

reve

rsib

le

108

un

dilu

ted

2-4

ra

bb

its

occl

usi

ve a

pp

lica

tion

; 4

8 h

not

irrit

atin

g

Dio

ctyl

dode

cyl D

odec

aned

ioat

e

un

dilu

ted

6 N

ZW

ra

bb

its

occl

usi

ve a

pp

lica

tion

, 2

4 h

, 0

.5 m

l

PII

= 0

; n

ot a

prim

ary

irrit

an

t 18

0 D

iisoc

etyl

Dod

ecan

edio

ate

u

nd

ilute

d 6

NZ

W r

ab

bits

occl

usi

ve a

pp

lica

tion

, 2

4 h

, 0

.5 m

l

PII

= 0

; n

ot a

prim

ary

irrit

an

t 18

1 E

ster

ase

Met

abol

ites

Eth

ylh

exy

l Alc

oh

ol (

me

tab

olit

e o

f d

ieth

ylh

exy

l ad

ipa

te a

nd

die

thyl

he

xyl s

eb

aca

te)

3 m

ale

ra

bb

its oc

clu

sion

, 4

h irr

itatin

g 11

7

rab

bits

oc

clu

sive

, 0

.5 m

l h

igh

ly ir

rita

ting;

not

rev

ersi

ble

117

Ca

pry

lic A

lco

ho

l (m

eta

bo

lite

of

dic

ap

ryl s

ucc

ina

te,

dic

ap

ryl a

dip

ate

, a

nd

dic

ap

ryly

l/ca

pry

l se

ba

cate

)

u

nd

ilute

d ra

bb

its

m

ild ir

rita

tion

182

SE

NS

ITIZ

AT

ION

D

ime

thyl

Ma

lon

ate

not

sp

ecifi

ed

guin

ea p

igs

Bu

ehle

r m

eth

od n

ot s

ensi

tizin

g 14

D

ibut

yl A

dipa

te

25

%

5 g

uin

ea

pig

s m

axi

miz

atio

n t

est

no

t se

nsi

tizin

g 5

Die

thyl

hexy

l Adi

pate

0

.1%

in o

live

oil

10

ma

le g

uin

ea

p

igs

ind

uct

ion

: 1

0 in

ject

ion

s; 2

wk

no

n-t

rea

tme

nt

pd

; ch

alle

ng

e:

0.0

5 m

l in

ject

ion

no

t se

nsi

tizin

g 2

Die

thyl

hexy

l Seb

acat

e

un

dilu

ted

rab

bits

oc

clu

sive

pa

tch

es,

det

ails

not

pro

vid

ed n

o re

act

ion

s 1

Dio

ctyl

dode

cyl D

odec

aned

ioat

e

0.1

ml f

or in

tra

der

m

ind

uct

ion

; 0

.5 m

l top

. in

du

ctio

n /

cha

llen

ge

10

fem

ale

gu

inea

p

igs

ma

xim

iza

tion

tes

t n

ot s

ensi

tizin

g; s

ligh

t er

yth

ema

at

ind

uct

ion

12

6

Est

eras

e M

etab

olite

s

H

exy

l Alc

oh

ol (

me

tab

olit

e o

f d

ihe

xyl a

dip

ate

)

1%

in p

etro

latu

m gu

inea

pig

s m

axi

miz

atio

n t

est

not

sen

sitiz

ing

117


9

3

Tab

le 1

2.

Gen

otox

icity

stu

die

s -

Est

ers

of D

ica

rbox

ylic

Aci

ds

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

IN V

ITR

O

Die

thyl

Mal

onat

e

≤5

00

0 µ

g/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A9

8,

TA

10

0 n

ega

tive

14

≤5

00

0 µ

g/p

late

not

sp

ecifi

ed

cyto

gen

etic

ass

ay,

+/-

met

ab

olic

act

iva

tion

h

um

an

per

iph

era

l lym

ph

ocyt

es n

ega

tive;

cyt

otox

ic a

t 5

00

0 µ

g/p

late

14

Dim

eth

yl M

alo

na

te

≤5

00

0 µ

g/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A9

8,

TA

10

0 n

ega

tive;

cyt

otox

ic a

t ≥10

00

µ

g/p

late

14

Dim

ethy

l Suc

cina

te

2

0,0

00

µg/p

late

DM

SO

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A9

8,

TA

10

0 n

ega

tive

134

≤1

0,0

00

µg/

pla

te w

ate

r N

TP

pre

incu

ba

tion

ass

ay,

+/-

met

ab

olic

act

iva

tion

S

. ty

ph

imu

riu

m T

A1

00

, T

A1

53

5,

TA

97

, T

A9

8

neg

ativ

e 13

5

Dim

ethy

l Glu

tara

te

≤1

0,0

00

µg/

pla

te D

MS

O

NT

P p

rein

cub

atio

n a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

S.

typ

him

uri

um

TA

10

0,

TA

15

35

, T

A9

7,

TA

98

n

ega

tive

136

Dim

ethy

l Adi

pate

≤1

0,0

00

µg/

pla

te D

MS

O

NT

P p

rein

cub

atio

n a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

S.

typ

him

uri

um

TA

10

0,

TA

15

35

, T

A9

7,

TA

98

n

ega

tive

137

Dib

utyl

Adi

pate

≤5

00

0 µ

g/p

late

A

me

s te

st,

+/-

me

tab

olic

act

iva

tion

S.

typ

him

uriu

m T

A9

8,

TA

10

0,

TA

15

35

, T

A1

53

7,

TA

15

38

ne

ga

tive

5

Di-

C7-

9 B

ranc

hed

and

Lin

ear

Alk

yl E

ster

s of

Adi

pic

Aci

d

≤1

0.0

µl/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A9

8,

TA

10

0 n

ega

tive

86

Ditr

ide

cyl A

dip

ate

≤1

0 µ

l/pla

te D

MS

O

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

neg

ativ

e 86

Diis

obut

yl A

dipa

te

≤1

0,0

00

µg/

pla

te D

MS

O

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um

TA

98

, T

A1

00

, T

A1

02

, T

A9

7,

TA

98

, E

. co

li w

p2

neg

ativ

e 18

3

Die

thyl

hexy

l Adi

pate

≤5

mg

/pla

te n

ot

spe

cifie

d A

me

s te

st,

+/-

me

tab

olic

act

iva

tion

S.

typ

him

uri

um

TA

15

35

, T

A1

53

7,

TA

15

38

, T

A9

8,

TA

10

0 n

eg

ativ

e 2

50

00

µg/

pla

te n

ot s

pec

ified

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

neg

ativ

e 14

0

≤0

.01

M

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

umT

A9

8,

TA

10

0 n

ega

tive

139

10

,00

0 µ

g/p

late

DM

SO

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

,. T

A9

8,

TA

10

0 n

ega

tive

138

10

,00

0 µ

g/p

late

95

% e

tha

nol

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

,. T

A9

8,

TA

10

0 n

ega

tive

138

10

,00

0 µ

g/p

late

ace

ton

e N

TP

pre

incu

ba

tion

ass

ay,

+/-

met

ab

olic

act

iva

tion

S

. ty

ph

imu

riu

m T

A1

00

, T

A1

53

5,

TA

97

, T

A9

8

neg

ativ

e 14

1 ≤1

50

µg/

pla

te n

ot s

pec

ified

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A1

53

5,

TA

15

37

, T

A1

53

8,

TA

98

, T

A1

00

neg

ativ

e 86


9

4

Tab

le 1

2.

Gen

otox

icity

stu

die

s -

Est

ers

of D

ica

rbox

ylic

Aci

ds

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

not

sp

ecifi

ed

DM

SO

liqu

id s

usp

ensi

on a

ssa

y

S.

typ

him

uriu

m T

A1

00

neg

ativ

e 14

2 ≤4

00

µg/

ml

not

sp

ecifi

ed

sist

er c

hro

ma

tid e

xch

an

ge a

ssa

y, +

/- m

eta

bol

ic

act

iva

tion

Ch

ines

e h

am

ster

ova

ry c

ells

neg

ativ

e w

/ou

t a

ctiv

atio

n;

equ

ivoc

al

w/a

ctiv

atio

n 14

5

≤2

00

µg/

pla

te,

3 o

r 5

1 h

DM

SO

sist

er c

hro

ma

tid e

xch

an

ge a

ssa

y

fem

ale

F3

44

ra

t h

epa

tocy

tes

n

ega

tive

144

≤4

00

µg/

ml

not

sp

ecifi

ed

chro

mos

oma

l ab

erra

tion

ass

ay,

+/-

met

ab

olic

a

ctiv

atio

n C

hin

ese

ha

mst

er o

vary

cel

ls so

me

evid

ence

w/o

ut

act

iva

tion

; n

ega

tive

w/a

ctiv

atio

n 14

5

≤2

00

µg/

pla

te,

3 o

r 5

1 h

DM

SO

chro

mos

oma

l ab

erra

tion

ass

ay

fe

ma

le F

34

4 r

at

hep

ato

cyte

s

neg

ativ

e 14

4 ≤0

.01

M

not

sp

ecifi

ed

3 H-t

hym

idin

e a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

sple

nic

lym

ph

oid

cel

ls d

ose-

dep

end

ent

inh

ibiti

on o

f 3 H

-th

y-m

idin

e in

to r

eplic

atin

g D

NA

, w

/a

dos

e-d

epen

den

t in

crea

se in

th

e ra

tio

of a

cid

-sol

ub

le t

o D

NA

-inco

rpor

ate

d

3 H-t

hym

idin

e

139

≤1

00

0 µ

g/p

late

fo

rwa

rd m

uta

tion

ass

ay,

+/-

met

ab

olic

act

.

L51

78

Y c

ells

neg

ativ

e 14

3 u

rin

e o

f ra

ts d

ose

d w

ith 2

00

0 m

g/k

g d

ieth

ylh

exy

l ad

ipa

te

corn

oil

Am

es t

est

n

ega

tive

149

Diis

onon

yl A

dipa

te

≤1

00

0 µ

g/p

late

A

mes

tes

t, +

/- m

eta

bol

ic a

ctiv

atio

n S

. ty

ph

imu

riu

m TA

98

, T

A1

00

, T

A1

53

5,

TA

15

37

, T

A1

53

8 n

ega

tive

150

≤1

00

µg/

ml

ly

mp

hom

a a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

mou

se ly

mp

hom

a L

51

78

Y c

ells

neg

ativ

e

≤1

00

0 µ

g/m

l

tra

nsf

orm

atio

n a

ssa

y S

yria

n h

am

ster

em

bry

o ce

lls n

ega

tive

150

≤1

.3 µ

/ml

B

ALB

/3T

3 a

ssa

y

neg

ativ

e 15

0 D

ieth

yl S

ebac

ate

re

vers

ion

ass

ay

E.

coli

Sd

-4-7

3 n

ega

tive

151

Dib

utyl

Seb

acat

e

not

sp

ecifi

ed

not

sp

ecifi

ed

Am

es t

est

S,

typ

him

uri

um T

A9

8,

TA

10

0,

TA

15

35

, T

A1

53

7,

TA

15

38

neg

ativ

e 15

2

≤1

0,0

00

µg/

pla

te D

MS

O &

T

wee

n 8

0 A

mes

tes

t, +

/- m

eta

bol

ic a

ctiv

atio

n S

. ty

ph

imu

riu

m TA

98

, T

A1

00

, T

A1

53

5,

TA

15

37; E

. co

li w

p2

uvr

A n

ega

tive

153

Die

thyl

hexy

l Seb

acat

e

≤1

0,0

00

µg/

pla

te D

MS

O

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um

TA

98

, T

A1

00

, T

A1

53

5,

TA

15

37

n

ega

tive

138

≤5

00

0 µ

g/p

late

DM

SO

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

um T

A9

8,

TA

10

0,

TA

15

35

, T

A1

53

7; E.

coli

wp

2 u

vrA

neg

ativ

e 15

4

Est

eras

e M

etab

olite

s

Eth

ylh

exy

l Alc

oh

ol (

me

tab

olit

e o

f d

ieth

ylh

exy

l su

ccin

ate

, d

ieth

ylh

exy

l ad

ipa

te,

an

d d

ieth

ylh

exy

l se

ba

cate

)

10

,00

0 µ

g/p

late

A

mes

tes

t, +

/- m

eta

bol

ic a

ctiv

atio

n

neg

ativ

e 13

8

A

mes

tes

t

neg

ativ

e 15

0 ≤0

.01

M

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

S.

typ

him

uri

umT

A9

8,

TA

10

0 n

ega

tive

139

≤5

00

0 µ

g/p

late

not

sp

ecifi

ed

Am

es t

est,

+/-

met

ab

olic

act

iva

tion

n

ega

tive

117

0-1

.5 m

M

DM

SO

liqu

id s

usp

ensi

on a

ssa

y

S,.

typ

him

uri

um T

A1

00

neg

ativ

e 14

2 n

ot s

pec

ified

not

sp

ecifi

ed

mou

se ly

mp

hom

a a

ssa

y

n

ega

tive

150


9

5

Tab

le 1

2.

Gen

otox

icity

stu

die

s -

Est

ers

of D

ica

rbox

ylic

Aci

ds

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

not

sp

ecifi

ed

not

sp

ecifi

ed

un

sch

edu

led

DN

A s

ynth

esis

n

ega

tive

150

≤0

.01

M

not

sp

ecifi

ed

3 H-t

hym

idin

e a

ssa

y, +

/- m

eta

bol

ic a

ctiv

atio

n

sple

nic

lym

ph

oid

cel

ls d

ose-

dep

end

ent

inh

ibiti

on o

f 3 H

-th

ymid

ine

into

rep

lica

ting

DN

A,

w/a

d

ose-

dep

end

ent

incr

ease

in t

he

ratio

of

aci

d-s

olu

ble

to

DN

A-in

corp

ora

ted

3 H

-th

ymid

ine

139

10

00

mg/

kg

corn

oil

Am

es t

est

per

form

ed o

n u

rine

from

ra

ts d

osed

or

ally

for

15

da

ys

neg

ativ

e 14

9

ME

HA

(m

eta

bo

lite

of

die

thyl

he

xyl a

dip

ate

)

10

,00

0 µ

g/p

late

A

mes

tes

t, +

/- m

eta

bol

ic a

ctiv

atio

n

neg

ativ

e 13

8 ≤1

00

0 µ

g/p

late

A

mes

tes

t

neg

ativ

e 85

M

on

o-(

2-E

thyl

-5-H

ydro

xyh

exy

l)A

dip

ate

(m

eta

bo

lite

of

die

thyl

he

xyl a

dip

ate

)

≤1

00

0 µ

g/p

late

A

mes

tes

t

neg

ativ

e 85

M

on

o-(

2-E

thyl

-5-O

xoh

exy

l)A

dip

ate

(m

eta

bo

lite

of

die

thyl

he

xyl a

dip

ate

)

≤1

00

0 µ

g/p

late

A

mes

tes

t

neg

ativ

e 85

P

rop

yl a

nd

Iso

pro

pyl

Alc

oh

ol (

me

tab

olit

e o

f d

ipro

pyl

ad

ipa

te,

diis

op

rop

yl a

dip

ate

, a

nd

diis

op

rop

yl s

eb

aca

te)

b

act

eria

l an

d m

am

ma

lian

cel

l ass

ays

neg

ativ

e 17

9 Is

oo

ctyl

Alc

oh

ol (

me

tab

olit

e o

f d

iiso

oct

yl a

dip

ate

an

d d

iiso

oct

yl s

eb

aca

te)

C7

-9 b

ran

ched

alk

yl

alc

ohol

s

ba

cter

ial a

nd

ma

mm

alia

n c

ell a

ssa

ys

n

ega

tive

117

IN V

IVO

D

imet

hyl S

ucci

nate

≥1

25

0 m

g/kg

corn

oil

mic

ron

ucl

eus

test

, i.p

. m

ale

F3

44

ra

ts n

ega

tive

184

Dim

ethy

l Glu

tara

te

≥1

25

0 m

g/kg

corn

oil

mic

ron

ucl

eus

test

, i.p

. m

ale

F3

44

ra

ts n

ega

tive

185

Dib

utyl

Adi

pate

≤2

00

0 m

g/k

g o

live

oil

mo

use

mic

ron

ucl

eu

s te

st m

ice

ne

ga

tive

5 ≥7

24

mg/

kg

corn

oil

mic

ron

ucl

eus

test

, i.p

. m

ale

F3

44

ra

ts n

ega

tive

186

Ditr

idec

yl A

dipa

te

≤2

00

0 m

g/kg

non

e m

icro

nu

cleu

s te

st;

dos

ed d

erm

ally

for

13

wks

gr

oup

s of

10

ma

le a

nd

10

fem

ale

Sp

ragu

e D

aw

ley

rats

n

ega

tive

86

Die

thyl

hexy

l Adi

pate

20

00

mg/

kg

corn

oil

mic

ron

ucl

eus

test

; d

osed

i.p

. fo

r 3

da

ys

5 m

ale

B3

C3

F 1 m

ice

neg

ativ

e 14

6 ≤5

00

0 m

g/kg

corn

oil

chro

mos

oma

l ab

erra

tion

ass

ay

8

ma

le B

3C

3F 1

mic

e n

ega

tive

148

not

sp

ecifi

ed

corn

oil

ch

rom

osom

al a

ber

ratio

n a

ssa

y

8 B

6C

3F 1

mic

e n

ega

tive

147

50

00

mg/

kg

corn

oil

mic

ron

ucl

eus

test

sin

gle

i.p.

dos

e

6 m

ale

/6 fe

ma

le B

3C

3F

1 m

ice

neg

ativ

e 86

D

ibut

yl S

ebac

ate

9

43

-28

29

mg/

kg ol

ive

oil

mic

ron

ucl

eus

test

, i.p

. m

icro

nu

cleu

s te

st n

ega

tive

152

Die

thyl

hexy

l Seb

acat

e

50

0 m

g/kg

n

ot s

pec

ified

rat

liver

foci

tes

t si

ngl

e d

ose

of k

now

n c

arc

inog

en,

the

dos

ing

3x/

wk

for

11

wks

n

o a

ctiv

ity

155


9

6

Tab

le 1

2.

