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IAQA 2018 Annual Meeting
Presenter Company Logo Steve Froelicher, PhD, Senior Scientist
Prism Analytical Technologies
s.froelicher@pati-air.com
Office Number (989)-772-5088
Fundamentals of Formaldehyde
and Formaldehyde Analysis
2019 IAQA Annual Meeting
Formaldehyde
➢Formaldehyde is the simplest organic molecule containing C, H, and O
➢Formaldehyde is highly reactive
➢Formaldehyde sources are both natural and man-made
➢Formaldehyde exposure is an indoor air quality problem that is frequently overlooked
2019 IAQA Annual Meeting
Formaldehyde
➢This presentation will discuss the impact of formaldehyde on indoor air quality, its sources, and how it can be measured.
➢Acceptable levels in indoor environments will be discussed along with methods to help reduce these levels.
2019 IAQA Annual Meeting
What is Formaldehyde and Why Do We Care
➢ First described in 1855 by Russian scientist
Butlerow
➢ Colorless gas;
➢MW 30; simplest C, H, O molecule
➢ Highly reactive molecule; very versatile for formation of
resins (e.g., phenol-formaldehyde); UF insulation
➢Questions regarding carcinogenicity began in 1980;
phenol – formaldehyde resins began being phased out
(insulation; building materials)
2019 IAQA Annual Meeting
More about Formaldehyde
➢ Formaldehyde (and Acetaldehyde (CH3CHO)) are
present in our bodies as a result of biochemical
processes➢ Formaldehyde formed in “one-carbon cycle”; cellular growth
results in HCHO formation….this is toxic to DNA…instead of
attacking DNA…it is instantly converted into formate ions that
promote further cellular growth
➢ Acetaldehyde…responsible for “hangovers”…created by enzyme
destruction of excess ethanol; excess acetaldehyde is the
primary reason we feel nauseous.
➢ Primary concern: Inhalation
2019 IAQA Annual Meeting
What Encompasses Indoor
Air Quality?
Occupant Comfort(Temperature,
Humidity)
CO, CO2
Particulate-Lifestyle(Skin Cells, Dander, Textile
& Paper Fibers, Smoke)
Particulate-Building(Fiberglass, Corrosion,
Rust)
Volatile Organic
Compounds
(VOCs)
Mold(Spores, Mycotoxins,
MVOCs, Debris)
Indoor
Air
Quality
RadonAllergens
(Pet Dander, Dust
Mites)
2019 IAQA Annual Meeting
Air Quality Statistics
➢VOCs in indoor air 2-5 times higher than outdoor air (EPA)
➢Certain activities may increase VOCs to 1,000 times higher than outdoor air (EPA)
➢Indoor VOCs in winter 3-4 times higher than summer
2019 IAQA Annual Meeting
Causes - Recent Changes
➢Energy efficient building construction
➢Leakage eliminated; traps VOCs in breathing zone
➢Active ventilation is needed
➢Synthetic materials (general increase in VOCs due to MOC (materials of construction))
➢Amount of time spent indoors has increased
➢OVERALL AFFECT: Increase in respiratory conditions
2019 IAQA Annual Meeting
Ventilation ➢ Ventilation concerns (new vs. old homes)
➢ Many older homes are lower in VOCs and
formaldehyde
2019 IAQA Annual Meeting
Situations With IAQ Concerns/Formaldehyde concerns
➢Buying new home
➢Health; VOCs from new construction➢Formaldehyde from adhesives; laminates; coatings
➢ Lumber Liquidators; Weyerhaeser joist coatings
➢Odor
➢Mold
2019 IAQA Annual Meeting
Situations With IAQ Concerns/formaldehyde concerns
➢Change in situation
➢New baby; inferior products containing OSB or other laminates/glues containing formaldehyde
➢New product (e.g., furniture); inferior product construction, especially cabinetry
➢Renovation; glues/adhesives
➢Event (e.g., structural fire); Combustion is a source of formaldehyde; includes fireplace usage
2019 IAQA Annual Meeting
Challenge: Everyone is Different
➢ Depend on:
➢ Specific VOC or type of VOC
➢ Level of exposure
➢ Length of exposure
➢ Individual’s sensitivity
➢ Health Effects
➢ Eye and respiratory irritation, dizziness, headache,
nausea, etc.
