Organic Carbon Chemistry in the Valley Atmosphere: Quinones and - - PowerPoint PPT Presentation

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 H2O2* < 30 ng.m‐3 (0.1% of PM mass)

(* for Southern California)

O O O O

O O O O OH OH

O2

. ‐

H2 O2 Atmos.

• Ox. ?

Fe3+ Fe2+ Reducing Agent

.OH

O2

. ‐

O2 Cell Damage Reducing Agent Reducing Agent Primary 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 Oxidation

HO2 + Other Products H2 O2

Self Reaction

Uptake into Aqueous 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 6/7 2 4 6 8 10 12 14 Aerosol Phase H2O2 Aerosol H2O2 / ng m

• 3

Date 0.5 1.0 1.5 2.0 2.5 3.0

2 2

Gas Phase H2O2 Gas Phase H2O2 / ppb

2.0x10

• 9

4.0x10

• 9

0.0 1.0x10

• 3

2.0x10

• 3

3.0x10

• 3

HA x [H2O2]gas = [H2O2]liquid

[H2O2]aerosol / M [H2O2]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-3 1E-8 1E-7 1E-6 1E-5 1E-4 1E-3

Approximate Range of Ambient H2O2 Measurements Approximate Range of Ambient Quinone Measurements

H2O2 Production Rate / 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‐Naphthacenequinone Anthraquinone

O O

Acenaphthenequinone

O O

Phenanthraquinone

O 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 HO SH SH

HO HO S S HO HO S 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 O2 H2O2

DTT (Dithiothreitol) Assay

0.0 2.0x10

• 6

4.0x10

• 6

6.0x10

• 6

0.0 1.0x10

• 6

2.0x10

• 6

3.0x10

• 6

4.0x10

• 6

5.0x10

• 6

Slope = 0.75 +/- 0.15 min

• 1

R

2 = 0.74

P = 6 x 10

• 4

Measured Rate / M.min

• 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

G a s

• l

i n e v e h i c l e s W

• d

C

• m

b u s t i

• n

D i e s e l V e g e t a t i

• n

R

• a

d D u s t M e a t C

• k

i n g

0.0 0.2 0.4 0.6 0.8 1.0 R-Value

G a s

• l

i n e v e h i c l e s W

• d

C

• m

b u s t i

• n

D i e s e l V e g e t a t i

• n

R

• a

d D u s t M e a t C

• k

i n g

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 P-Value

Wood Combustion Gasoline vehicles Diesel Vegetation Road Dust Meat

0.0 0.2 0.4 0.6 0.8 1.0 R-Value

Wood Combustion Gasoline vehicles Diesel Vegetation Road Dust Meat

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 P-Value

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

• xidation.

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

PM in Southern and Central California not the same

J a n F e b M a r A p r i l M a y J u n e J u l A u g S e p O c t N

• v

D e c 10 20 30 40 50

Average PM2.5 Mass Loading / g.m

• 3

San Joaquin Valley Los Angeles Basin

J a n F e b M a r A p r i l M a y J u n e J u l A u g S e p O c t N

• v

D e c 10 20 30 40 50

Mass Loadings for 2009 (California Air Resources Board)

6 / 1 7 / 2 8 6 / 2 / 2 8 6 / 2 3 / 2 8 6 / 2 6 / 2 8 6 / 2 9 / 2 8 7 / 2 / 2 8 7 / 5 / 2 8 7 / 8 / 2 8 7 / 1 1 / 2 8 7 / 1 4 / 2 8 7 / 1 7 / 2 8

• 20

40 60 80 PM2.5 / g.m

• 3

0.0 2.0x10

5

4.0x10

5

6.0x10

5

Levogllucosan / AU 0.0 5.0x10

4

1.0x10

5

1.5x10

5

2.0x10

5

Phenanthrene / AU

No Phenanthraquinone

• bserved: 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 6/30/2004 7/2/2004 7/4/2004 7/6/2004 1 2 3 4 5 6 7 8 9 10

Mass Loading / ng.m

• 3

Date Anthraquinone Naphthacenequinone

A A A A A A B B B B B B B

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

• M

a r 7

• M

a r 8

• M

a r 9

• M

a r 1 2

• M

a r 1 3

• M

a r 1 4

• M

a r 1 5

• M

a r 1 6

• M

a r 1 9

• M

a r 2

• M

a r 2 1

• M

a r 2 2

• M

a r 2 3

• M

a r 5 10 15 20 25

Mass Loading / ng.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 Photooxidation Products (e.g., Nitrate)

Primary Emissions e.g., NOx Primary Emissions

Photooxidation Products (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