Gen

otox

icity

stu

die

s -

Est

ers

of D

ica

rbox

ylic

Aci

ds

Con

cent

ratio

n V

ehic

le

Pro

cedu

re

Tes

t Sys

tem

Res

ults

Ref

eren

ce

Est

eras

e M

etab

olite

s

Eth

ylh

exy

l Alc

oh

ol (

me

tab

olit

e o

f d

ieth

ylh

exy

l su

ccin

ate

, d

ieth

ylh

exy

l ad

ipa

te,

an

d d

ieth

ylh

exy

l se

ba

cate

)

not

sp

ecifi

ed

not

sp

ecifi

ed

mic

ron

ucl

eus

test

mic

e n

ega

tive

150

not

sp

ecifi

ed

not

sp

ecifi

ed

tra

nsf

orm

atio

n a

ssa

y B

ALB

/3T

3

neg

ativ

e 15

0 P

rop

yl a

nd

Iso

pro

pyl

Alc

oh

ol (

me

tab

olit

e o

f d

ipro

pyl

ad

ipa

te,

diis

op

rop

yl a

dip

ate

, a

nd

diis

op

rop

yl s

eb

aca

te)

C

7-9

bra

nch

ed a

lkyl

a

lcoh

ols

m

icro

nu

cleu

s te

st

neg

ativ

e 17

9


9

7

Tab

le 1

3. C

linic

al d

erm

al i

rrita

tion

an

d s

ensi

tiza

tion

- E

ster

s of

Dic

arb

oxyl

ic A

cid

s

Tes

t Mat

eria

l N

o. o

f Sub

ject

s P

roce

dure

R

esul

ts R

efer

ence

D

ime

thyl

Ma

lon

ate

8%

in p

etro

latu

m 2

5 m

axi

miz

atio

n t

est

not

a s

ensi

tizer

14

Dib

utyl

Adi

pate

u

nd

ilute

d 1

0 2

4 h

pa

tch

te

st n

o ir

rita

tion

at

24

or

48

h 5

20

% in

alc

oh

ol

10

24

h o

cclu

sive

pa

tch

te

st sl

igh

t re

act

ion

s in

4 s

ub

ject

s 5

Diis

opro

pyl A

dipa

te

un

dilu

ted

19

24

h o

cclu

sive

pa

tch

, 0

.1 m

l

no

irri

tatio

n 2

un

dilu

ted

19

24

h o

cclu

sive

pa

tch

, 0

.1 m

l

no

irri

tatio

n 2

un

dilu

ted

15

24

h o

cclu

sive

pa

tch

, 0

.1 m

l

no

irri

tatio

n 2

un

dilu

ted

15

24

h o

cclu

sive

pa

tch

, 0

.1 m

l

no

irri

tatio

n 2

un

dilu

ted

16

cum

ula

tive

irri

tan

cy t

est

mo

de

rate

ly ir

rita

ting

; sc

ore

of

39

5/9

45

; ir

rita

tion

in 1

4/1

6 s

ub

ject

s o

n d

ay

6

2 0

.7%

in f

orm

ula

tion

13

cum

ula

tive

irri

tan

cy t

est

no

n-irr

itatin

g; sc

ore

of

2/6

30

2 1

.1%

in f

orm

ula

tion

17

cum

ula

tive

irri

tan

cy t

est

low

po

ten

tial f

or

ha

zard

to

co

nsu

me

r; s

core

of

0.2

9/8

4

2 1

.1%

in f

orm

ula

tion

17

cum

ula

tive

irri

tan

cy t

est

low

po

ten

tial f

or

ha

zard

to

co

nsu

me

r; s

core

of

0.2

4/8

4

2 2

0.7

5%

in a

ba

th o

il 7

cum

ula

tive

irri

tan

cy t

est

sco

re o

f 8

/84

2 2

0.7

5%

in f

orm

ula

tion

dilu

ted

to

1.2

5%

19

24

h o

cclu

sive

pa

tch

, 0

.1 m

l

min

ima

l irr

itatio

n 2

5.0

% in

fo

rmu

latio

n 1

9 2

4 h

occ

lusi

ve p

atc

h,

0.1

ml

n

o ir

rita

tion

2 1

.08

% in

fo

rmu

latio

n 2

35

HR

IPT

no

se

nsi

tiza

tion

; sl

igh

t h

ype

rpig

me

nta

tion

2

3.0

% in

fo

rmu

latio

n 5

0 H

RIP

T n

o ir

rita

tion

or

sen

sitiz

atio

n 2

5.0

% in

fo

rmu

latio

n 1

08

HR

IPT

no

irri

tatio

n o

r se

nsi

tiza

tion

2 5

.0%

aq

. d

isp

ers

ion

of

a p

rod

uct

co

nta

inin

g 2

0.7

5%

11

6 H

RIP

T m

inim

al,

fain

t e

ryth

em

a p

rod

uce

d t

hro

ug

ho

ut

the

stu

dy

2

0.7

% in

fo

rmu

latio

n 2

5 m

axi

miz

atio

n t

est

no

co

nta

ct s

en

sitiz

atio

n p

ote

ntia

l

2 D

ieth

ylhe

xyl A

dipa

te

0.1

75

% in

fo

rmu

latio

n 1

1 cu

mu

lativ

e ir

rita

ncy

te

st sl

igh

tly ir

rita

ting

; sc

ore

of

72

/63

0 2

0.0

1%

in f

orm

ula

tion

10

0 S

chw

art

z-P

eck

pro

ph

etic

pa

tch

te

st

no

t a

n ir

rita

nt

or

a s

en

sitiz

er

2 0

.01

% in

fo

rmu

latio

n 4

9 S

he

lan

ski a

nd

Sh

ela

nsk

i HR

IPT

w

ea

k re

act

ion

s in

up

to

4 s

ub

ject

s a

nd

str

on

g r

ea

ctio

ns

in 1

su

bje

ct

2 9

.0%

in f

orm

ula

tion

20

9 m

od

ifie

d D

raiz

e-S

he

lan

ski p

atc

h t

est

3

str

on

g r

ea

ctio

ns

an

d 1

fa

int

rea

ctio

n a

t 2

nd

ch

alle

ng

e

2 9

.0%

in f

orm

ula

tion

15

1 m

od

ifie

d D

raiz

e-S

he

lan

ski p

atc

h t

est

ir

rita

nt

rea

ctio

ns

in 2

su

bje

cts;

no

se

nsi

tiza

tion

2

pro

du

ct c

on

tain

ing

0.7

% o

f a

25

%

solu

tion

no

t g

ive

n S

he

lan

ski-Jo

rda

n R

IPT

1-2

su

bje

cts

ha

d r

ea

ctio

ns

du

rin

g t

he

stu

dy

2

Diis

oste

aryl

Adi

pate

u

nd

ilute

d 5

0 H

RIP

T n

ot a

prim

ary

irrit

an

t or

sen

sitiz

er 15

8 1

.5%

in fo

rmu

latio

n 2

0 S

IOP

T n

ot ir

rita

ting

159

1.5

% in

form

ula

tion

25

ma

xim

iza

tion

tes

t n

o co

nta

ct s

ensi

tiza

tion

pot

entia

l

160


9

8

Tab

le 1

3. C

linic

al d

erm

al i

rrita

tion

an

d s

ensi

tiza

tion

- E

ster

s of

Dic

arb

oxyl

ic A

cid

s

Tes

t Mat

eria

l N

o. o

f Sub

ject

s P

roce

dure

R

esul

ts R

efer

ence

D

iisop

ropy

l Seb

acat

e

1

.8%

in fo

rmu

latio

n 2

0 S

IOP

T n

ot ir

rita

ting

161

un

dilu

ted

10

5 p

atc

h t

est

no

irrita

tion

or

sen

sitiz

atio

n 16

2 2

.2%

in fo

rmu

latio

n 2

7 m

axi

miz

atio

n t

est

no

irrita

tion

or

sen

sitiz

atio

n 16

3 1

% in

form

ula

tion

11

0 m

odifi

ed H

RIP

T,

sem

i-occ

lusi

ve n

ot a

n ir

rita

nt

or a

sen

sitiz

er 16

4 1

% in

form

ula

tion

11

0 m

odifi

ed H

RIP

T,

sem

i-occ

lusi

ve n

ot a

n ir

rita

nt

or a

sen

sitiz

er 16

4 7

.2%

in fo

rmu

latio

n 5

1 H

RIP

T,

sem

i-occ

lusi

ve n

o sk

in r

eact

ivity

ob

serv

ed 16

5 D

ieth

yl S

ebac

ate

1.5

% in

form

ula

tion

20

SIO

PT

non

-irrit

atin

g; P

II of

0.0

0 15

9 1

.5%

in fo

rmu

latio

n 2

5 m

axi

miz

atio

n t

est

not

sen

sitiz

ing

161

Die

thyl

hexy

l Seb

acat

e

u

nd

ilute

d 1

5-3

0 oc

clu

sive

pa

tch

es n

o re

act

ion

s 1

Dio

ctyl

dode

cyl D

odec

aned

ioat

e

u

nd

ilute

d 5

0 H

RIP

T n

ot a

prim

ary

irrit

an

t or

sen

sitiz

er 15

8 D

iisoc

etyl

Dod

ecan

edio

ate

un

dilu

ted

50

HR

IPT

not

a p

rima

ry ir

rita

nt

or s

ensi

tizer

158

Est

eras

e M

etab

olite

s

M

eth

an

ol (

me

tab

olit

e o

f d

ime

thyl

su

ccin

ate

, d

ime

thyl

glu

tara

te,

an

d d

ime

thyl

ad

ipa

te

p

rima

ry ir

rita

tion

of t

he

skin

187

3.2

%

27

4 p

rovo

cativ

e oc

cup

atio

na

l stu

dy

p

ositi

ve r

esu

lts 18

7 5

%

cl

osed

pa

tch

tes

t sl

igh

t p

ositi

ve r

eact

ion

(+

) 18

7 7

an

d 7

0%

cl

osed

pa

tch

tes

t +

++

rea

ctio

ns

187

Pro

pyl

Alc

oh

ol

un

dilu

ted

20

24

h p

atc

h t

est

no

rea

ctio

ns

188

un

dilu

ted

11

6 4

8 h

pa

tch

tes

t n

o re

act

ion

s 18

9 u

nd

ilute

d 1

6 2

4 h

pa

tch

tes

t n

o re

act

ion

s 19

0 u

nd

ilute

d 4

2 4

8 h

pa

tch

tes

t n

o re

act

ion

s 19

1 u

nd

ilute

d 1

6 2

4 h

pa

tch

tes

t n

o re

act

ion

s 19

2 u

nd

ilute

d 7

24

h p

atc

h t

est

no

rea

ctio

ns

193

Iso

pro

pyl

Alc

oh

ol (

me

tab

olit

e o

f d

iiso

pro

pyl

alc

oh

ol a

nd

diis

op

rop

yl s

eb

aca

te)

8

0.7

4%

sp

ray

con

cen

tra

tion

9

no

sen

sitiz

atio

n p

oten

tial

19

4 2

.85

% in

form

ula

tion

10

9 H

RIP

T n

o se

nsi

tiza

tion

195

un

dilu

ted

12

24

h p

atc

h t

est

no

rea

ctio

ns

196

Ce

tyl A

lco

ho

l (m

eta

bo

lite

of

dic

ety

l su

ccin

ate

an

d d

ice

tyl a

dip

ate

)

11

.5%

in fo

rmu

latio

n 8

0 to

pic

al t

oler

an

ce s

tud

y re

act

ion

in 1

su

bje

ct 19

7 6

.0%

in fo

rmu

latio

n 1

2 cu

mu

lativ

e irr

itan

cy t

est

mild

cu

mu

lativ

e irr

itatio

n 19

7 8

.4%

in fo

rmu

latio

n 1

10

HR

IPT

not

a p

rima

ry ir

rita

nt

or s

ensi

tizer

197

3.0

% in

form

ula

tion

25

HR

IPT

not

a s

ensi

tizer

197

Myr

isty

l Alc

oh

ol (

me

tab

olit

e o

f d

imyr

isty

l ad

ipa

te)

0.8

0%

in fo

rmu

latio

n 5

3 4

wk

ap

plic

atio

n n

o irr

itatio

n 19

7


9

9

Tab

le 1

3. C

linic

al d

erm

al i

rrita

tion

an

d s

ensi

tiza

tion

- E

ster

s of

Dic

arb

oxyl

ic A

cid

s

Tes

t Mat

eria

l N

o. o

f Sub

ject

s P

roce

dure

R

esul

ts R

efer

ence

0

.25

% in

form

ula

tion

51

4 w

k a

pp

lica

tion

1 r

eact

ion

by

1 s

ub

ject

197

0.2

5%

in fo

rmu

latio

n 2

29

10

- 2

4 h

occ

lusi

ve p

atc

h n

ot a

n ir

rita

nt

or a

n a

llerg

en 19

7 S

tea

ryl A

lco

ho

l ((m

eta

bo

lite

of

dis

tea

ryl s

ucc

ina

te)

un

dilu

ted

S

IOP

T m

ild ir

rita

tion

173

Iso

ste

ary

l Alc

oh

ol (

me

tab

olit

e o

f d

iiso

ste

ary

l glu

tara

te,

diis

ost

ea

ryl a

dip

ate

, o

r d

iiso

ste

ary

l se

ba

cate

)

2

5%

in p

etro

latu

m 1

9

no

irrita

tion

197

25

.0%

in fo

rmu

latio

n

n

o irr

itatio

n 19

7 2

7.0

% in

form

ula

tion

no

irrita

tion

197

28

.0%

in fo

rmu

latio

n

n

o irr

itatio

n 19

7 2

5%

in 9

5%

isop

rop

yl a

lcoh

ol 1

2 H

RIP

T 3

su

bje

ct s

ligh

t er

yth

ema

at

ind

uct

ion

; n

o se

nsi

tiza

tion

19

7 5

% in

form

ula

tion

14

8 H

RIP

T,

with

rec

ha

llen

ge fo

r re

act

ors;

ad

d'l

cha

llen

ge w

ith 5

% in

eth

an

ol 1

2 s

ub

ject

s h

ad

pos

sib

le s

ensi

tiza

tion

rea

ctio

ns

at

1st

ch

alle

nge

; 6

rea

cted

at

rech

alle

nge

; a

ll 6

ha

d p

ositi

ve r

eact

ion

s to

5%

in a

lcoh

ol

197

5%

in fo

rmu

latio

n 6

0 H

RIP

T,

rech

alle

nge

of 5

% in

eth

an

ol fo

r re

act

ors

5 s

ub

ject

s re

act

ed a

t 1

ch

alle

nge

1/5

rec

ha

llen

ged

rea

cted

19

7

Ca

pry

lic A

lco

ho

l (m

eta

bo

lite

of

dic

ap

ryl s

ucc

ina

te,

dic

ap

ryl a

dip

ate

, a

nd

dic

ap

ryly

l/ca

pry

l se

ba

cate

)

2

% in

pet

rola

tum

25

48

h c

lose

d p

atc

h n

o irr

itatio

n 18

2 D

ecy

l Alc

oh

ol (

me

tab

olit

e o

f d

ecy

l su

ccin

ate

an

d d

ide

cyl s

eb

aca

te)

3

% in

pet

rola

tum

25

48

h c

lose

d p

atc

h n

o irr

itatio

n 18

2


1

00

Tab

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101

REFERENCES

1. BIBRA Working Group. 1996. Diethylhexyl Sebacate Toxicity Profile. 6 pages.

2. Elder RL,ed. Final Report on the Safety Assessment of Dioctyl Adipate and Diisopropyl Adipate. J Am Coll Toxicol. 1984;3:(3):101-129.