No Effect → Irritating → Highly Toxic
www.epa.gov/iaq/voc.htmltoxtown.nlm.nih.gov/text_version/chemicals.php?id=31
2019 IAQA Annual Meeting
What are the Sources of HCHO?
Natural Sources: Wood
Man-Made Sources: Resins; adhesives;
laminates
Combustion Processes (can be
considered a natural source also; forest
fires, etc.)
2019 IAQA Annual Meeting
Sources – Formaldehyde
2019 IAQA Annual Meeting
Sources – Formaldehyde
➢ pine wood
➢ Slow release of formaldehyde; cellulose degradation
2019 IAQA Annual Meeting
Sources – Formaldehyde
➢ Present in many construction materials
➢ Engineered hardwood and bamboo laminate flooring
➢ Cabinetry (urea formaldehyde resins – can off-gas
significantly)
➢ Plywood and OSB (phenol formaldehyde resins – tend
to off-gas less)
➢ Insulation (glass and foam – both urea and phenol
formaldehyde types used)
➢ Produced by combustion sources
➢ Methane (natural gas) converts to formaldehyde due to
incomplete combustion
➢ Furnace, unventilated combustion sources, fireplace,
tobacco smoke
2019 IAQA Annual Meeting
Sources – Formaldehyde
➢ Significant levels found in new or newly renovated homes
➢ Levels
➢ Outdoor: 1-20 ng/L
➢ Indoor: 20-60 ng/L
➢ Symptoms
➢ Causes numerous respiratory issues
➢ Common: irritation of throat, nose, eyes, skin;
exacerbate asthma
➢ Classified as Group 1 carcinogen (IARC): carcinogenic
to humanswww.cdc.gov/nceh/ehhe/trailerstudy/pdfs/08_118152_compendium-for-states.pdfmonographs.iarc.fr/ENG/Monographs/vol100F/mono100F-29.pdf
2019 IAQA Annual Meeting
Consider Health Effects:Range of Particle Sizes for Pollutants
➢ Formaldehyde diameter ~ 0.0001 um
➢ VOCs typically too small in diameter to be trapped by traditional
filtration devices (carbon bed adsorbents needed)
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Health Effects –
Formaldehyde
2019 IAQA Annual Meeting
Health Effects –
Formaldehyde
2019 IAQA Annual Meeting
Interesting Dilemma: Product Formulations Containing Formaldehyde
➢ In the presence of water, formaldehyde is in equilibrium with methylene glycol (different CAS Number)
➢ Methylene glycol exists in hair conditioning products (heavily used in hair salons)
➢ Methylene glycol considered nonhazardous
CAS 50-00-0 CAS 463-57-0Hazardous generally nonhazardous
2019 IAQA Annual Meeting
Formaldehyde/Methylene Glycol Equilibrium
2019 IAQA Annual Meeting
How is Formaldehyde Detected?
DNPH Method
2,4-dinitrophenylhydrazine
Not specific to formaldehyde; requires chromatographic separation
Hantzsch Method
in situ generation of fluorescing agent
Very specific for formaldehyde (minor interferences)
Photoacoustic infrared spectroscopy
Mid-IR fundamental spectral absorption line of formaldehyde
Highly specific for formaldehyde
2019 IAQA Annual Meeting
DNPH Method
Requires cold storage
Formaldehyde is derivatized in the DNPH tube
Requires Cold packing and shipping
2019 IAQA Annual Meeting
DNPH Method
The DNPH method for formaldehyde requires a
chromatographic separation.
The method will detect other interfering species
such as aldehydes and ketones
2019 IAQA Annual Meeting
Hantszch Reaction
• In situ derivatization of formaldehyde
• liquid phase reaction of formaldehyde with
acetyl-acetone (2,4-pentadione) and ammonia.
• This reaction produces 3,5-diacetyl-1,4-
dihydrolutidine (DDL) (absorbs light at 410 nm;
fluoresces at 510 nm.
