organic carbon chemistry in the valley atmosphere

Organic Carbon Chemistry in the Valley  Atmosphere: Quinones and Peroxides 

Alam

Hasson

Department of Chemistry

California State University, Fresno

Quinones and Peroxides are minor components of PM

Polyaromatic

Hydrocarbons (PAH)

Quinones

Hydrogen Peroxide (H2

O2

)

Annual Average PM2.5

~25 g.m‐3 

Typical mass loading for quinones

and PAH < 1 ng.m‐3 (0.004% of PM 

mass) Typical mass loading for H2

O2

* < 30 ng.m‐3

(0.1% of PM mass)(*

for

Southern

California)

O

O

OO

O

O

O

O

OH

OH

O2. ‐ H2

O2

Atmos.Ox. ?

Fe3+

Fe2+

Reducing Agent

.OH

O2. ‐O2

CellDamage

Reducing AgentReducing AgentPrimary 

Emissions

Also present 

in PM

Key Questions to address:1.

Do all quinones

behave the same?2.

What is the relative importance of emissions vs. chemistry?3.

What is the relative importance of H2

O2

production in atmosphere vs. in lung?

Quinones and Hydrogen Peroxide

Hydrogen Peroxide Generation in the  Atmosphere

Hydrogen Peroxide in PM

• Fine aerosols contain high concentrations of liquid water, so H2

O2

may 

partition between the gas phase and the aerosol according to Henry’s law:

Organics

Emissions

OxidationHO2 + Other Products

H2 O2Self Reaction

Uptake intoAqueous Aerosol

H2 O2 (g) H2 O2 (l) HA .PH2O2 = [H2 O2 ]aq

Hydrogen Peroxide• H2

O2

levels are up to 100 

times higher in PM than 

expected in LA basin.

5/8 5/13 5/18 5/23 5/28 6/2 6/70

2

4

6

8

10

12

14

Aerosol Phase H2O2

Aero

sol H

2O2 /

ng

m-3

Date

0.5

1.0

1.5

2.0

2.5

3.02 2

Gas Phase H2O2

Gas Phase H

2 O2 / ppb

2.0x10-9 4.0x10-90.0

1.0x10-3

2.0x10-3

3.0x10-3

HA x [H

2O

2]gas

= [H2O

2]liquid

[H2O

2] aero

sol /

M

[H2O

2]gas

/ atm.

• Measurements imply that H2

O2

is generated 

within the particles themselves.

• Metals and/or organics (including quinones) 

may undergo reactions to form H2

O2

in 

particles.

(Hasson

and Paulson, J. Aerosol Sci, 459‐68, 2003.)

Endo‐

vs. Exo‐ROS Generation

1E-7 1E-6 1E-5 1E-4 1E-31E-8

1E-7

1E-6

1E-5

1E-4

1E-3ApproximateRange ofAmbient H2O2

Measurements

Approximate Range ofAmbient QuinoneMeasurements

H2O

2 Pro

duct

ion

Rat

e / M

hr-1

[Quinone]aerosol / M

Lower Limit Upper Limit

(Ascorbate‐only Chemistry)

Hydrogen peroxide in PM may

be as important as hydrogen peroxide formed by PM.

O

O

O

O

5,12‐NaphthacenequinoneAnthraquinone

O O

Acenaphthenequinone

OO

PhenanthraquinoneO

O

1,4‐Naphthoquinone

O

O

1,2‐Naphthoquinone

O

O

1,4‐Chrysenequinone

O

O

2,6‐Dtb‐1,4‐Benzoquinone

H3C

O

O

2‐Methyl Anthraquinone

H3C

O

O

H3C

2,3‐Dimethyl Anthraquinone

O

O

Benz[a]anthracene‐7,12‐dione

Quinones Identified in Fresno Air:Do they all behave in the same way?

DTT (Dithiothreitol) Assay

• Provides information on the potential of PM extracts to cause cell injury.

• Quinones/PM oxidize DTT, generating H2

O2

.

•

The reaction rate is correlated with bronchial epithelial cell injury by ROS (Li 

et al., Environ. Health Perspect. 2003).

HO

HOSH

SHHO

HOS

SHO

HOS

S

O

O

R1

R2

R4

R3

O

O

R1

R2

R4

R3

O

O

R1

R2

R4

R3

O

O

R1

R2

R4

R3

O2.‐ O2

.‐

O2 O2

O2H2O2

DTT (Dithiothreitol) Assay

0.0 2.0x10-6 4.0x10-6 6.0x10-60.0

1.0x10-6

2.0x10-6

3.0x10-6

4.0x10-6

5.0x10-6

Slope = 0.75 +/- 0.15 min-1

R2 = 0.74P = 6 x 10-4

Mea

sure

d R

ate

/ M.m

in-1

Calculated Rate / M.min-1

Rate = k’PQ

[PQ]0

+ k’1,4‐NQ

[1,4‐NQ]0

+ k’1,2‐NQ

.[1,2‐NQ]0

Measured quinones account for all of the reactivity of the PM samples collected.Phenanthraquinone dominates the reactivity of these samples.

Origins of Atmospheric Quinones: Emissions vs. Chemistry

Sources of Quinones and PAH

• Samples Collected at Fresno 

State (November 2005 – June 

2006).

• Lundgren Impactor

with four 

size cuts (10, 3, 1 and 0.3 m).

• ~50 chemical compounds 

monitored.