3. Andersen FA (ed). Annual review of Cosmetic Ingredient Safey Assessments - 2002/2003. Int J Toxicol. 2005;24:(Suppl 1):1-102.

4. Andersen FA (ed). Annual review of Cosmetic Ingredient Safety Assessments - 2004/2005. Int J Toxicol. 2006;25:(Suppl 1):1-89.

5. Andersen FA,ed. Amended final report of the safety assessment of dibutyl adipate as used in cosmetics. Int J Toxicol. 2006;25:(Suppl 1):129-134.

6. Vasihtha, A. K, Trivedi, R. K., and Das, G. Sebacic Acid and 2-Octanol from Castor Oil. Journal of the American Oil Chemists' Society. 1990;67:(5):333-337.

7. Editor: Kroschwitz, J. Concise Encyclopedia od Chemical Technology. 4th ed. 2001.

8. Nghiem NP, Davison BH, and Thomspon JE. Effect of biotin on the production of succinic acid by anaerobiospirillum succinicproducents. Gov't Reports Announcements & Index. Appl.Biochem.Biotechnol. 1995;633:57-58.

9. Kadesch, Richard G. Dibasic Acids. Journal of the American Oil Chemists' Society. 1954;31:568-573.

10. Breathnach, A. S. Azelaic Acid - Biological Activities and Therapeutic Applications. Drugs of Today. 1989;25:(7):463-472.

11. Aditya K.Gupta, Melissa D. Gover. Azelaic acid (15% gel) in the treatment of acne rosacea. International Journal of Dermatology. 2007;46:(5):533-538.

12. Kadesch, Richard G. Dibasic Acids. Journal of the American Oil Chemists' Society. 1954;31:(11):568-573.

13. Ayorinde et al. Synthesis of Dodecanedioic Acid from Vernonia galamensis Oil. Jounal of the American Oil Chemists' Society. 1989;66:(5):690.

14. Organisation for Economic Co-Operation and Development.SIDS Initial Assessment for SIAM 22 -Malonic Acid Diesters, Dimethylmalonate, 108-59-8, and Diethylmalonate, 105-53-3. 2005. http://www.chem.unep.ch/irptc/sids/OECDSIDS/Malonates.pdf. Accessed 7-29-2010.

15. Gattermann, T. Wieland. Praxis des Organischen Chemikers. 40th ed. 1961.

16. Cognis Deutchsland GmbH & Co. 2002. Data Profile: Cetiol® B. 4 pages.

17. International Agency for Research on Cancer (IARC). Di(2-ethylhexyl) adipate. IARC Monographs on the evaluation of the carcinogenic risk of chemicals to humans. 2000;77:149-175.

18. American Chemistry Council Aliphatic Esters Diesters Task Group.High Production Volume (HPV) Chemical Challenge Program test plan for th diesters category of the aliphatic esters chemicals. Dated June 2, 2010. 6-28-2010. http://www.epa.gov/oppt/chemrtk/pubs/summaries/alipestr/c13466rt8.pdf. Accessed 7-8-0010.

19. Kvatadze MK. The gas-chromatographic detection of Sebacic Acid in the air. Gig.Tr.Prof.Zabol. 1989;9:45-46.

20. Hokoku Corporation. Impurity data on diisopropyl sebacate. Unpublished data submitted by the Personal Care Products Council (1 p). 2010.


102

21. Gottschalck TE and Bailey J, eds. International Cosmetic Ingredient Dictionary and Handbook. 2010. 13:(1-3):Washington DC: Personal Care Products Council.2977.

22. Food and Drug Administration.Frequency of use of cosmetic ingredients. 2010.

23. James, A. C., Stahlhofen, W, Rudolf, G, Kobrich, R, Briant, J. K., Egan, M. J., Nixon, W, and Birchall, A. Annexe D. Deposition of inhaled particles. Annals of the ICRP. 1994;24:(1-3):231-2.

24. Oberdorster, G, Oberdorster, E, and Oberdorster, J. Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine Particles. Environmental Health Perspectives. 2005;113:(7):823-839.

25. Bower, D. 1999. Unpublished information on hair spray particle sizes provided at the September 9, 1999 CIR Expert Panel meeting.

26. Johnson, M. A. The Influence of Particle Size. Spray Technology and Marketing. 2004;November:24-27.

27. European Commission.Cosing database on cosmetic ingredient and substances. 2010. http://ec.europa.eu/consumers/cosmetics/cosing/. Accessed 7-27-2010.

28. Dekker. Ingredients. The Chemistry and Manufacture of Cosmetics. 1999. III:(2):


30. The Merck Index. 2009. http://themerckindex.cambridgesoft.com/TheMerckIndex/index.asp. Accessed 10-20-2009.

31. Food and Drug Administration.GRAS status sof succinic acid. 10-31-2006. http://www.accessdata.fda.gov/scripts/fcn/fcnDetailNavigation.cfm?rpt=scogsListing&id=339. Accessed 7-28-2010.

32. Food and Drug Administration.GRAS status of adipic acid. 10-31-2006. http://www.accessdata.fda.gov/scripts/fcn/fcnDetailNavigation.cfm?rpt=scogsListing&id=9.

33. Food and Drug Administration.Azelaic Acid 20% Cream – Drug Approval Label. 1999. http://www.accessdata.fda.gov/drugsatfda_docs/label/2003/20428slr016_azelex_lbl.pdf.

34. Food and Drug Administration.Azelaic Acid 15% Gel – Drug Approval Label. 2003. http://www.accessdata.fda.gov/drugsatfda_docs/label/2005/021470s003lbl.pdf.

35. Personal Care Products Council. Concentration of use of dicarboxylic acids and their salts and esters. 2-25-2010.

36. Jung, H. W., Tschaplinski, T. J., Wang, L., Glazebrook, J., and Greenberg, J. T. Priming in Systemic Plant Immunity. Science. 2009;324:(5923):89-91.

37. Schneider KW. Contact dermatitis due to diethyl sebacate. Cont.Derm. 1980;6:506-507.

38. Shikani AH, Eisele DW, and Domb AJ. Polymer delivery of chemotherapy for squamous cell carcinoma of the head and neck. Arch.Otolaryngol.Head and Neck Surg. 1994;120:1242-1247.

39. Kroha, K. Industrial Biotechnology Provides Opportunities for Commercial Production of New Long-Chain Dibasic Acids. Inform. 2004;15:(9):568-571.

40. Bergman K and Albanus L. Di-(2-ethylhexyl) adipate: absorption, autoradiographic distribution and elimination in mice and rats. Fd Chem Toxicol. 1987;25:(4):309-316.


103

41. Mochida K, Gomyoda M, and Fujita T. Acetyl tributyl citrate and Dibutyl Sebacate inhibit the growth of cultured mammalian cells. Bulletin of Environ.Contamin.and Toxicol. 1996;56:635-637.

42. Greco AV and Mingrone G. Dicarboxylic acids, an alternate fuel substrate in parental nutrition: an update. Clin.Nutr. 1995;14:143-148.

43. Bertuzzi A, Gandolfi A, Salinari S, Mingrone G, and Greco AV. Pharmacokinetics of dicarboxylic acids in man. Engng Med Biol. 1994;13:472-478.

44. Nguyen, Q. H. and Bui, T. P. Azelaic acid: pharmacokinetic and pharmacodynamic properties and its therapeutic role in hyperpigmentary disorders and acne. Int.J.Dermatol. 1995;34:(2):75-84.

45. Organisation for Economic Co-Operation and Development.IUCLID Data Set for Adipic Acid. 2-15-2006. http://www.chem.unep.ch/irptc/sids/OECDSIDS/124049.pdf. Accessed 7-29-2010.

46. Kennedy GL. Toxicity of adipic acid. Drug.Chem.Toxicol. 2002;25:191-202.

47. Passi S, Nazzaro-Porro M, Picardo M, Mingrone G, and Fasella P. Metabolism of straight saturated medium chain length (C9 to C12) dicarboxylic acids. J Lipid Res. 1983;24:1140-1147.

48. Akhavan A and Bershad S. Topical acne drugs: review of clinical properties, systemic exposure, and safety. Am.J.Clin.Dermatol. 2003;4:473-492.

49. Allergan Inc. 2004. Package Insert: AZELEX – Azelaic Acid cream (20%).

50. Passi S. Pharmacology and pharmacokinetics of azelaic acid. (Secondary reference in Breathnach 1999). Rev Comtemp Pharmacother. 1993;4:441-447.

51. Tataranni PA, Mingrone G, DeGaetano A, Raguso C, and Greco AV. Tracer study of metabolism and tissue distributon of sebacic acid in rats. Ann Mutr Metab. 1992;36:296-303.

52. Favuzzi AM, Mingrone G, Bertuzzi A, and et al. Pharmacokinetics of Sebacic Acid in rats. Eur Rev Med Pharmacol Sci. 1999;3:119-125.

53. Mingrone G, Greco AV, Castegneto M, De Gaetano A, Raguso C, and et al. Tissue uptake and oxdation of Disodium Sebacate in man. J.Parenter.Enteral.Nutr. 1991;15:(4):454-459.

54. Greco AV, Mingrone G, Raguso C, and et al. Metabolic effects and disposition of sebacate, an laternate dicarboxylic fuel substrate. Ann.Nutr.Metab. 1992;36:1-11.

55. Mingrone, G., Tacchino, R. M., Castagneto, M., Finotti, E., and Greco, A. V. Use of even-numbered carbon atom dicarboxylic salts in parenteral nutrition as fuel substrate. JPEN J.Parenter.Enteral Nutr. 1992;16:32-38.

56. Mingrone G, Greco AV, Tataranni PA, DeGaetano A, and Castagneto M. Pharmacokinetic profile of dodecanedioic acid, a proposed alternative fuel substrate. JPEN. 1994;18:225-230.

57. Del Rosso, J. Q., Lehman, P. A., and Raney, S. G. Impact of order of application of moisturizers on percutaneous absorption kinetics: evaluation of sequential application of moisturizer lotions and azelaic acid gel 15% using a human skin model. Cutis. 2009;83:119-124.

58. Täuber U, Weiss C, and Matthes H. Percutaneous absorption of azelaic acid in humans. Exp Dermatol. 1992;1:176-179.

59. Moody DE and Reddy, J. K. Hepatic peroxisome (microbody) proliferation in rats fed plasticizers and related compounds. Toxicol Appl Pharmacol. 1978;45:497-504.

60. Robins, E. J., Breathnach, A. S., Ward, B. J., Bhasin, Y. P., Ethridge, L., Nazzaro-Porro, M., Passi, S., and Picardo,


104

M. Effect of dicarboxylic acids on Harding-Passey and Cloudman S91 melanoma cells in tissue culture. J.Invest Dermatol. 1985;85:(3):216-221.

61. Passi S, Picardo M, Mingrone G, Breathnach AS, and Navarro-Porro M.Azelaic Acid - biochemistry and metabolism. 1989.

62. Detmar, M., Mayer-da-Silva, A., Stadler, R., and Orfanos, C. E. Effects of azelaic acid on proliferation and ultrastructure of mouse keratinocytes in vitro. J.Invest Dermatol. 1989;93:(1):70-74.

63. Nazzaro-Porro, M., Passi, S., Zina, G., Bernengo, A., and Breathnach, A. Effect of azelaic acid on human malignant melanoma. Lancet. 1980;1:1109-1111.

64. Breathnach, A. S. Azelaic acid: potential as a general antitumoural agent. Med.Hypotheses. 1999;52:(3):221-226.

65. Melnik BC, Schmitz G, and Zouboulis CC. Anit-acne agents attenuate FGFR2 signal transduction in acne. J Invest Dermatol. 2009;129:1868-1877.

66. Greco AV, Mingrone G, Arcieri Mastromattei E, Finotti E, and Castegneto M. Toxicity of Disodium Sebacate. Drug Exp.Clin.Res. 1990;16:531-536.

67. Environmental Protection Agency.Robust summary for dicarboxylic acid category. 7-10-2001. http://www.epa.gov/HPV/pubs/summaries/dicarbx/c13108.pdf. Accessed 7-19-2010.

68. Organisation for Economic Co-Operation and Development.SIDS report on Dodecanedioic Acid, CAS No. 693-23-2. 1994. http://www.chem.unep.ch/irptc/sids/OECDSIDS/693232.pdf. Accessed 7-29-2010.

69. Organisation for Economic Co-Operation and Development.SIDS Initial Report for SIAM 18 - Adipic Acid, CAS No. 124-04-9. 2004. http://www.chem.unep.ch/irptc/sids/OECDSIDS/124049.pdf. Accessed 7-29-2010.

70. Maekawa, A., Todate, A., Onodera, H., Matsushima, Y., Nagaoka, T., Shibutani, M., Ogasawara, H., Kodama, Y., and Hayashi, Y. Lack of toxicity/carcinogenicity of monosodium succinate in F344 rats. Food Chem.Toxicol. 1990;28:(4):235-241.

71. Mingrone G, Greco AV, Navarro-Porro M, and Passi S. Toxicity of Azelaic Acid. Drugs Exp.Clin.Res. 1983;9:447-455.

72. Fukui S, Shimoyama T, Tamura K, Yamamura M, and Satomi M. Mucosal blood flow and generation of superoxide in rat experimental colitis induced by Succinic Acid. J.Gastroenterol. 1997;32:464-471.

73. Brown-Woodman PD, Post EJ, Chow PY, and White IG. Effects of malonic, citric and caffeic acids on the motility of human sperm and penetration of cervical mucous. Int.J.Fertil. 1985;30:38-44.

74. Mingrone G, Manicelli R, and Metro D. Influence of sodium salts of saturated medium chain length C6, C9, C10 and C12 dicarboxylic acids on the uterine horn of rat in vitro. Q.J.Exp.Physiol. 1988;73:153-162.

75. National Toxicology Program.Salmonella assayon malonic acid. Study ID: 228078. 1989. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=228078&cas%5Fno=141%2D82%2D2&activetab=detail. Accessed 7-26-2010.

76. Ishidate M Jr, Sofuni T, Yoshikawa K, Hayaski M, Nohmi T, Sawada M, and MAtsouka A. Primary mutagenicity screening of food additives currently used in Japan. Food Chem Toxicol. 1984;22:(8):623-636.

77. TOXNET.CCRIS database - Sodium Succinate. CAS No. 2292-54-5. 2-14-1997. Accessed 7-26-2010.

78. Bradford JC, Brown GL, Caldwell JA, and Drobeck HP. Teratology and mutagenicity studies with glutaric acid. Teratol. 1984;29:19A.


105

79. National Toxicology Program.Salmonella assay on adipic acid. Study ID: A86767. 1997. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=A86767&cas%5Fno=124%2D04%2D9&activetab=detail. Accessed 7-26-2010.

80. TOXNET.CCRIS database - Adipic acid. CAS No. 124-04-9. 10-1-2009. http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~vDEUtx:1.

81. Otoshi T, Iwata H, Yamamoto S, Murai T, Yamaguchi S, Matsui-Yuasa I, Otani S, and Fukushima S. Severity of promotion by sodium salts of succinic acid in rat urinary bladder carcinogenesis correlates with sodium ion concentration under conditions of equal urinary pH. Carcinogenesis. 1993;14:(11):2277-2281.

82. Ziel, K., Yelverton, C. B., Balkrishnan, R., and Feldman, S. R. Cumulative irritation potential of metronidazole gel compared to azelaic acid gel after repeated applications to healthy skin. J.Drugs Dermatol. 2005;4:(6):727-731.

83. Feldman, S., Careccia, R. E., Barham, K. L., and Hancox, J. Diagnosis and treatment of acne. Am.Fam.Physician. 2004;69:(9):2123-2130.


85. Dirven, H. A., Theuws, J. L., Jongeneelen, F. J., and Bos, R. P. Non-mutagenicity of 4 metabolites of di(2-ethylhexyl)phthalate (DEHP) and 3 structurally related derivatives of di(2-ethylhexyl)adipate (DEHA) in the Salmonella mutagenicity assay. Mutat.Res. 1991;260:(1):121-130.