2019 IAQA Annual Meeting
Instrumentation
AL 4021 Aero Laser Fluorimeter
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Instrumentation
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Potential Interferences are Minimal
minimally sensitive to other aldehydes and ketones
Benzaldehyde < 1 : 20000 Glyoxal < 1 : 123 Butanol < 1 : 900
NO < 1 : 300000 CH3CHO < 1 : 10000 Methanol < 1 : 50000
HNO3 < 1 : 1000 NO2 < 1 : 500000 Acrolein < 1 : 10000
H2O2 < 1 : 100 Acetone < 1 : 300000 SO2 < 1 : 300000
Propanal < 1 : 20000 O3 < 1 : 800 Isobutane < 1 : 300000
2019 IAQA Annual Meeting
Comparison of Methods
Prism TDT Method NIOSH 2016 using DNPH
Formaldehyde collection Adsorption onto thermal desorption
tube
Derivatization on cartridge at testing location
Derivatization Reaction Hantzsch Reaction in situ in instrument
prior to detection
Dinitrophenyhydrazone Reaction on cartridge
Formaldehyde Detection Fluorescence using fluorimeter UV using HPLC separation method
Shipping Method Ambient (no special precautions) Shipped on Ice
Minimum detection limit 0.030 ug (30 ng) 0.1 ug (100 ng)
Volume sampled 4 – 6 L 15 L
Working Range 5 ng/L - ~ 2400 ng/L 15 ng/L – 2450 ng/L
2019 IAQA Annual Meeting
Comparison of Methods
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Photoacousic Spectroscopy
Uses the Mid-IR fundamental spectral absorption line of formaldehyde
Highly specific for formaldehyde
Experimental methods currently under development
2019 IAQA Annual Meeting
Results from ~ 6900 Samples
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Concentration Units
Concentration: normalized amount of chemical
substance
ng/L nanogram per liter
mg/m3 microgram per cubic meter
mg/m3 milligram per cubic meter
ppm parts per million
ppb parts per billion
Conversions
1 ng/L = 1 mg/m3 = 0.001 mg/m3 or 1 mg/m3 = 1000 mg/m3
1 ppm = 1000 ppb or 1 ppb = 0.001 ppm
Need molecular weight to convert
1 ng/L of Benzene * 24.04 / 78 = 0.3 ppb Benzene
2019 IAQA Annual Meeting
Definitions & Meanings
Exposure Limit: concentration below which workers will not generally
experience adverse effects
PEL: Permissible Exposure Limit
REL: Recommended Exposure Limit
TLV: Threshold Limit Value
IDLH: Immediately Dangerous to Life or Health
Concentration below which escape without injury or irreversible health
effect
TWA: Time Weighted Average
Typically 8 hour work day in 40 hour work week
C: Ceiling
May not be exceeded at any time
ST or STEL: Short Term Exposure Limit
Typically 15 minute period
Ca: potential occupational Carcinogen
Exposure Limits:
2019 IAQA Annual Meeting
Exposure Guidelines and Limits = CONFUSION!!!
Different organizations have posted different limits of
exposure and consumers and professionals alike are
confused by what the real limits are.
• NIOSH lists the lowest limit of 16 ppb for
occupational recommended exposure limit (REL)
• Ambient air can be 5-20 ppb depending on
location
2019 IAQA Annual Meeting
Exposure Guidelines and Limits = CONFUSION!!!
• Most organizations suggest 80-100 ppb and 40-50 ppb
for short term and long term exposures, respectively
• OSHA has established a workplace permissible exposure
limit (PEL) of 940 ng/L (750 ppb)….THIS IS LAW
2019 IAQA Annual Meeting
Exposure Limits – Residential No requirements for residential buildings
Guidelines for green homes
LEED for businesses (37 ug/m3)
4 hr testing (DNPH); other testing devices being
considered
Recommendations available from some states for
select compounds
Formaldehyde
Large range – from 8 ppb to 100 ppb
CA CREL (Chronic Reference Exposure Levels)
www.oehha.ca.gov/air/Allrels.html
Vapor intrusion guidelines
2019 IAQA Annual Meeting
What is CARB-2 Testing?
California Air Resources Board (CARB)
NOTE: CARB-2 testing is for product compliance
• CARB-2
• Short-hand term for airborne toxic control measure
(ATCM) to reduce formaldehyde emissions from wood
products
• Phase 2; 93120 refers to sections in the California
Code of Regulations.