Sources of Quinones and PAH: 11/2005 –

7/2006

Gasoline vehicles

Wood CombustionDiesel

Vegetation

Road Dust

Meat Cooking0.0

0.2

0.4

0.6

0.8

1.0

R-V

alue

Gasoline vehicles

Wood CombustionDiesel

Vegetation

Road Dust

Meat Cooking

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

P-Va

lue

Wood Combustion

Gasoline vehiclesDiesel

Vegetation

Road DustMeat

0.0

0.2

0.4

0.6

0.8

1.0

R-V

alue

Wood Combustion

Gasoline vehiclesDiesel

Vegetation

Road DustMeat

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

P-Va

lue

Wood combustion correlation is strongly dependent on a few data points.

PAH and quinone

mass loadings are strongly correlated (R2

= 0.98; P = 2 x 10‐4).

Quinones

PAH

Some Quinones Expected From PAH Oxidation  Chemistry

• PAH oxidation chemistry is 

complicated.

• Quinones have been observed in  low yield (a few percent or less) 

from several PAHs.

• Because PAH emissions are much 

greater than quinone

emissions, 

chemical formation of quinones

in 

the atmosphere may exceed 

primary emissions.

(Lee and Lane, Atmospheric Environment, 43, 4886‐93, 2009.)

Evidence for Photochemistry from Southern  California

• Role of photochemistry estimated from relative levels of phenanthrene, 

phenanthraquinone

and benzo[g,h,i]perylene.• ~90% of phenanthraquinone

is from phenanthrene

oxidation.

(Eiguren‐Fernandez et al, Atmospheric Environment, 42, 2312‐19, 2008.)

PM in Southern and Central California not the same

Jan

Feb MarApri

lMayJu

ne Jul

Aug Sep OctNov Dec

0

10

20

30

40

50Av

erag

e PM

2.5 M

ass

Load

ing

/ g.

m-3

San Joaquin Valley Los Angeles Basin

Jan

FebMarApri

lMayJu

ne Jul

AugSep OctNovDec

0

10

20

30

40

50

Mass Loadings for 2009 (California Air Resources Board)

6/17/2

008

6/20/2

008

6/23/2

008

6/26/2

008

6/29/2

008

7/2/20

087/5

/2008

7/8/20

087/1

1/200

87/1

4/200

87/1

7/200

8 --

0

20

40

60

80PM

2.5 /

g.m

-3

0.0

2.0x105

4.0x105

6.0x105

Levo

gllu

cosa

n / A

U

0.05.0x104

1.0x105

1.5x105

2.0x105

Phe

nant

hren

e / A

U

No Phenanthraquinone

observed: Not present or all in the gas phase?

Field Data –

Summer 2008

Summer A

Summer

B

Field Data –

Summer 2004

6/8/2004

6/14/2004

6/16/2004

6/18/2004

6/20/2004

6/22/2004

6/24/2004

6/26/2004

6/28/2004

6/30/20047/2/2004

7/4/20047/6/2004

0

1

2

3

4

5

6

7

8

9

10

Mas

s Lo

adin

g / n

g.m

-3

Date

Anthraquinone Naphthacenequinone

A A

A

A A

A

BBBBBBB

Daytime vs. Nighttime Chemistry

• OH and O3

are the major daytime oxidants; NO3

is the  main nighttime oxidant.

Gas Phase Phenanthraquinone

from Phenanthrene

Gas Phase Reaction with

OH NO3 O3

Yield 3% 33% 2%

Reaction Rates(cm3.mol‐1.s‐1)

3.2 x 10‐11 1.2 x 10‐13 4.0 x 10‐19

Formation Rate(pg.m‐3.hr‐1)

80 800 0.2

(Wang et al, Atmospheric Environment, 41, 2025‐35, 2007.)

Daytime vs. Nighttime Quinone

Levels

6-Mar

7-Mar

8-Mar

9-Mar

12-M

ar13

-Mar

14-M

ar15

-Mar

16-M

ar19

-Mar

20-M

ar21

-Mar

22-M

ar23

-Mar

0

5

10

15

20

25

Mas

s Lo

adin

g / n

g.m

-3

Central Fresno (Day) Fresno State (Day) Fresno State (Night)

Fresno State

Central Fresno

Chrysenequinone

• Samples collected at both sites 6:00 am – 6:00 pm. Samples also collected at Fresno State 

site 6pm – 6 am.• Chrysenequinone, Phenanthraquinone

and 1,2‐Naphthoquinone levels were higher during 

day (although not statistically significant).

Conceptual Model for Secondary PM Formation

Inversion Layer

PhotooxidationProducts (e.g., Nitrate)

Primary Emissionse.g., NOx

Primary Emissions

PhotooxidationProducts (e.g., Nitrate)

(Watson and Chow, Atmospheric Environment, 36, 177‐201, 2002.)

Summary

• Certain quinones

such as 

phenanthraquinone

likely 

play a greater role in ROS 

production than others.

• Some evidence for quinone

production from chemical 

reactions, but more work is 

needed to understand this.

• Hydrogen Peroxide in 

atmospheric particles may 

play an important role in 

particle chemistry and health 

effects, but levels and origins 

are not well understood.

Acknowledgements

Akihiro Ikeda

Kennedy Vu

Akiteru

Ikeda

Julie Lyon

Enrique Lopez

Rick Lazaro

Dora Rendulic

Mark Sorenson

Christina Sabado

Dianne Lim

Joscelyn

Jackson

Saddam Muthana

Rodhelen

Paluyo

Denise Soria

Juan Camacho

Dr. Myeong

Chung

Dr. Thomas Cahill (UC Davis)

Tim Tyner (UCSF‐Fresno)

Funding

San Joaquin Valley Air Pollution Control District

College of Science and Mathematics and the Provost’s Office, California State 

University, Fresno