86. Environmental Protection Agency.Robust summaries for substances in the HPV test plan for the diesters category of the aliphatic esters chemicals. 6-2-2010. http://www.epa.gov/oppt/chemrtk/pubs/summaries/alipestr/c13466rr8.pdf. Accessed 7-8-2010.

87. Takahashi T, Tanaka A, and Yamaha T. Elimination, distribution, and metabolsim of di-(2-ethylhexyl)adipate (DEHA) in rats. Toxicology. 1981;22:223-233.

88. Cornu, M. C., Keith, Y., Elcombe, C. R., and Lhuguenot, J. C. In vivo and in vitro metabolism of di-(2-ethylhexyl) adipate a peroxisome proliferator, in the rat. Arch.Toxicol. 1988;Suppl 12:265-268.

89. Loftus, N. J., Laird, W. J., Steel, G. T., Wilks, M. F., and Woollen, B. H. Metabolism and pharmacokinetics of deuterium-labelled di-2-(ethylhexyl) adipate (DEHA) in humans. Food Chem.Toxicol. 1993;31:(9):609-614.

90. Cornu, M. C., Lhuguenot, J. C., Brady, A. M., Moore, R., and Elcombe, C. R. Identification of the proximate proliferator(s) derived from di (2-ethylhexyl) adipate and species differences in response. Biochem Pharmacol. 1992;43:(10):2129-2134.

91. Keith, Y., Cornu, M. C., Canning, P. M., Foster, J., Lhuguenot, J. C., and Elcombe, C. R. Peroxisome proliferation due to di (2-ethylhexyl) adipate, 2-ethylhexanol and 2-ethylhexanoic acid. Arch.Toxicol. 1992;66:(5):321-326.

92. Reddy, J. K., Reddy, M. K., Usman, M. I., Lalwani, N. D., and Rao, M. S. Comparison of hepatic peroxisome proliferative effect and its implication for hepatocarcinogenicity of phthalate esters, di(2-ethylhexyl) phthalate, and di(2-ethylhexyl) adipate with a hypolipidemic drug. Environ.Health Perspect. 1986;65:317-327.

93. Barber, E. D., Astill, B. D., Moran, E. J., Schneider, B. F., Gray, T. J., Lake, B. G., and Evans, J. G. Peroxisome induction studies on seven phthalate esters. Toxicol.Ind.Health. 1987;3:7-22.

94. Lake BG. Mechanisms of hepatocarcinogenicity of peroxisome-proliferating drugs and chemicals. Annu Rev


106

Pharmacol Toxicol. 1995;35:483-507.

95. Lake, B. G., Price, R. J., Cunninghame, M. E., and Walters, D. G. Comparison of the effects of di-(2-ethylhexyl)adipate on hepatic peroxisome proliferation and cell replication in the rat and mouse. Toxicology. 1997;123:(3):217-226.

96. Tomaszewski, K. E., Agarwal, D. K., and Melnick, R. L. Invitro steady-state levels of hydrogen eroxide after exposure of male F344 rats and female B6C3F1 mice to hepatic peroxisome proliferators. Carcinogenesis. 1986;7:(11):1871-1876.

97. von Däniken A., Lutz, W. K., Jâckh, R., and Schlatter, C. Investigation of the potential for binding of di(2-ethylhexyl) phthalate and di(2-ethylhexyl) adipate to liver DNA in vivo. Toxicol Appl Pharmacol. 1984;73:(3):373-387.

98. Büsser, M.-T. and Lutz, W. K. Stimulation of DNA Synthesis in Rat and Mouse Liver by Various Tumor Promoters. Carcinogenesis. 1987;8:(10):1433-1437.

99. Takagi, A., Sai, K., Umemura, T., Hasegawa, R., and Kurokawa, Y. Significant increase of 8-hydroxydeoxyguanosine in liver DNA of rats following short-term exposure to the peroxisome proliferators di(2-ethylhexyl)phthalate and di(2-ethylhexyl)adipate. Jpn.J.Cancer Res. 1990;81:213-215.

100. Kawashima, Y., Hanioka, N., Matsumura, M., and Kozuka, H. Induction of microsomal stearoyl-CoA desaturation by the administration of various peroxisome proliferators. (Secondary reference in IARC 2000). Biochim.Biophys.Acta. 1983;752:259-264.

101. Kawashima Y, Nakagawa S, Tachibana Y, and Kozuka H. Effects of peroxisome proliferators on fatty acid-binding protein in rat liver. (Secondary reference in IARC 2000). Biochim Biophys Acta. 1983;754:21-27.

102. Yanagita T., Satoh M., Nomura H., Enomoto N., and Sugano M. Alteration of hepatic phospholipids in rats and mice by feeding di-(2-ethylhexyl)adipate and di-(2-ethylhexyl)phthalate. (Secondary reference in IARC 2000.). Lipids. 1987;22:572-577.

103. Motojima, K., Passilly, P., Peters, J. M., Gonzalez, F. J., and Latruffe, N. Expression of putative fatty acid transporter genes are regulated by peroxisome proliferator-activated receptor alpha and gamma activators in a tissue- and inducer-specific manner. (Secondary reference in IARC 2000). J.Biol.Chem. 1998;273:16710-16714.

104. Organisation for Economic Co-Operation and Development.SIDS Initial Report for Siam 4 - Dibutyl Adipate CAS No. 105-99-7. 1996. http://www.chem.unep.ch/irptc/sids/OECDSIDS/105997.pdf. Accessed 7-29-2010.

105. AMA Laboratories. Acute oral toxicity of Liquiwax DIADD (Dioctyldodecyl Dodecanedioate). AMA Ref No. WPAT90-59/OT5982.II. Unpublished data submitted by the Council (3 pp). 12-13-1990.

106. AMA Laboratories. Acute oral toxicity of Liquiwax DICDD (Diisocetyl Dodecanedioate). AMA Ref No: WPAT90-59/OT6098.II Unpublished data submitted by the Council (3 pp). 1-3-1991.

107. AMA Laboratories. Acute dermal toxicity - limit test - Liquiiwax DIADD (Dioctyldedecyl Dodecanediaote). AMA Ref No. WPAT93-155/AD1076.BII. Unpublished data submitted by Council (4 pp). 6-14-1993.

108. EviC-CEBA. Attestation of biological significance (acute oral toxicity and dermal irritation) on diethylhexyl sebacate. Study ref. T 207/4072. Unpublished data submitted by the Council (2 pp). 4-7-1994.

109. EviC-CEBA. Attestation of biological significance (acute oral toxicity and dermal irritation) on diisocetyl adipate. Study ref. T 207/4073. Unpublished data submitted by the Council (2 pp). 4-7-1994.

110. EviC-CEBA. Attestation of biological test (acute oral toxicity and dermal irritation) on diisodecyl adipate. Study ref. T 207/4076. Unpublished data submitted by the Council (2 pp). 5-9-1994.


107

111. EviC-CEBA. Attestation of biological significance (acute oral toxicity and dermal irritation) on dioctyldodecyl adipate. Study ref. T 207/4071. Unpublished data submitted by the Council (2 pp). 5-9-1994.

112. EviC-CEBA. Study of acute toxicity and local tolerance (acute oral, acute dermal, and ocular irritation) on diisopropyl adipate. Study report: Te 297/98-1589 and Te 298/98-1589. Unpublished data submitted by the Council (4 pp). 5-27-1998.

113. Singh AR, Lawrence WH, and Autian J. Embryonic-fetal toxicity and teratogenic effects of adipic acid esters in rats. J Pharm Sci. 1973;62:(10):1596-1600.

114. Smith CC. Toxicity of butyl stearate, dibutyl sebacate, dibutyl phthalate, and methoxyethyl oleate. AMA Arch.Ind.Hyg.Occup.Med. 1953;7:310-318.

115. Organisation for Economic Co-Operation and Development.SIDS Initial Report for SIAM 10 - Bis(2-ethylhexyl) Adipate (DEHA), CAS No. 103-23-1. 2000. http://www.chem.unep.ch/irptc/sids/OECDSIDS/103231.pdf. Accessed 7-29-2010.

116. Lee, K. P., Valentine, R., and Bogdanffy, M. S. Nasal lesion development and reversibility in rats exposed to aerosols of dibasic esters. Toxicol.Pathol. 1992;20:(3 Part 1):376-393.

117. ExxonMobil Chemical Company.High Production Volume (HPV) Chemical Challenge Program. Test plan for the alkyl alcohols C6-C13 Category. 2-5-2002. http://www.epa.gov/HPV/pubs/summaries/alkal613/c13590rs.pdf. Accessed 2010.

118. Smyth HF, Carpenter CP, and Weil CS. Range-finding toxicity data: List IV. AMA Arch.Ind.Hyg.Occup.Med. 1949;4:119-122.

119. Wato, E., Asahiyama, M., Suzuki, A., Funyu, S., and Amano, Y. Collaborative work on evaluation of ovarian toxicity. 9) Effects of 2- or 4-week repeated dose studies and fertility study of di(2-ethylhexyl)adipate (DEHA) in female rats. J.Toxicol.Sci. 2009;34:(Special Issue I):SP101-SP109.

120. Consumer Product Testing. 1991. Primary dermal irritation in rabbits, primary ocular irritation in rabbits of Schermcemol DIS (Diisopropyl Sebacate). Experiment Reference Number: 91055. (Material tested as supplied - approx. 100%). 3 pages.

121. MB Research Laboratories. 2003. EpiOcular MTT viability assay of a cream containing 1.2% Diethylhexyl Sebacate. 10 pages.

122. AMA Laboratories. Primary eye irritation of liquiwax DIADD (Dioctyldodecyl Dodecanedioate). AMA Lab No. WPAT90-59/PE5982.II. Unpublished data submitted by theCouncil (5 pp). 12-3-1990.

123. AMA Laboratories. Primary eye irritation of liquiwax DICDD (Diisocetyl Dodecanedioate). AMA Ref No: WPAT90-59/PE6098.II. Unpublished data submitted by the Council (3 pp). 12-22-1990.

124. Personal Care Products Council. 1989. Summary of safety data on Diethyl Sebacate (primary skin irritation, cumulative skin irritation, contact allergenicity). 8 pages.

125. EviC-CEBA. Attestation of biological significance (acute oral toxicity and dermal irritation) on diisopropyl sebacate. Study ref. T 207/4078. Unpublished data submitted by the Council (2 pp). 4-7-1998.

126. AMA Laboratories. Guinea pig maximization test (Kligman) on liquiwax DIADD (Dioctyldodecyl Dodecanedioate). AMA Ref No: WPAT93-GPMB1076.BII. Unpublished data submitted by the Council (6 pp). 6-14-1993.

127. Environmental Protection Agency.Integrated Risk Information System. Di(2-ethylhexyl)adipate. (CASRN 103-23-1). 3-6-2010. N:\CIR\DicarboxylicAcids\DatabaseSearchResults\EPA\IRIS-searched7-8-10_updatred3-16-10.mht. Accessed 7-8-2010.


108

128. Dalgaard, M., Hass, U., Vinggaard, A. M., Jarfelt, K., Lam, H. R., rensen, I. K., Sommer, H. M., and Ladefoged, O. Di(2-ethylhexyl) adipate (DEHA) induced developmental toxicity but not antiandrogenic effects in pre- and postnatally exposed Wistar rats. Reprod.Toxicol. 2003;17:(2):163-170.

129. Kang, J. S., Morimura, K., Toda, C., Wanibuchi, H., Wei, M., Kojima, N., and Fukushima, S. Testicular toxicity of DEHP, but not DEHA, is elevated under conditions of thioacetamide-induced liver damage. Reprod.Toxicol. 2006;21:253-259.

130. Alvarez, L., Driscoll, C., Kelly, D. P., Staples, R. E., Chromey, N. C., and Kennedy, G. L., Jr. Developmental toxicity of dibasic esters by inhalation in the rat. Drug Chem.Toxicol. 1995;189:(4):295-314.

131. Kelly, D. P., Kennedy, G. L., Jr., and KEENAN, C. M. Reproduction study with dibasic esters following inhalation in the rat. Drug Chem.Toxicol. 1998;21:(3):253-267.

132. Miyata, K., Shiraishi, K., Houshuyama, S., Imatanaka, N., Umano, T., Minobe, Y., and Yamasaki, K. Subacute oral toxicity study of di(2-ethylhexyl)adipate based on the draft protocol for the "Enhanced OECD Test Guideline no. 407". Arch.Toxicol. 2006;80:181-186.

133. Ghisari, M. and Bonefeld-Jorgensen, E. C. Effects of plasticizers and their mixtures on estrogen receptor and thyroid hormone functions. Toxicol.Lett. 2009;189:(1):67-77.

134. Andersen, P. H. and Jensen, N. J. Mutagenic investigation of flavourings: dimethyl succinate, ethyl pyruvate and aconitic acid are negative in the Salmonella/mammalian-microsome test. Food Addit.Contam. 1984;1:(3):283-288.

135. National Toxicology Program.Salmonella assay on dimethyl succinate. Study ID: 947738. 1988. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=947738&cas%5Fno=106%2D65%2D0&activetab=detail. Accessed 7-26-2010.

136. National Toxicology Program.Salmonella assay on dimethyl glutarate. Study ID A20348. 1995. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=A20348&cas%5Fno=1119%2D40%2D0&activetab=detail. Accessed 7-26-2010.

137. National Toxicology Program.Salmonella assay on dimethyl adipate. Study ID: A45330. 1994. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=A45330&cas%5Fno=627%2D93%2D0&activetab=detail. Accessed 7-26-2010.

138. Zeiger E, Haworth E, Mortelmans S, and et al. Mutagenicity testing of di(2-ethylhexyl) phthalate and related chemicals in Salmonella. Environ Mutagen. 1985;7:213-232.

139. Warren JR, Lalwani, N. D., and Reddy, J. K. Phthalate esters as peroxisome proliferator carcinogens. Environ.Health Perspect. 1982;45:35-40.

140. Simmon VF, Kauhanen K, and Tardiff R.G. Mutagenic activity of chemicals identified in drinking water. Dev Toxicol Environ Sci. 1977;2:249-258.

141. National Toxicology Program.Salmonella assay eith diethylhexyl adipate. Study ID: 963935. 1988. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=963935&cas%5Fno=103%2D23%2D1&activetab=detail. Accessed 7-26-2010.

142. Seed JL. Mutagenic activity of phthalate estes in bacterial seed liquid suspension assays. Environ.Health Perspect. 1982;45:111-114.

143. McGregor, D. B., Brown, A., Cattanach, P., Edwards, I., McBride, D., Riach, C., and Caspary, W. J. Responses of the L5178Y tk+/tk- mouse lymphoma cell forward mutation assay: III. 72 coded chemicals. (Secondary reference in IARC 2000). Environ.Mol.Mutagen. 1988;12:(1):85-154.


109

144. Reisenbichler, H. and Eckl, P. M. Genotoxic effects of selected peroxisome proliferators. (Secondary reference in IARC 2000). Mutat.Res. 1993;286:135-144.

145. Galloway SM, Armstrong MJ, Rueben C, Colman S, Brown B, CAnnon C, Bloom AD, Nakamura F, Ahmed M, Duk S, Rimpo J, Margolin BH, REsnick MA, Anderson B, and Zeiger E. Chromosome aberrations and sister chromatid exchanges in Chinese hamster ovary cells: Evaluation of 108 chemicals. Environ Mol Mutagen. 1987;10:(Suppl 10):1-175.

146. Shelby, MD, Erexson GL, Hook GH, and Tice RR. Evaluation of a three-exposure mouse bone marrow micronucleus protocol: Results with 49 chemicals. Environ Mol Mutagen. 1993;21:160-179.

147. Shelby, MD and Witt, KL. Comparison of results from mouse bone marrow chromosome aberration and micronucleus tests. Environ Mol Mutagen. 1995;25:302-313.

148. National Toxicology Program.Chromosome aberration assay of diethylhexyl adipate. Study ID: 959525. 1988. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=invivoca.casummary&study_no=959525&cas_no=103%2D23%2D1&endpointlist=CA. Accessed 7-26-2010.

149. DiVincenzo, G. D., Hamilton, M. L., Mueller, K. R., Donish, W. H., and Barber, E. D. Bacterial mutagenicity testing of urine from rats dosed with 2-ethylhexanol derived plasticizers. Toxicology. 1985;34:(3):247-259.

150. McKee, R. H., Lington, A. W., and Traul, K. A. An evaluation of the genotoxic potential of di-isononyl adipate. Environ.Mutagen. 1986;8:(6):817-827.

151. Szybalski W. Special microbiological systems - Observations on chemical mutagenesis in microorganisms. Ann.NY Acad.Sci. 1958;76:475-489.