• CARB-2 specifies a primary method ASTM E1333-96
(2002) – large chamber testing method
• ASTM has a small scale chamber version as well
(ASTM D6007-02)
2019 IAQA Annual Meeting
CARB-2 Testing
Typical emission standards for different wood
materials:
• 50 ppb – hardwood/plywood veneer core
• 50 ppb – hardwood/plywood composite core
• 90 ppb – particleboard
• 110 ppb – Medium density Fiberboard (MDF)
• 130 ppb – thin MDF
2019 IAQA Annual Meeting
CARB-2 Testing vs. Room Testing
Often there is confusion regarding CARB-2 Testing
results vs. Room Testing Results
CARB-2 Testing if for one specific laminated board heated in a
chamber under very controlled temperature and humidity
conditions.
Room Testing uses a sampler such as a thermal desorption
tube….represents a “snap-shot” in time of the formaldehyde
concentration in a room from “ALL” sources of formaldehyde
…the results of room testing are dependent on factors of
temperature, humidity, and ventilation rates
2019 IAQA Annual Meeting
Case ScenariosCase 1: Laminate board does not pass CARB-2 testing (i.e.,
material emissions are elevated)
• Installed in home
• Temperature and humidity are relatively low
• Air flow is relatively high
• Room testing of formaldehyde may lead to relatively low number
relative to CARB-2 test results
Case 2: Laminate board passes CARB-2 testing
• Installed in home
• High temperatures and high humidity
• Poorly ventilated area
• Room testing of formaldehyde is relatively high compared to CARB-
2 test results
2019 IAQA Annual Meeting
Environmental
Conditions➢ Temperature
➢ Higher → more VOCs; higher formaldehyde levels
➢ Lower → fewer VOCs
➢ Humidity
➢ Higher → more VOCs; higher formaldehyde levels
➢ Lower → fewer VOCs
➢ Air Flow
➢ Higher → fewer VOCs; lower formaldehyde levels
➢ Lower → more VOCs
2019 IAQA Annual Meeting
Caution: Whole House Ozonation
➢ Odor issues; Allergens
➢ Ozone generators are used to cleanse the
environment of allergens, smoke particulates,
odors, etc.
➢ Potential Issues:
➢ Ozone creates formaldehyde; ozone attacks
double bonds
➢ Collateral damage to materials of construction
2019 IAQA Annual Meeting
Case Study
➢ Client of an Inspector was not happy with 50 ng/L
formaldehyde in RV
➢ Inspector Ozonated the RV for 24 hrs
➢ Formaldehyde levels climbed to beyond 200 ng/L
after ozonation
➢ Ozone attacks double bonds in MOC and can
result in formaldehyde and an entire series of
aldehydes up to C12 (Dodecanal); VOC results
were also elevated after ozonation
➢ Caution on use of ozone generating machines
2019 IAQA Annual Meeting
Other Air Filtration Technology
➢ Rule number 1 (if feasible):
➢ Remove the source of formaldehyde
➢ Safest filtration technology involves use of a
carbon bed adsorbent
➢ Still many unknowns with PCO technology and
other filtration devices that use destructive
mechanisms for odor and VOC removal
2019 IAQA Annual Meeting
Conclusions
➢ Formaldehyde is everywhere due to presence of natural
resources and man-made resources (building products, etc.
➢ Formaldehyde results in symptoms ranging from
respiratory distress and nasal irritation to exacerbation of
asthmatic conditions.
➢ Various methods can be used for detecting formaldehyde,
including DNPH, the Hantzsch Reaction; and Photoacoustic
Infrared spectroscopy
2019 IAQA Annual Meeting
Acknowledgements
Alice Delia, Analytical Laboratory
Manager, Prism
Contact information:Steve Froelicher – Prism Analytical Technologies
s.froelicher@pati-air.com 989-772-5088
2019 IAQA Annual Meeting
Useful Online Resources
ATSDR: Agency for Toxic Substances and Disease Registry www.atsdr.cdc.gov/
IRIS: Integrated Risk Information System www.epa.gov/iris/index.html
TOXNET: Toxicology Data Network toxnet.nlm.nih.gov/
Can search multiple databases
NIOSH: National Institute for Occupational Safety and Health www.cdc.gov/niosh/
CARB: California Air Resources Board www.arb.ca.gov
US EPA Indoor Air Quality (IAQ) www.epa.gov/iaq/
Household Products Database householdproducts.nlm.nih.gov/index.htm
2019 IAQA Annual Meeting
Questions?
Steve Froelicher
s.froelicher@pati-air.com
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