152. Wild, D., King, M. T., Gocke, E., and Eckhardt, K. Study of artificial flavoring substances for mutagenicity in the salmonella/microsome, basc and micronucleus tests. Fd Chem Toxicol. 1983;21:707-719.

153. TOXNET.CCRIS database - Dibutyl Sebacate. CAS No. 109-43-3. 2-12-2001. http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~LfAk2H:2. Accessed 7-26-2010.

154. TOXNET.CCRIS database - Diethylhexyl Sebacate. CAS NO. 122-62-3. 6-2-2010. http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~J98xpD:1. Accessed 7-26-2010.

155. Osterle D and Deml E. Promoting activity of di(2-ethylhexyl)phthalate in rat liver foci bioassay. J.Cancer Res.Clin.Oncol. 1988;114:(2):133-136.

156. Kluwe, W. M. Carcinogenic potential of phthalic acid esters and related compounds: structure-activity relationships. Environ.Health Perspect. 1986;65:271-278.

157. Hasegawa R and Ito N. Liver medium-term bioassay in rats for screening of carcinogenesis and modifying factors in hepatocarcinogenesis. Fd Chem Toxicol. 1992;30:(11):979-992.

158. AMA Laboratories. 50 Human subject repeat insult patch test skin irritation/sensitization evaluation on Liquiwax DISA (Diisostearyl Adipate), DICDD (Diisocetyl Dodecanedioate), and DIADD (Dioctyldodecyl Dodecanedioate). AMA Ref No: WP96-BERN1-18/RIPT4618.BII. Unpublished data submitted by the Council. 4-11-1996.

159. Anonymous. Clinical evaluation report: human patch test of a body cream containing 1.5% diethyl sebacate. Unpublished data submittd by the Personal Care Products Council. 2003.

160. KGL Inc. 2003. An evaluation of the contact-sensitization potential of a topical coded product (body cream containing 1.5% diethyl sebacate) in human skin by means of the maximization assay. 10 pages.


110

161. Anonymous. Clinical evaluation report: human patch test of a foundation containing 1.8% diisopropyl sebacate. Unpublished data submitted by the Council.. 2000.

162. Product Investigations Inc. 2005. Determination of the irritating and sensitizing propensities of Schercemol DIS (Diisopropyl Sebacate) on human skin. Report: PII No. 19745. (Material tested as supplied - approx. 100%). 12 pages.

163. KGL Inc. 2006. An evaluation of the contact-sensitization potential of a topical coded product (foundation containing 2.2% diisopropyl sebacate) in human skin by means of the maximization assay. 10 pages.

164. Reliance Clinical Testing Services. 2007. Summary of HRIPT of two heat protection hair sprays containing 1% Diisopropyl Sebacate. 1 pages.

165. Essex Testing Clinic Inc. 2007. Summary of HRIPT of a heat protection hair spray containing 7.2% Diisopropyl Sebacate.

166. Kimura M and Kawada A. Contact dermatitis due to Diethyl Sebacate. Contact Dermatitis. 1999;40:48-49.

167. Narita T, Oiso N, Ota T, Kawara S, and Kawada A. Allergic contact dermatitis due to Diethyl Sebacate in a hand cream. Contact Dermatitis. 2006;55:117.

168. Sasaki E, Hata M, Aramaki J, and Honda M. Allergic contact dermatitis due to Diethyl Sebacate. Contact Dermatitis. 1997;36:172.

169. Soga F, Katoh N, and Kishimoto S. Contact dermatitis due to lanoconazole, cetyl alcohol and Diethyl Sebacate in lanoconazole cream. Contact Dermatitis. 2004;50:49-50.

170. Tanaka M, Kobayashi S, Murata T, Tanikawa A, and Nishikawa T. Allergic contact dermatitis from Diethyl Sebacate in lanoconazole cream. Contact Dermatitis. 2000;43:233-234.

171. De Groot AC, Conemans JM, and Schutte T. Contact allergy to Diisopropyl Sebacate in Zineryt lotion. Contact Dermatitis. 1991;25:260-261.

172. Dooms-Goossens A, De Veyhlder H, De Boulle K, and Maertens M. Allergic contact dermatitis due to Diisopropyl Sebacate. Contact Dermatitis. 1986;15:192.

173. Elder RL (ed). Final Report on the Safety Assessment of Stearyl Alcohol, Oleyl Alcohol, and Octyl Dodecanol. Journal of the American College of Toxicology. 1985;4:(5):1-29.

174. Andersen FA,ed. Final report on the safety assessment of Dibutyl Adipate. J Am Coll Toxicol. 1996;15:(4):295-300.

175. Organisation for Economic Co-Operation and Development.SIDS Initial Assessment for SIAM 16 - Disodium Succinate, CAS No. 150-90-3. 2003. http://www.chem.unep.ch/irptc/sids/OECDSIDS/150903.pdf. Accessed 7-29-2010.

176. TOXNET.CCRIS database - Diodium Succinate. 2-14-1997. Accessed 7-26-2010.

177. National Toxicology Program.Salmonella assay on glutaric acid. Study ID: 994718. 1989. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=salmonella.salmonellaData&endpointlist=SA&study%5Fno=994718&cas%5Fno=110%2D94%2D1&activetab=detail. Accessed 7-26-2010.

178. TOXNET.CCRIS database - Dodecanedioic Acid. CAS No 111-20-6. 10-22-1990. http://toxnet.nlm.nih.gov/cgi-bin/sis/search. Accessed 7-26-2010.

179. Heldreth BA. Final report on Methyl Acetate, Simple Alkyl Acetate Estes and Related Alcohols (Draft). Report in progress. Available from the Cosmetic Ingredient Review. 2010.


111

180. AMA Laboratories. Primary skin irritation of liquiwax DIADD (Dioctyldodecyl Dodecanediaote.) AMA Ref No. WPAT90-59/PS5982.II. Unpublished data submitted by the Council (4 pp). 12-3-1990.

181. AMA Laboratories. Primary skin irritation of liquiwax DICDD (Diisocetyl Dodecanedioate). Ref: WPAT90-59/PS6098.II. Unpublished data submitted by the Council (3 pp). 12-22-1990.

182. Opdyke, D. L. J. Fragrance Raw Materials Monographs - Supplement to Earlier Monographs on Fragrance Materials. 1973. 1079

183. TOXNET.CCRIS database - Diisobutyl Adipate. CAS No. 141-04-8. 2-12-2001. http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~p2E3uo:6. Accessed 7-26-2010.

184. National Toxicology Program.Micronucleus test on dimethyl succinate. Study ID: A71006. 1996. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=micronucleus.micronucleusData&endpointlist=MN&current%5Fstrain%5Fid=F344&cas%5Fno=106%2D65%2D0&study%5Fno=A71006&activetab=detail. Accessed 7-26-2010.

185. National Toxicology Program.Micronucleus test on dimetyl glutarate. Study ID A36863. 1995. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=micronucleus.micronucleusData&cas_no=1119%2D40%2D0&endpointlist=MN. Accessed 7-26-2010.

186. National Toxicology Program.Micronucleus test on dimethyl adipate. Study ID: A86146. 1994. http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=micronucleus.micronucleusData&current%5Fstrain%5Fid=F344&endpointlist=MN&cas%5Fno=627%2D93%2D0&study%5Fno=A86146&activetab=detail. Accessed 7-26-2010.

187. Andersen FA (ed). Final report on the safety assessment of Methyl Alcohol. Injt J Toxicol. 2001;20:(Suppl 1):57-85.

188. Stillman MA, Maiback HI, and Shalita AR. Relative irritancy of free fatty acids of different chain length. Contact Derm. 1975;1:65-69.

189. Wahlberg JE and MAibach HI. Nonanoic acid irrigation: A positive control at routine patch testing? Contact Derm. 1980;6:(2):128-130.

190. Agner T and Serup J. Nonanoic acid irrigation: A positive contorl at routine patch testing? Contact Derm. 1987;17:(4):20-211.

191. Willis CM, Stephens JM, and Wilkinson JD. Experimentally-induced irritant contact dermatitis. Determination of optimum irritant concentrations. Contact Derm. 2010;1:20-24.

192. Agner T and Serup J. Contact thermography for assessment of skin damage due to experimental irritants. Acta Derm Venereol. 1988;68:(2):192-195.

193. Agner T and Serup J. Seasonal variation ofskin resistance to irritants. Br J Dermatol. 2010;121:(3):323-328.

194. Damato JM, Martin DM, and Fehn PA. Allergic contact sensitization test of a spray concentrate containining 80.74% isopropyl alcohol. 1979.

195. Anonymous. Final Report Repeated Insult Patch Test of a Hair Dye Base (3373) Containing 2.85% Isopropyl Alcohol and 1.95% Isopropyl Acetate. Unpublished data submitted by teh Council. 2010.

196. Suihko C and Serup J. Fluorescence confocal laser scanning microscopy for in vivo imaging of epidermal reactions to two experimental irritants. Skin Res Technol. 2008;14:(4):498-503.

197. Elder RL (ed). Final Report on the Safety Assessment of Cetearyl Alcohol, Cetyl Alcohol, lsostearyl Alcohol, Myristyl Alcohol, and Behenyl Alcohol. Journal of the American College of Toxicology. 1988;7:(3):359-413.


112

198. Andersen, F. A. Final Report on the Safety Assessment of Formic Acid. International Journal of Toxicology. 1997;16:(3).

199. International Programme on Chemical Safety.Methanol: Poisons Information Monograph 335. 2009. http://www.inchem.org/documents/pims/chemical/pim335.htm. Accessed 10-20-2009.

200. D'Alessandro, A., Osterloh, J. D., Chuwers, P., Quinlan, P. J., Kelly, T. J., and Becker, C. E. Formate in serum and urine after controlled methanol exposure at the threshold limit value. Environ.Health Perspect. 1994;102:(2):178-181.

201. Andersen, F. A. Final Report on the Safety Assessment of Methyl Alcohol. International Journal of Toxicology. 2001;20:((Suppl. 1)):57-85.

202. American Chemistry Council and Oxo Process Panel. Screening Information Data Set (SIDS) Initial Assessment Report for SIDS Initial Assessment Meeting (SIAM) 27: n-Propyl Acetate. OECD. 2008.

203. Nelson BK, Brightwell WS, Taylor BJ, Khan A, Burg JR, Kreig EF Jr, and Massari VJ. Behavioral teratology investigatoi of 1-propanol administered by inhalation to rats. Neurotoxicol Teratol. 1989;11:(2):153-159.

204. Agner, T. and Serup J. Skin reactions to irritants assessed by polysulfide rubber replica. Contact Dermatitis. 1987. 17:(4):205-211.

205. Martinez, T. T., Jaeger, R. W., deCastro, F. J., Thompson, M. W., and Hamilton, M. F. A comparison of the absorption and metabolism of isopropyl alcohol by oral, dermal and inhalation routes. Vet Hum Toxicol. 1986;28:(3):233-236.

206. Burleight-Flayer H, Garman R, Neptun D, Bevan C, Gardiner T, Kapp R, Tyler T, and Wright G. Isopropanol vapor inhalaiton oncogenicity study in Fischer 344 rats and CD-1 mice. Fund Appl Toxicol. 1997;36:(2):95-111.

207. International Programme on Chemical Safety.Isopropyl Alcohol: Poisons Information Monograph 290. 2009. http://www.inchem.org/documents/pims/chemical/pim290.htm. Accessed 10-12-2009.

208. Tyl, R. W., Masten, L. W., Marr, M. C., Myers, C. B., Slauter, R. W., Gardiner, T. H., Strother, D. E., McKee, R. H., and Tyler, T. R. Developmental toxicity evaluation of isopropanol by gavage in rats and rabbits. Fundam.Appl Toxicol. 1994;22:(1):139-151.

209. High Production Volume (HPV) Chemical Challenge Program. Test Plan for the Alkyl Alcohols C6 - C13 Category. 2002.

210. International Program on Chemical Safety.Butyl acetates. 2005. http://www.inchem.org/documents/cicads/cicad64.htm. Accessed 11-20-2009.

211. Belsito, D., Bickers, D., Bruze, M., Calow, P., Greim, H., Hanifin, J. M., Rogers, A. E., Saurat, J. H., Sipes, I. G., and Tagami, H. A Safety Assesment of Branched Chain Saturated Alcohols When Used as Fragrance Ingredients. Food Chem Toxicol. 2010;48:(Supplement 4):S1-S46.

212. Kawaguchi, M., Yamazaki, T., and Nakazawa, H. Biological effects of di(2-ethylhexyl)adipate. Environmental.Sciences.: an.International.Journal of Environmental.Physiology.and Toxicology. 2002;9:(2-3):198.


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APPENDIX I – ESTEASE METABOLITE SUMMARY DATA

Decyl Alcohol – metabolite of Decyl Succinate Clinical Irritation and Sensitization Tested in at a concentration of 3% in petrolatum, decyl alcohol produced no irritation in a 48 h closed-patch test in 25 human subjects.182 Methanol – metabolite of Dimethyl Succinate, Dimethyl Glutarate, Dimethyl Adipate Absorption, Distribution, Metabolism, and Excretion

Methanol is further metabolized to formaldehyde and then to formic acid. The CIR Expert Panel concluded that formic acid is safe where used in cosmetic formulations as a pH adjustor with a 64 ppm limit for the free acid.198 The main toxicological risks in humans are severe metabolic acidosis with increased anion gap, typically following oral exposure resulting in > 100 mg/L of formate in the urine.199 The acidosis and the formic acid metabolite are believed to play a central role in both the central nervous system toxicity and the ocular toxicity. A study to determine the formate levels that resulted from exposure of human volunteers to 200 ppm of methanol for 4 h was conducted. Human volunteers (n=27; age 20-55 y) were exposed to 200 ppm methanol (the Occupational Safety and Health Administration [OSHA] Permissible Exposure Limit) for 4 h and to water vapor for 4 h in a double-blind, random study.200 Urine samples were collected at 0, 4 and 8 h and blood samples were collected from the subjects before they entered the chamber, every 15 min for the first hour, every 30 min from the first to the third hour and at 4 h. Urine and serum samples were analyzed for formate (LOD 0.5 mg/L). Twenty-six of 27 enrolled subjects completed the study (11 females and 15 males). The researchers did not find any statistically significant differences in serum or urine formate levels between the two exposure conditions at any time point. At the end of the 4 h methanol exposure, formate concentrations of 14.28 ± 8.90 and 7.14 ± 5.17 mg/L were measured in serum and urine, respectively. Under control conditions, formate concentrations of 12.68 ± 6.43 (p=0.38; n=26) and 6.64 ± 4.26 (p=0.59; n=25) mg/L were measured in serum and urine respectively. After 8 h (4 h of no exposure) the serum concentrations were not statistically different with 12.38 ± 6.53 mg/L under methanol exposure conditions and 12.95 ± 8.01 (P=0.6; n=26) under control conditions. Urine formate concentrations after 8 h were 6.08 ± 3.49 and 5.64 ±3.70 mg/L (p=0.6; n=25) in exposed and control conditions, respectively, and were not statistically significantly different. From CIR Final Report on Methyl Acetate179

Clinical Irritation and Sensitization

Methyl Alcohol caused primary irritation to the skin; prolonged and repeated contact with Methyl Alcohol resulted in de-fatting and dermatitis. In one occupational study, 3.2% of 274 metalworkers with dermatitis had positive results to a patch test of 30% Methyl Alcohol. Typical allergic responses observed after contact with alcohols were eczematous eruption and wheal and flare at the exposure sites. Eczema and erythema were reported after the consumption of alcoholic beverages by persons sensitized to ethyl alcohol. Five percent Methyl Alcohol caused a slight positive (+) reaction in a closed patch test for allergic contact dermatitis, and concentrations of 7% and 70% caused (+++) reactions. From the CIR final report on methyl alcohol201

Clinical Assessment of Safety

Clinical data show that Methyl Alcohol can cause severe metabolic acidosis, blindness, and death: toxicity was manifested earlier and at a lower dose compared to ethyl alcohol, but the comparative fatal dose was the same for both alcohols. All routes of exposure were toxicologically equivalent, as the alcohol distributed readily and uniformly throughout all tissues and organs. Individual susceptibilities to Methyl Alcohol varied, but typically, the ingestion of 80 to 150 ml of 80% Methyl Alcohol was fatal. Symptoms of Methyl Alcohol intoxication after ingestion were delayed for 12 to 18 hours; afterwards, the symptoms included headache, anorexia, weakness, fatigue, leg cramps, and/or pain and vertigo. Severe gastrointestinal pain, nausea, vomiting, diarrhea, mania, failed vision, and convulsions could occur. Chronic exposure to Methyl Alcohol could cause edema, granular degeneration, and necrosis of heart muscle fibers, as well as fatty degeneration of the heart muscle; sudden cardiac failure was associated with Methyl Alcohol intoxication. The liver and kidneys often had parenchymatous degeneration, and the liver had focal necrosis and fatty infiltration. Severe acidosis was necessary for the development of blindness. Similar symptoms were observed after percutaneous or inhalation exposure to Methyl Alcohol.


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From the CIR final report on methyl alcohol201 Propyl Alcohol – metabolite of Dipropyl Adipate Absorption, Distribution, Metabolism, and Excretion

Rats (strain/sex/number not specified) were exposed via inhalation to 2,000 ppm (8360 mg/m3) for 90 min.202 Propyl acetate was rapidly hydrolyzed to propyl alcohol. During the 90 min exposure period, blood levels of propyl alcohol were between 2.6 and 7.7 fold greater than propyl acetate. From the CIR final report on Methyl Acetate179

Reproductive and Developmental Toxicity

The effects of propyl alcohol on fertility were investigated by exposing male Sprague-Dawley rats (18/group) to 0, 3500 or 7000 ppm (0, 8.61 or 17.2 mg/L) propyl alcohol vapor via inhalation 7 h/day, 7days/week for 62 days, prior to mating with unexposed virgin females.203 Female Sprague-Dawley rats (15/group) were similarly exposed and mated with unexposed males. Following parturition, litters were culled to 4/sex and the pups fostered by unexposed dams. The pups were weaned on post natal day (PND) 25 and weighed on PND 7, 14, 21, 28 and 35. Male rats exposed to 7000 ppm exhibited a decrease in mating success with 2/16 producing a litter (1 male died as a result of a cage fight and 1 male did not mate). Mating success was not affected in 3500 ppm exposed males or in females. Six males from the 7000 ppm group were retained to determine if this effect was reversible. All 6 males successfully mated 15 weeks after exposure. The authors reported that weight gain was not affected in 7000 ppm exposed females (data not shown), but feed intake was decreased in this treatment group. Crooked tails were observed in 2-3 offspring in 2 of 15 litters from the 7000 ppm maternally exposed group. No other effects on female fertility were reported. No significant differences resulted between offspring of the 7000 ppm group and controls on several behavioral toxicology measures including the Ascent test, Rotorod test, Open Field test, activity test, running wheel activity, avoidance conditioning, and operant conditioning. Activity measures were significantly different between offspring of the 3500 ppm exposure group and controls. From the CIR final report on Methyl Acetate179


A cumulative irritation study was conducted involving 20 male subjects, where the relative irritancy of free fatty acids of different chain lengths was evaluated.188 Equimolar concentrations (0.5 M and 1.0 M) of even- and odd-numbered - straight chain saturated fatty acids were dissolved in propanol. Each Al-test® patch containing a fatty acid (0.5 M) was applied to the interscapular area of 10 subjects, and, similarly, each fatty acid was applied at a higher concentration (1.0 M) to the remaining 10 subjects. A control patch containing propanol was also applied to each subject. Patches remained in place for 24 h and reactions were scored 30 minutes after patch removal. This procedure was repeated daily for a total of 10 applications. In both groups of 10 subjects, there were no reactions to propanol. In an irritation study, wherein 116 healthy male subjects (21 to 55 years old) were patch tested with pelargonic acid at concentrations of 5%, 10%, 20%, and 39.9% in propanol, a propanol-treated control patch was used.189 Dose response curves were developed. Patches (Al-test® discs) were saturated with 0.04 ml of a test solution and applied to the upper back for 48 h. Reactions were scored at 48 h and 96 h post-application. There were no reactions to propanol. In an another irritation study, wherein 16 volunteers (10 females, 6 males; median age of 29.5 years) were patch tested (closed patches, Finn chambers) with 20% pelargonic acid in propanol (pH of 4.3), propanol was one of the controls used.204 Patches were applied to the anterolateral surface of both upper arms for 24 h. Reactions were scored at 24, 48, and 96 h post-application according to the following scale: 0 (no reaction) to 3 (strong positive reaction: marked erythema, infiltration, possibly vesicles, bullae, pustules and/or pronounced crusting). There were no reactions to propanol. A skin irritation study was conducted using 42 healthy, non-atopic male volunteers (mean age = 34 years; skin types: II [20 subjects], III [17 subjects], and IV [5 subjects]).190 Pelargonic acid was patch-tested (Finn chambers, volar forearm) at the following concentrations (in propanol): 40% (12 subjects), 60% (32 subjects), 70% (32 subjects), and 80% (28 subjects), and propanol was used as a control. Each subject received between 3 and 10 patch tests. The patches remained in place for 48 h, and reactions were scored 1 h later according to the following scale: - (no visible reaction) to 4+ (intense erythema with bullous formation). There were no reactions to propanol.


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In an irritation study, wherein 16 healthy subjects (ages not stated) were patch tested with pelargonic acid (20% in propanol), propanol was used as a control.191 Closed patches (Finn chambers) containing the test substance were applied to the anterolateral surface of both upper arms. The patches were removed at 24 h post-application and reactions were scored at 24 h and 96 h post-application. There were no reactions to propanol. In study conducted to investigate a possible seasonal variation in the skin response to pelargonic acid during the winter and summer, propanol was used as a control.193 The study was conducted using 17 healthy volunteers (10 males, 7 females; mean age = 27 years). The test substance was applied (closed patch, Finn chamber) to each arm for 24 h. Reactions were scored at 30 min post-removal. Reactions were not observed at sites treated with propanol, water, or to which an empty chamber was applied. From CIR final report on Methyl Acetate179

Cetyl Alcohol – metabolite of Dicetyl Succinate and Dicetyl Adipate Clinical Irritation and Sensitization

A topical tolerance study involving an 11.5% Cetyl Alcohol cream base was conducted with 80 male subjects, ranging in age from 21 to 52 years and in weight from 120 to 220 pounds. The preparations were applied five times daily (every 3 hours) for 10 days. One subject had erythema, folliculitis, and pustule formation (forearm site). A formulation containing 6.0% Cetyl Alcohol was tested for its skin irritation potential in 20 subjects according to the protocol stated above. The product did not induce skin irritation. In another study, the skin irritation potential of a cream containing 6.0% Cetyl Alcohol was evaluated in 12 female subjects (18-60 years old). The total irritation score (all panelists) for the 21 applications was 418, indicating mild cumulative irritation. The skin irritation and sensitization potential of a product containing 8.4% Cetyl Alcohol was evaluated in 110 female subjects. Fourteen days after scoring of the tenth application site, a challenge patch was applied to each subject and removed after 48 h; sites were scored after patch removal. The product did not induce primary irritation or sensitization. The sensitization potential of a cream containing 3.0% Cetearyl Alcohol was evaluated in 25 subjects (18-25 years old). Following a 10-day non-treatment period, occlusive challenge patches were applied to new sites and removed after 48 h. Sensitization reactions were not observed in any of the subjects. From the CIR final report on cetyl alcohol197

Photosensitization

The photosensitization potential of a lipstick product containing 4.0% Cetyl Alcohol was evaluated in 52 subjects. The experimental procedure was not stated. Photosensitization reactions were not noted in any of the subjects. In another study, a skin care preparation containing 1.0% Cetyl Alcohol did not induce photosensitization in the 407 subjects tested. The experimental procedure was not stated. From CIR final report on cetyl alcohol197

Isopropyl Alcohol – metabolite of Diisopropyl Adipate and Diisopropyl Sebacate Absorption, Distribution, Metabolism, and Excretion

Male rabbits (3/group; strain not specified) were treated by different routes of exposure to compare the absorption and metabolism of isopropyl alcohol.205 Groups 1 and 2 were treated via gavage with the equivalent of 2 and 4 ml/kg absolute isopropyl alcohol, respectively, as a 35% isopropanol/water solution. Groups 3 and 4 were treated via whole-body inhalation for 4 h (towels soaked with isopropyl alcohol were place in the inhalation chamber and replenished at ½ hour intervals to maintained a saturated environment; no exact concentration given), with Group 3 animals receiving an additional dermal exposure in the form of a towel soaked with 70% isopropyl alcohol applied to the animals’ chests and Group 4 animals having plastic barriers on their chests and towels prepared the same way as in Group 3 applied on top of the plastic barriers. The alcohol on the towels was replenished at half hour intervals throughout the duration of the experiment. Blood samples were taken at 0, 1, 2, 3 and 4 h. Samples were analyzed for isopropyl alcohol and the metabolite acetone.


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Following gavage exposure to 2 or 4 ml/kg, maximum blood levels of 147 and 282 mg/dl, respectively, of isopropyl alcohol were measured. Concentrations of acetone rose steadily over the 4 h period and were 74 and 73 mg/dl following exposure to 2 or 4 ml/kg, respectively. The authors stated that the maximum levels of isopropyl alcohol observed in this experiment, correlated with inebriation and near coma in the animals. Following inhalation and dermal exposure, the concentration of isopropyl alcohol in the blood continued to rise and was 112 mg/dl at 4 h while the concentration of acetone was 19 at 4 h. Inhalation exposure with a plastic barrier between the soaked towel and the chest resulted in isopropyl alcohol and acetone blood levels of <10 mg/dl. The researchers concluded that isopropyl alcohol is absorbed by the dermal route but that prolonged dermal exposure (i.e. repeated sponging or soaking for several hours) would be required to produce significant toxicity. From CIR final report on Methyl Acetate179

Subchronic Inhalation Toxicity Fischer 344 rats and CD-1 mice (10/sex/group) were exposed via inhalation to 0, 100, 500, 1500, or 5000 ppm (0, 246, 1230, 3690, or 12,300 mg/m3) isopropyl alcohol for 6 h/day, 5 days/wk for 13 weeks.206 Ataxia, narcosis, hypoactivity and the lack of a startle reflex were observed during exposure at 5000 ppm. Hypoactivity was observed in animals exposed to 1500 ppm isopropyl alcohol. At 13 weeks, no gross lesions were observed. Microscopic examination of control and 5000 ppm exposed animal tissues showed hyaline droplets within the kidneys of male rats only. The size and frequency of the droplets was increased in the treated group. The authors concluded that the NOAEL for this study was 500 ppm and the lowest-observable adverse effect level (LOAEL) was 1500 ppm based upon clinical signs and changes in hematology at 6 weeks. To evaluate the neurobehavioral effects of isopropanol exposure, an additional 15 rats/sex were exposed (via inhalation) to 0, 500, 1500, or 5000 ppm (0, 1230, 3690, or 12,300 mg/m3) for 6 h/day, 5 days/wk for 13 weeks. Isopropyl alcohol did not produce any changes to the parameters of the functional observations battery which was conducted at 1, 2, 4, 9 and 13 weeks. Clinical signs observed in mice, during the exposure, included ataxia, narcosis, hypoactivity and lack of a startle reflex at 5000 ppm. Narcosis, ataxia and hypoactivity were observed in animals exposed to 1500 ppm isopropyl alcohol. At 5000 ppm, increased body weight and increased rate of weight gain were observed in female mice. At 13 weeks, no gross lesions were observed and no treatment-related microscopic changes were observed. A 10% and 21% increase in relative liver weight was observed in female mice at 1500 and 5000 ppm, respectively. The authors concluded that the NOAEL for this study was 500 ppm and the LOAEL was 1500 ppm based on clinical signs and increased liver weights. Ocular Irritation

Isopropyl alcohol has been labeled a severe ocular irritant based on rabbit ocular irritation tests.207 From CIR final report on Methyl Acetate179

Reproductive and Developmental Toxicity

Female Sprague-Dawley rats (25/group) were exposed to 0, 400, 800, or 1200 mg/kg bw/day isopropyl alcohol via gavage on gestational days (GD) 6 through 15.208 Female New Zealand white rabbits (15/group) were exposed to 0, 120, 240, or 480 mg/kg bw/day isopropyl alcohol via gavage on GD 6 through 18. Animals were observed for body weight, clinical effects and feed consumption and the fetuses examined for body weight, sex and visceral and skeletal alterations at GD 20 for rats and GD 30 for rabbits. In rats, 2 dams died at the 1200 mg/kg bw dose and 1 dam died at the 800 mg/kg bw dose. Maternal gestational weight gain was reduced at the highest dose tested. No other effects were observed on maternal reproductive health. Fetal body weights at the two highest doses were decreased statistically. No evidence of teratogenicity was observed at any dose. In rabbits, four does died at the 480 mg/kg bw dose. Treatment related clinical signs of toxicity were observed at the 480 mg/kg bw dose and included, cyanosis, lethargy, labored respiration and diarrhea. No treatment related findings were observed at GD 30. Decreased feed consumption and maternal body weights, at 480 mg/kg bw, were statistically significant. No other effects were observed on maternal reproductive health. No evidence of teratogenicity was observed in the rabbits at any dose. The authors determined NOAELs for both maternal and developmental toxicity of 400 mg/kg bw, each, in rats and 240 and 480 mg/kg bw, respectively, in rabbits. From CIR final report on Methyl Acetate179

Carcinogenicity

Fischer 344 rats and CD-1 mice (65/rats/sex/group; 55/mice/sex/group) were treated via inhalation with 0, 500, 2500, or 5000 ppm (0, 1230, 6150, or 12,300 mg/m3) isopropyl alcohol for 6 h/day, 5 days/wk for 104 weeks in rats and 78 weeks in mice.206 An additional 10/animals/sex/species were treated with these same concentrations of isopropyl alcohol for 6 h/day, 5 days/wk for 72 weeks in rats and 54 weeks in mice and underwent an interim evaluation. Another 10 mice/sex/group were treated according to the paradigm described above for 54 weeks and then allowed to recover before


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being killed at 78 weeks. Animals were observed and evaluated for body and organ weights, ophthalmology, and clinical and anatomic pathology. In rats, increased mortality due to chronic renal disease was observed at 5000 ppm (both sexes) and at 2500 ppm (males only). Hypoactivity and lack of startle reflex were observed in 2500 ppm treated rats and hypoactivity, lack of startle reflex and narcosis were observed in 5000 ppm treated rats. With the exception of the ataxia, the clinical signs were transient and ceased when the exposure ended. Increases in body weight, body weight gain, and liver weights were observed in 2500 and 5000 ppm treated rats. Chronic renal disease was exacerbated in rats treated with isopropyl alcohol. Male rats had a concentration related increase in absolute and relative testes weights. At the interim euthanasia (after 72 weeks) male rats treated with 5000 ppm had an increased frequency of testicular seminiferous tubule atrophy upon microscopic evaluation. At the terminal euthanasia (104 weeks), male rats had a concentration dependent increase in the incidence of interstitial (Leydig) cell adenomas of the testes at all administered doses. No other tumor types were increased in rats under these treatment conditions as compared to controls. In mice, no differences in mortality were observed between control and treated animals. Hypoactivity, lack of a startle reflex, narcosis, ataxia, and prostration were observed in 5000 ppm treated mice. Hypoactivity, lack of startle reflex and narcosis were observed in 2500 ppm treated mice. Increases in body weight, body weight gain, and liver weights were observed in 2500 and 5000 ppm treated mice. Male mice in all treatment groups had a decrease in relative testes weights, and female mice exposed to 5000 ppm isopropyl alcohol exhibited decreases in absolute and relative brain weights. At the terminal euthanasia (78 weeks) an increased incidence of minimal to mild renal tubular proteinosis was observed in males and females in all treatment groups. Male mice exposed to 2500 and 5000 ppm exhibited an increased incidence of dilation of the seminal vesicles. No neoplastic lesions were observed in male or female mice. The authors reported a NOAEL for toxic effects of 500 ppm for both rats and mice based on kidney and testicular effects.

IARC (International Agency for Research on Cancer) has determined that isopropyl alcohol is not classifiable as to its carcinogenicity to humans (Group 3). From the CIR final report on Methyl Acetate179


According to unpublished data, a 80.74% spray concentrate caused did not exhibit any potential for dermal sensitization in 9 human subjects.194 According to unpublished HRIPT study on 109 test subjects, a 2.85% hair dye base formulation of isopropyl alcohol and a 1.95% isopropyl acetate caused no dermal sensitization in humans.195 The applicability of fluorescence confocal laser scanning microscopy for in situ imaging of irritant contact dermatitis caused by pelargonic acid using 12 healthy individuals (8 males, 4 males; 18 to 64 years old) was studied.196 Using Finn chambers (occlusive patches), the flexor side of the right and left forearm was exposed to 60 µl of 10% (w/v) pelargonic acid in isopropanol solution and isopropanol vehicle. Isopropanol was used as a control. The Finn chambers were removed at 24 h post-application and reactions were scored according to the following scale: 0 (no visible reaction) to 4+ (intense erythema with bullous formation). Reactions were not observed at sites treated with isopropanol. From the CIR final report on Methyl Acetate179

Hexyl Alcohol – metabolite of Dihexyl Adipate Ocular Irritation Undiluted hexyl alcohol has been labeled as highly irritating on rabbit ocular irritation tests.209 Dermal Sensitization In a maximization test using guinea pigs, hexyl alcohol was not a sensitizer at 1% in petrolatum.209 Caprylic Alcohol – metabolite of Dicapryl Succinate, Dicapryl Adipate and Dicaprylyl/Capryl Sebacate Dermal Irritation – Animals Caprylic alcohol applied full strength to intact or abraded rabbit skin produced a mild irritation.182


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Clinical Irritation and Sensitization Tested in at a concentration of 2% in petrolatum, caprylic alcohol produced no irritation in a 48 h closed-patch test in 25 human subjects.182 Isobutyl Alcohol – metabolite of Diisopropyl Adipate and Diisopropyl Sebacate Subchronic Inhalation Toxicity

Rats (10/sex/group) were exposed via inhalation to isobutyl alcohol vapor concentrations of approximately 0, 770, 3100, or 7700 mg/m3, for 6 h/day, 5 days/week, for 14 weeks.210 The functional observational battery was conducted along with endpoints of motor activity, neuropathology and scheduled-controlled operant behavior. A slight reduction in responsiveness to external stimuli was observed in all treated groups during exposure. This effect resolved upon cessation of exposure to isobutyl alcohol. From the CIR final report on Methyl Acetate179

Ethylhexyl Alcohol – metabolite of Diethylhexyl Succinate, Diethylhexyl Adipate and Diethylhexyl Sebacate Absorption, Distribution, Metabolism, and Excretion In vitro dermal absorption rates were determined for ethylhexyl alcohol in rats and humans. In rats, the rate was 0.22 mg/cm2/h and in the human it was 0.038 mg/cm2/h.211 Accordingly, the human rate of ethylhexyl alcohol absorption was 5.78 times slower than in the rate in the rat. Acute Dermal Toxicity In three different acute dermal toxicity studies on rabbits with ethylhexyl alcohol, the LD50 values reported were 2380, greater than 2600 and greater than 5000 mg/kg body weight.211 Repeated Dose Dermal Toxicity Rats (10) were dosed 2 ml/kg body weight/day (1600mg/kg/day) via single application on shaved backs.211 Absolute and relative thymus weights, liver granulomas, brochiectasis in the lung, renal tubular epithelial necroses, edematous heart and testes, and spermatogenesis, all decreased. Rats (10/sex) were dosed 0, 500, or 1000 mg/kg body weight/day (5 days occlusive, 2 days untreated, 4 days treated).211 500 and 1000 mg treated rats exhibited minimal exfoliation, decreased spleen weight and increased serum triglycerides in females. Ocular Irritation Instillation of 20 µg of ethylhexyl alcohol into the conjunctival sac of rabbits caused moderately severe irritation of the cornea.209 Dermal Irritation – Animals Ethylhexyl alcohol was applied under occlusion to the skin of 3 male rabbits for 4 hours and found to be irritating.209 In another study with rabbits, 0.5 ml of ethylhexyl alcohol was applied under occlusion on intact skin for 1, 2, 4, and 24 hours. Irritation was considered high, and effects seen after 7 days were not reversible. Reproductive and Developmental Toxicity A group of female rats was exposed for 7 h per day to 850 mg/m3 of ethylhexyl alcohol on gestation days 1-19.209 Dams were sacrificed at day twenty. Ethylhexyl alcohol reduced maternal feed intake, but did not produce any malformations. The estrogenic activity of 2-ethylhexanoic acid was examined using an E-SCREEN assay using T47D human breast cancer cells.212 Weak estrogenic activity was observed. (Additional details were not provided.) Genotoxicity In vitro, ethylhexyl alcohol was negative in a number of Ames assays, a liquid suspension assay, mouse lymphoma assay, and unscheduled DNA synthesis assay.117,138,139,142,150 In a 3H-thymidine assay, there was a dose-dependent inhibition of 3H-thymi-dine into replicating DNA, with a dose-dependent increase in the ratio of acid-soluble DNA incorporated into the thymidine.139 The urine of rats dosed orally with 1000 mg/kg bw ethylhexyl alcohol was not mutagenic.149 In vivo, ethylhexyl alcohol was not genotoxic in a mouse micronucleus test or a transformation assay.150


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Carcinogenicity B6C3F1 mice (50/sex/group) were administered 0, 50, 200, or 750 mg/kg body weight/day via gavage, 5 days/week for 18 months.211 At the 750 mg dose, weak hepatocellular carcinoma increased in females, body weight gain decreased and mortality increased. F344 rats (50/sex/group) were administered 0, 50, 150, or 500 mg/kg body weight/day via gavage, 5 days/week for 24 months. Rats dosed at 150 mg and greater were characterized with body weight gain decrease, lethargy and unkemptness. At 500 mg, mortality in females was at 52%. Clinical Irritation and Sensitization Tested in at a concentration of 4% in petrolatum, ethylhexyl alcohol produced no irritation in a 48 h occlusive-patch test in 29 male volunteers.211 In a maximization study, ethylhexyl alcohol did not induce any sensitization reactions. MEHA , Mono-(2-Ethyl-5-Hydroxyhexyl)Adipate, Mono-(2-Ethyl-5-Oxohexyl)Adipate - metabolites of Diethylhexyl Adipate Genotoxicity MEHA was not mutagenic in an Ames assay at concentrations of ≤100085 or 10,000 µg/plate.138 Mono-2(ethyl-5- hydroxy-hexyl)adipate and mono-(2-ethyl-5-oxohexyl)adipate, were not mutagenic in an Ames assay at concentrations of ≤1000 µg/plate.85 Isooctyl Alcohol – metabolite of Diisooctyl Adipate and Diisooctyl Sebacate Subchronic Oral Toxicity In a subchronic gavage toxicity study of a mixture of C7-9, branched alkyl alcohols in rats, a NOEL of 125 mg/kg bw/day and a lowest-observed effect level of 250 mg/kg bw/day were determined.117 Reproductive and Developmental Toxicity In an oral gavage developmental toxicity study of a mixture of C7-9, branched alkyl alcohols in rats, a maternal NOAEL of 500 mg/kg bw and a fetal NOAEL of 1000 mg/kg bw were reported.209 Genotoxicity A mixture of C7-9, branched alkyl alcohols were not mutagenic in in vitro bacterial and mammalian cell assays.209 Carcinogenicity Ethylhexyl alcohol was not oncogenic in rats dosed, via gavage, with 0, 50, 150, or 500 mg/kg bw, in an aqueous vehicle with 0.005% Cremophor EL.209 Isononyl Alcohol – metabolite of Diisononyl Adipate Reproductive and Developmental Toxicity In an oral gavage developmental toxicity study of a mixture of C8-10, branched alkyl alcohols in rats, maternal and fetal NOAEL values were each reported to be 144 mg/kg bw. 209 Isodecyl Alcohol – metabolite of Diisodecyl Adipate Reproductive and Developmental Toxicity In an oral gavage developmental toxicity study of a mixture of C9-11, branched alkyl alcohols in rats, a maternal NOAEL of 158 mg/kg bw and a fetal NOAEL of 790 mg/kg bw were reported. 209 Isostearyl Alcohol – metabolite of Diisostearyl Glutarate, Diisostearyl Adipate and Isostearyl Sebacate Clinical Irritation and Sensitization

The skin irritation potential of lsostearyl Alcohol was evaluated in 19 male and female subjects (18-65 years old) at a concentration of 25.0% in petrolatum. The test substance did not induce skin irritation in any of the subjects (Primary Irritation Index = 0.05). In three similar studies, three different lipstick products containing 25.0, 27.0, and 28.0%


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Isostearyl Alcohol, respectively, were tested according to the same protocol. The three products did not induce skin irritation. The irritation and sensitization potential of Isostearyl Alcohol (25% v/v in 95.0% isopropyl alcohol) was evaluated in 12 male subjects (21-60 years old). Challenge applications were made to original and adjacent sites 2 weeks after removal of the last induction patch. Three of 12 subjects had slight erythema during induction, and there was no evidence of sensitization. The sensitization potential of a pump spray antiperspirant containing 5.0% Isostearyl Alcohol was evaluated using 148 male and female subjects. The product was applied via an occlusive patch to the upper arm for a total of nine induction applications (3 times/week for 3 weeks). Each patch remained for 24 h, and sites were scored immediately before subsequent applications. During the challenge phase, a patch was applied to the induction site and to a new site on the opposite arm of each subject. Reactions were scored 48 and 96 h after application. Ten of the twelve subjects with reactions suggestive of sensitization were re-challenged with the product 2 months later. Patches remained for 24 h, and sites were scored at 48 and 96 h post-application. Six subjects had reactions during the re-challenge. Four of the six subjects were then tested with 5.0% Isostearyl Alcohol in solution with ethanol 6 weeks after scoring of the first rechallenge; all had positive responses. Negative responses were reported when the product (without lsostearyl Alcohol) and 100.0% ethanol each were tested. In a second study, the same product was applied to 60 male and female subjects (same protocol). Five of the subjects had positive responses after the first challenge. One of the five was re-challenged with 5.0% Isostearyl Alcohol in ethanol solution, and a positive reaction was observed. From the CIR final report on Isostearyl Alcohol197

Isopropanol Comedogencity An LDLo of 2-4 ml/kg of isopropyl alcohol has been reported in adults and 6 ml/kg (9 ml/kg 70% isopropyl alcohol) was reported to induce coma in children.


Personal Care Products CouncilCommitted to Safety,Quality & Innovation

Memorandum

TO: F. Alan Andersen, Ph.D.Director - COSMETIC INGREDIENT REVIEW (CIR)

FROM: John Bailey, Ph.D.Industry Liaison to the CIR Expert Panel

DATE: October 13, 2010

SUBJECT: Concentration of Use - Diisobutyl Succinate and Diisobutyl Glutarate

Diisobutyl Succinate and Diisobutyl Glutarate were included in a Council concentration of use survey.No uses of these ingredients were reported.

11011 7th Street, N.W., Suite 300 Washington, D.C. 20036-4702 202.331.1770 202.331.1969 (fax) www.personalcarecouncil.org CIR Panel Book Page 181

Personal Care Products CouncilCommitted to Safety,Quality & Innovation

Memorandum

TO: F. Alan Andersen, Ph.D.Director - COSMETIC INGREDIENT REVIEW (OR)

FROM: John Bailey, Ph.D.JE_Z I3( 1(.)Industry Liaison to the CIR Expert Panel

DATE: August 23, 2010

SUBJECT: Comments on the Draft Report on Dicarboxylic Acids and their Salts and EstersPrepared for the August 30-31, 2010 CIR Expert Panel Meeting

General comment: The EPA HPV submissions should be rechecked for more details. If the followingwebsite is used http://www.epa.gov/hpv/hpvis/index.html (use the search box on the rightlabeled “Start here to look up data on a high production volume chemical”) to search for CASnumbers, more detailed summaries can be found. More study details are also found in therobust summaries which follow the short narrative summary. Some specific examples ofstudies included in the CIR report for which more details are available are provided in thecomments below. When citing a secondary source, such as the HPV and OECD robustsummaries, it would be helpful to state the year in which the study was completed, as thisinformation will not be in the reference section if only a secondary source is cited.

General comment: How is CIR defining subchronic and chronic durations of exposure. Generally,chronic exposure is considered to be durations of 1 year or more, but this report includes a 6month study in the chronic exposure section.

p.1 - The second “isostearyl sebacate” in the list of esters needs to be changed to “diisostearylsebacate”.

p.4 - Please add the compound (Dibutyl Adipate) for which the UV absorption spectrum was provided.p.5, 51 - It is not clear why Dipotassium Azelate, Disodium Sebacate and Di-C12-15 Alkyl Adipate are

listed as exceptions. These ingredients are in the EU Inventory of Cosmetic Ingredients (see theCosing database at http://ec.europa.eu/consumers/cosmetics/cosingl). It would be better to saythat the ingredients are in the EU inventory, rather than “listed for use by the European Union(EU) without restriction.”

p.6 - Please correct the spelling of “succynil-CoA”p.7 - In the summary of the C9 to C12 Dicarboxylic Acids section, please indicate how long after

dosing the dicarboxylic acids were recovered unchanged in the urine.p.8 - In the summary under Azelaic Acid, please include the duration of exposure for the dermal

studies.p.10 - In the description of the human study of Disodium Sebacate, it is not clear what is meant by

“amount of sebacate expired in carbon dioxide”.

1101 17th Street, N.W., Suite 3O0 Washington, D.C. 20036-4702 202.331.1770 202.331.1969 (fax) www.personalcarecouncil.org CIR Panel Book Page 182

p.10 - Was there a radioactive label in the rat study of Disodium Dodecanedioate?

p.1 1 - Over what time period did 70% of the Azelaic Acid diffuse into the reservoir solution?p.13 - More details on the 90-day rat and dog studies of Glutaric Acid are available from the EPA HPV

website (see:http ://iaspub.epa. gov/oppthpv/Public Search.PublicTabs ?SECTION= 1 &epcount=2&v rs list=25040546,25040553 and description above about how to use the HPV search website). Thesestudies are dietary studies. The summary provides the following information about the methodsused in the rat study. “The test method was similar OECD Guideline 408 with someexceptions. Fifteen males and 15 females per test group were used. Food consumption wascalculated for 5 males and 5 females per group. Body weights, mortality and reactions wererecorded. Hematology (hct, rbc, hgb, tot. & diff. leuk), blood chemistry (BUN, SAP, SGPT,GLU), and urinalysis (glu, alb. pH, spec. g, micros. elements) were recorded for 5 males and 5females from the high dose group (2%) and control group (0%) at 45 and 84 days on test.Organ weights and ratios (brain, liver, kidneys, spleen, gonads, heart) from all survivors wererecorded at terminal sacrifice. Histopathology was conducted on 40 tissues/organs for 10 malesand 10 females from the high dose group (2%) and control (0%) group. Gonads were examinedgrossly, weighed, and preserved in formalin solution. Microscopic examination of 10 rats fromthe control and 2% dose groups were conducted. The testes, seminal vesicle, ovary, and uteruswere stained (hematoxylin and eosin).” Similar details are available for the dog study (understudy 2).

p.13 - From the description of the 19 week dietary study of Sodium Adipate, it is not clear if the robustsummary of this study was reviewed. In the OECD HPV reports, the robust summaries followthe narrative summary of all the studies. At the highest dose (3400 mg/kg bw/day) slightintestinal irritation and slight effects were seen on the liver. It is not clear where the statementthat the NOAEL was 3333 mg/kg came from (see p.126 of the OECD report).

p.14- - When the report states that animals were fed diets containing x mg/kg, it is not clear if thismeans x mg/kg diet, or x mg/kg body weight. This is a concern for the 180 day oral study ofAzelaic Acid and the 6 month oral study of Disodium Sebacate.

p.14- - In the summary of the Ocular Irritation section, it would be helpful to indicate that theingredients were tested undiluted.

p.15 - More details of the Glutaric Acid dermal irritation study are available athttp ://iaspub.epa. gov/oppthpv/Public Search .PublicTabs ?SECTION= I &epcount= I &v rs list=25040540 - 3 rabbits were tested with 100 mg powder for 24 hours. “Scores of P11=35.2/110.0were reported. Copious discharge, moderate erythema and edema, mild eversion of lids, andiritial dullness were observed during the 1st hour. Mild erythema, slight edema, and slightdullness remained at the final reading after 7 days.”

p.16, 53 - In the summary of the Reproductive and Developmental Toxicity section, please state thatthe study showing an “inhibitory effect on the uterine horn” was an in vitro study, and that theeffect was on muscle activity.

p.16 - It would be helpful to note that reference 73 is an abstract.p.17 - Were the doses in the rabbit studies of Azelaic Acid and Disodium Sebacate mg/kg diet or

mg/kg body weight?p.18 - What are the units for the following “Sodium succinate, 10 /plate”?

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p.19 - See p.81 of the HPV summary documenthttp://www .epa.govfHPV/pubs/summaries/dicarbx/c 13108 .pdf for more details of themicronucleus cytogenetic assay of Glutaric Acid in mice. It says: “Two groups of animals (11weeks old) were given a single intraperitoneal injection at 800 mg/kg and sacrificed at 30 or 48hours. Two additional groups of animals were given 2 injections of 800 mg/kg at 0 and 24hours and sacrificed at 48 or 72 hours, respectively, after the first dose. Similar groups, servingas the positive and negative control, were evaluated concurrently. The positive control wasadministered as a single dose of triethylenemelamine (TEM), and the animals were sacrificed at30 hours. The negative control animals were administered 2 injections of distilled water at 0and 24 hours, and these animals were sacrificed 48 hours after the initial dose. Slides wereprepared from the bone marrow of the femurs of each animal in the assay and stained. Codedslides were scored for the number of polychromatic erythrocytes (PCE) with micronuclei in1000 PCE.” “Glutaric acid did not produce a statistically significant increase in micronuclei inany of the treated groups, and was determined to be negative in this assay.”

p12 - In the summary of the Diethyl Malonate dermal penetration information, please include the studydurations.

p.22 - The following sentence does not make sense. “In the receptor fluid, 20-21% of the applied dosewas present as hydrolysis products.” Previously it states: “At 24 h, 0.2-0.6% of the diethylmalonate was found in the receptor fluid”. If only 0.2-0.6% was in the receptor fluid, howcould 20-21% of the applied dose be present as hydrolysis products? Perhaps 20-21% refers tothe percentage of the material found in the receptor fluid.

p.23 - In the summary of Ditridecyl Adipate dermal penetration, please include the study durations.p.29 - In the Diethylhexyl Sebacate subsection, “2% diethylhexyl adipate” should be changed to “2%

diethylhexyl sebacate”.p.30 - Please provide the dose or concentration range at which Dibutyl Sebacate was studied in human

KB cells, monkey Vero cells and dog MDKC cells.p.31, 54 - In the summary of the Short-Term Oral Toxicity section, please change “administration of

10% in feed killed 5/5 female mice” to “5/5 female mice fed 10% in the feed died.” As foodintake was decreased at 10%, the deaths may have not have been a direct result of DiethylhexylAdipate.

p.33 - What was the duration of the dietary study of Diethyl Malonate in rats? Were the dosesprovided mg/kg diet, or mg/kg body weight?

p.33 - In the 90-day dietary study of Diethylhexyl Adipate in rats were the doses (0-4740) mg/kg diet ormg/kg body weight?

p.34 - Were the doses in the 13 week rat study of Diisononyl Adipate mg/kg diet or mg/kg bodyweight?

p.34 - In the summary of the Subchronic Dermal Exposure section, please provide the frequency(2x/week) of the dermal application of Dibutyl Adipate to dogs.

p.35 - At the end of the Chronic Oral Exposure section, it would be helpful to state that additionalchronic studies are presented in the Carcinogenicity section.

p.35 - Why is there a separate Inhalation section for the inhalation study of the mixture? This studyshould be presented in the Acute Exposure section in an inhalation exposure subsection.

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p.36 - In the description of the Diisopropyl Sebacate study, “rabbits” needs to be added after “NewZealand white”.

p.37 - The verb is missing from the following sentence. “The skin of 4 animals abraded.”p.39 - In the summary of the Reproductive and Developmental Toxicity section, “branched and linear

alkyl esters of adipic acid” is stated twice. In the summary, please include the species that weretested (the species are missing from the end of the first paragraph and the second paragraph).

p.41 - What dose(s) of Ditridecyl Adipate “affected” (decreased?) mean fetal body weights and crown-rump lengths?

p.41 - Please describe the gross abnormalities observed in the i.p. study of Diisobutyl Adipate. Was adevelopmental NOAEL identified for Diisobutyl Adipate?

p.42 - Please list the hormones that were measured in rat study of Diethylhexyl Adipate.p.44 - Unless effects on hormones were determined, please move the description of the effects on

reproductive tissues in dogs in the 13-week study of Diisononyl Adipate to the Reproductiveand Developmental Toxicity section.

p.4-5 - In the summary of the Genotoxicity section, it would be helpful to state that additional details ofthe studies are provided in Table 11.

p.46 - Pleas change “indicating that it is not converted to metabolic urinary metabolites” to “indicatingthat Diethylhexyl Adipate is not converted to mutagenic urinary metabolites” (as the sentence iscurrently structure “it” refers to urine).

p.4-6 - In the summary of the Carcinogenicity section, it would be helpful to indicate that the NTP studywas a dietary study. It would be helpful to use the same units in the summary and theCarcinogenicity section (currently the summary says 2.5% and the Carcinogenicity section says25,000 ppm).

p.4-7 - Please provide the range of concentrations of Diethylhexyl Adipate tested in formulation.p.4-7 - What concentration of Diethylhexyl Adipate was associated with erythema and papules when

applied under occlusion for extended periods of time?p.51 - In the Summary, it would be helpful to list the six dicarboxylic acids and salts that are used and

the 24 esters that are used.p.52 - Please indicate if the spennicidal effect of Malonic Acid was observed in vitro.p.53 - Please include the durations of the in vitro pig skin study of Diethyl Malonate, the in vivo studies

of Diethyl Malonate and the oral study of Diethylhexyl Adipate in rats.p.55 - Please provide the species in the Diethylhexyl Adipate study of testicular effects, the

Diethylhexyl Sebacate reproductive and developmental study and the dermal study of DitridecylAdipate.

p.56 - Please provide the species and doses used in the Diethylhexyl Adipate study reporting endocrine-mediated effects.

p.59, Reference 44, p.60, Reference 67 - As the URLs are the same, references 44 and 67 appear to bethe same reference.

p.139-143 (CIR Panel Book pages), Table 1 - Please provide a reference for this table.p.144-14-8, Tables 2a and 2b - For those values that were not estimated using EPI Suite, please provide

references.

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p.153 - It is not yet appropriate to include Diisobutyl Succinate and Diisobutyl Glutarate in the list ofingredients not reported to be used as the concentration of use survey on these two ingredientshas not yet been completed.

p.154, Table 4 - In the row under Inhalation for Adipic Acid, why are the units mg/L in the Dosecolumn and mg/m3 in the media lethal dose/conc. column?

p.163, Table 9-As the EpiOcular study is in vitro, the title of the Animals column should be changedto “Animals/System” - EpiOcular MTT viability assay should be in the system column andundiluted should be in the procedure column.

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Personal Care’ Products CouncilCommitted to Safety,Quality & Innovation

Memorandum

TO: F. Alan Andersen, Ph.D.Director - COSMETIC INGREDIENT REVIEW (CIR)

FROM: John Bailey, Ph.D.Industry Liaison to the Cifi Expert Panel

DATE: October 4, 2010

SUBJECT: Comments on the Tentative Report on Dicarboxylic Acids and their Salts and Esters

Cover sheet - Why are there two covers and two titles on this report?It would be helpful to include the abstract in the tentative report so the public has the opportunity to read the

abstract and provide comments.p.1 - Dibutyl Glutarate is not in the Dictionary. Please change Dibutyl Glutarate to Diisobutyl Glutarate.p.2 - Please look at the published re-review reports for Diethylhexyl Adipate and Diisopropyl Adipate.

The CIR Expert Panel re-reviewed these ingredients once. Somehow the re-review gotpublished twice. The concentration of use information is the same in both published versions.

p.6, 52 - Please change “European Union (EU) inventory” to European Union (EU) inventory ofcosmetic ingredients”.

p.8-9 - In the Adipic Acid section, including the summary, please provide the durations of the studies.p.10 - In the summary of the Disodium Sebacate section, please provide the duration of the studies.p.12 - Please indicate the source (species) of skin that was used in the in vitro percutaneous study of

Azelaic Acid.p.13 - Please provide the compounds that had the LD50 values of 0.94 g/kg and 11 glkg.p.14, 15 - For the inhalation study in which rats were exposed to 126 mg/rn3 Adipic Acid and mice

were exposed to 13 or 129 mg/rn3,please indicate that this was a “dust”.p.15 - The only 2-year study presented in reference 65 (EPA HPV summaries) is the published study by

Maekawa et al. (1990) (reference 68 in this report). More details of this study are presented inthe Carcinogenicity section of this report. This was a drinking water exposure study. Thisstudy should be cited to the primary reference, as it is cited in the Carcinogenicity section.

p.16, Table 5 - The description of the eye irritation studies of Adipic Acid does not accurately reflectthe information that was in the EPA HPV summaries. The results of these studies as given inthe EPA summary is copied below.

“Ten mg of adipic acid produced no corneal and a minimal iritic effect with a mildconjunctival irritation. At 7 days, there was a minimal conjunctival irritation, and theeye was normal within 14 days. An eye dosed with 10 rng of the compound andpromptly washed had mild conjunctival irritation with no corneal or iritic effect, andwas normal within 3 days. Adipic acid (57.1 mg of powder) produced mild opacity of

11011 7th Street, N.W., Suite 300 Washington, D.C. 20036-4702 202.331.1770 202.331.1969 (fax) www.personalcarecouncil.org CIR Panel Book Page 187

the cornea with minimal iritic effect and moderate to mild conjunctival irritation. Theeye was normal at 7 days. An eye dosed with 57.1 mg of the compound and promptlywashed produced a transient, mild opacity with no iritic effect, and a moderate to mildconjunctival irritation. The eye was normal within 3 days.”

p.18 - One 4-hour exposure is not long enough to determine whether or not Dodecanedioic acid is asensitizer. In what species was this study completed?

p.20 - Although few details were provided in the summary, the SIDS report on Dodecanedioic Acid didindicate that the reproductive study of Dodecanedioic Acid was an OECD combined repeateddose and reproductive/developmental toxicity screening test. Details of the protocol can befound in the guideline for this method. It also stated that compound related effects were limitedto mild decreases in lymphocyte counts.

p.20 - In the summary of the Genotoxicity section, please change “mg/mg” to “mg/mi”. As the system(Chinese hamster fibroblast cells) is given in the summary, it should also be stated below in theDisodium Succinate subsection.

p.28 - In the following sentence, for what was the rate of formation calculated? “The rate of formationwas calculated, since there was not evidence of diethyihexyl adipate absorption, as 1.63 ± 1.19hr1.”

p.29 - Please revise the following sentence. “A statistically significant increase in 8-OH-dG wasincreased in the liver DNA, but not the kidney DNA, at wk 1 and 2.”

p.30, 54 - The meaning of the following sentence is not clear. “Mostly, acute exposure via inhalationto diethyl rnaionate, dibutyl adipate, and diethyihexyl sebacate did not result in death of rats.”What were the exposure concentrations?

p.30 - The 14-day dietary study of Diethyihexyl Adipate from the original CIR report (cited to the NTPreport) is the same as the “new” 14-day study cited to reference 113. Reference 113 indicatesthe original report is a 1976 unpublished study completed at Mason Research Institute. Theintroduction to the NTP report indicates that the studies were done at E & G Mason ResearchInstitute (the chronic study was completed during 1977-1979).

p.32 - Based on the units of mg/rn3,the exposure of 4 rats, 2 guinea pigs, 2 rabbits and 1 cat toDiethylhexyl Sebacate appears to be an inhalation, rather than a dermal exposure study, andshould not be presented in the dermal exposure section.

p.32 - The 13-week study of Diethylhexyi Adipate in rats and mice study cited in the original reportand the 13-week study of Diethylhexyi Adipate cited to reference 117 (which may be an errorand should be 113) are the same study. Both the original CIR report and reference 113 cite thisstudy to the NTP report.

p.34 - Why does the acute inhalation exposure study of the mixture of Dimethyl Glutarate, DimethylSuccinate and Dimethyl Adipate warrant a separate section? This study should be included inthe Acute Exposure section and the details of the study should be in Table 9 under inhalationexposure.

p38 - Please look at reference 14 again (p.16 1-162). There are more details available on the Buehlerguinea pig sensitization study of Dimethyl Malonate. The study was done via OECD method406, the induction and challenge concentrations were 100%, and there were 10 guinea pigstested and 20 controls.

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p.39 - In the summary of the Reproductive and Developmental toxicity section, please indicated if fetalbody weights and crown-rump lengths in the Ditridecyl Adipate rat study were increased ordecreased (it currently says “affected”).

p.39 - Please revise the following sentence. “An increase in post-implantation loss was increased inthe 100 mg/kg bw group, resulting in a statistically significant decrease in the number of livepups.,,

p.42 - Although the authors may not have defined it, LH is luteinizing hormone.p.42 - Please revise the following: “...and until day 7 of gestation day.”p.43 - As rats have relatively short gestation periods, “109” in the following sentence is likely “19’.

“Exposure was discontinued from day 109 of gestation through day 3 post-partum.”p.49 - Please provide the number of subjects used in the Phototoxicity and Photosensitization studies of

Dibutyl Adipate, Diisopropyl Adipate and Diethylhexyl Adipate. As the Dibutyl Adipateinformation also came from a CW report, it should have a statement similar to those providedfor Diisopropyl Adipate and Diethylhexyl Adipate (or those statements should be removed).

p.53 - Please state the signs of toxicity observed in mice exposed to 460 mg/rn3 Adipic Acid.p.53 - Please indicate that spermicidal activity of Malonic Acid was observed in vitro.p.55 - Please move the 4-hour inhalation study of the mixture so that it is discussed with the other acute

inhalation studies.p.55 - Please provide the concentrations that were irritating and not irritating to the eyes.p.55-56 - The last paragraph on p.55 (that ends on p.56) appears to summarize the dermal irritation and

sensitization studies, but skin or dermal is never stated. Please provide the concentrations thatwere not sensitizing. In what species were the phototoxicity studies of the perfumeformulations completed?

p.56 - Please revise the following. “Oral administration of 7000 mg/kg bw di-C7-9 branched andlinear alkyl esters of adipic acid branched and linear alkyl esters of adipic acid to SpragueDawley rats did not result in developmental toxicity.”

p.56 - Please provide the assay type in which the genotoxicity results were equivocal.p.57 - Please indicate that the irritation and sensitization studies summarized on this page are clinical

studies.p.57 - As they arrived at similar conclusions, please present the IARC and the EPA cancer

classifications of Diethylhexyl Adipate together.p.57 - Where are the data that indicate that dicarboxylic acids are “not appreciably absorbed”? On p.12

there is an in vitro study of Azelaic Acid that found that 70% diffused into the reservoirsolution over 48 hours.

p.57 - Where is the information to support the following statement? “Any uses as a fragranceingredient are at concentrations too low to produce irritation.”

p.58 - The paragraph concerning potential transmission of BSE and viruses is inconsistent with currentFDA policy. The Federal Register: September 7, 2005 (Volume 70, Number 172) states:

“The exemption of tallow derivatives from the definition of “prohibited cattle materials”does not depend on the source tallow for the derivatives. For the reasons discussed inthe preamble to the interim final rule, tallow derivatives present a negligible risk oftransmitting the agent that causes BSE regardless of the source tallow. Therefore, alltallow derivatives are exempt from the ban on the use of prohibited cattle materials in

3


human food and cosmetics.”The paragraph is also inconsistent with international guidelines. The 2010 Terrestrial AnimalHealth Code of the World Organization for Animal Health (OiE) at

http://www.oie.intJenJnormes/mcode/en chapitre 1.11.5 .htm lists “tallow withmaximum level of insoluble impurities of 0.15% in weight and derivatives made fromthis tallow” under the heading “Safe Commodities” that “should not require any BSErelated conditions, regardless of the BSE risk status of the cattle population of theexporting country, zone or compartment”.

Based on OiE code, it would be appropriate to state that tallow derivatives which may be usedto make some of the ingredients included in this report must be made from tallow containing amaximum level of insoluble impurities of 0.15% in weight.

The paragraph as currently written implies that some of these ingredients may be derived fromhumans, which is not correct. Please do not include “human” or “Human ImmunodeficiencyVirus (HIV)” when discussing these ingredients.

Abstract, Discussion, Conclusion - Please include the list of all the ingredients included in the report ineither the Abstract, Discussion or Conclusion as these sections of the report are put into theCompendium without the rest of the report.

Figure 1 - As the report that includes Isopropyl and Propyl Alcohols is now final with a conclusion ofsafe as used, these ingredients can now be placed in a box consistent with other ingredients withsafe as used conclusions.

Table 1 - Please include the reference with this table.Tables 2a and 2b - Please include references with these tables.Table 4 - For the oral study of Sodium Succinate, why are the units g/kg under dose and mg/kg under

median lethal dose?Table 4 - Please check the EPA (2001) rat value for the mixture of Adipic/Glutaric/Succinic Acids as a

high dose of 2000 mg/kg is more common than a dose of 200 mg/kg.Table 9 - The 4-hour inhalation study of Dimethyl Glutarate, Dimethyl Succinate and Dimethyl

Adipate should be added to this table.

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sebacic acid/dicarboxylic acids

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