Continuous Analysis of Fresno Aerosols by Size, Time, and Elemental Concentrations, March – December, 2001 Thomas A. Cahill, Steven S. Cliff, Michael Jimenez-Cruz,

Continuous Analysis of Fresno Continuous Analysis of Fresno Aerosols by Size, Time, and Aerosols by Size, Time, and Elemental Concentrations,Elemental Concentrations,

March – December, 2001March – December, 2001

Thomas A. Cahill, Steven S. Cliff, Michael Thomas A. Cahill, Steven S. Cliff, Michael Jimenez-Cruz, and Jimenez-Cruz, and 11Kevin D. Perry, Kevin D. Perry,

DELTA Group, University of California, Davis, DELTA Group, University of California, Davis, http://delta.ucdavis.eduhttp://delta.ucdavis.edu and and

11Dept. of Meteorology. University of UtahDept. of Meteorology. University of Utah

Purpose of the StudyPurpose of the StudyFresno, California, has one of the highest

childhood asthma rates in California.

Fresno also is in violation of state and federal air quality criteria –

Ozone, PM10 in summer

PM10 and PM2.5 in winter

To what degree does Fresno air pollution impact the short term childhood asthma rate?

0

0.5

1

1.5

2

2.5

Valu

es

Rela

tive t

o B

utt

e a

nd

Sh

asta

Ischemic Heart Mortality Annual PM10 Childhhod Asthma

Health and Aerosols in the Central Valley of CaliforniaData Relative to Shasta and Butte counties

Get a wide variety of aerosol transition metals as a function of size and time to support short term medical data for the Fresno

Asthmatic Children’s Environment Study (FACES)

Original design: PM10 and PM2.5, day – night, 2 stage DRUMNot possible: Mis-sizing by too few cut points (coarse); Too much loading (accumulation mode); loss of sub-0.25 μm particles

Final design:8 size modes 10.0 μm to 0.09 μm

Why? EPA/IMPROVE 8 DRUM QA; very fine modes;

3 hr time resolutionWhy? Identification of sharp metal concentration episodes

Consequence: Needed to examine over 1500 time periods, 12,000 samples,

and yielding over 1/3 million S-XRF elemental values; but … $$$

Design of the StudyDesign of the Study

6 6 6 6 6 7 7 7 7 7 7 8 8 8 8 8

June, 2002 July, 2002 August, 2002

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5

10

15

20

25

30

35

Mic

rog

ram

s/m

3

PM 2.5 mass PM 2.5 mass (sum of species)

Fine aerosols at the Sequoia NP IMPROVE site

Oregon forest fires

6 6 6 6 6 7 7 7 7 7 7 8 8 8 8 8

June, 2002 July, 2002 August, 2002

0

5

10

15

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25

Mic

rog

ram

s/m

3

Elemental carbonSoil

Organic aerosolsAmmonium nitrate

Ammonium sulfate


Oregon forest fires

11 11 11 12 12 12 12 12 1 1 1 1 1 2 2 2

November, 2002 December, 2002 January, 2003 February, 2003

0

5

10

15

20

25

30

Mic

rogr

ams/

m3

Elemental carbon

Soil

Organic aerosols

Ammonium nitrate

Ammonium sulfate


511

1723

295

1117

2329

410

1622

284

1016

2228

September October November December

0

10

20

30

40

Mic

rogra

m/m

3

SacramentoFresno

CorcoranBakersfield

Fog days at Fresno x 5, no rainRain prev 5 days, Fresno

24 hr Nitrate AerosolsFall, 2002

Wind Bay Area to Bakersfield

Wind Bakersfield to Bay Area

Rain 3 mm

Cold, down-slope

Hot, up-slope

Here there be cows

.

.

ImplementationImplementation• Sampling: a PM10 modified DELTA Group

slotted DRUM impactor, with size cuts at 10, 5, 2.5, 1.15, 0,.75, 0.56, 0.34, 0.26, and 0.09 μm aerodynamic diameter (Raabe-Marple values).

• Analysis: Synchrotron x-ray fluorescence (S-XRF) at the DELTA Group x-ray microprobe of the Advanced Light Source, Lawrence Berkeley National Laboratory.

• Quality Control: – Routine re-analysis of previously analyzed samples,– Comparison with side by side Dichot samplers,– Re-analysis of ARB Dichot samples,– Comparisons with IMPROVE PIXE, XRF.

DELTA Group slotted 8 DRUM DELTA Group slotted 8 DRUM ImpactorImpactor

• 8 size ranges:• 10.0 to 5.0 μm (std PM10 inlet)• 5.0 to 2.5 μm• 2.5 to 1.15 μm• 1.15 to 0.75 μm• 0.75 to 0.56 μm• 0.56 to 0.34 μm• 0.34 to 0.26 μm• 0.26 to 0.09 μm

• 16.7 l/min, critical orifice control, ¼ hp pump

• 10.0 x 168 mm Mylar strips• For 42 day run, 4 mm/day, S-XRF beam 0.5 mm, = 3 hr.• Field portable

• 10 kg, 43 cm × 22 cm × 13 cm

43

cm

Stage 8 of DRUM , 0.26 > DStage 8 of DRUM , 0.26 > Dpp > 0.09 > 0.09 µm µm

diameter, showing strong diurnal pattern; diameter, showing strong diurnal pattern; the deposit shown covers 3 weeks.the deposit shown covers 3 weeks.

DELTA Group Synchrotron-XRF DELTA Group Synchrotron-XRF Facility at the LBNL Advanced Light Facility at the LBNL Advanced Light

SourceSource

For scale? (At least it’s not duct tape.)

Typical S-XRF Spectrum Typical S-XRF Spectrum Raw data, Teflon substrate with no blank subtractionRaw data, Teflon substrate with no blank subtraction

Energy (keV)4 8 12 160

1

10

100

1000

10,000

100,000

Cou

nts

Na 150

100

14

Si 6 23 3S 4 20 3V 1 6 0.1Ni 0.9 0.9 0.2As 1.7 0.5 0.1Sr 2.3 1.3 0.3Cd 7.6 NA NABa 84 NA 1.0Pb 4 2 0.6

RT

I X

RF

IMPR

OV

E

S-X

RF

MDL values(ng/cm2)

Nic

kel

Pot

assi

um

Van

adiu

mM

anga

nes

e Iron

Cop

per Zin

c

Bro

min

eR

ub

idiu

mFlu

orin

e

Su

lfu

r

Ars

enic

an

d L

ead

Cal

ciu

m

Str

onti

um

0 5 10 15 20 25

ARB Dichot ng/m3

0

5

10

15

20

25

AR

B R

AA

S n

g/m

3Fresno FACES Filter Intercomparison

ARB Dichot vs ARB RAASZinc

0 5 10 15 20 25

DELTA Group S-XRF ng/m3

0

5

10

15

20

25

AR

B D

ich

ot,

AR

B R

AA

S n

g/m

3

ARB Dichot ARB RAAS

DELTA S-XRF vs ARB Dichot and ARB RAAS FiltersZinc

All filters S-XRF

vs ARB XRF

1.02 0.11

vs ARB RAAS

1.29 0.58

ARB XRF vs ARB RAAS

1.29 0.63

DRUM S-XRF vs ARB XRF and ARB RAASDRUM S-XRF vs ARB XRF and ARB RAASnote: it takes 24 6 hr 6 size cuts S-XRF measurements to note: it takes 24 6 hr 6 size cuts S-XRF measurements to

match a single 24 hr PMmatch a single 24 hr PM2.52.5 filter filter

PM-2.5 Zn Concentration vs. Date (6-hour data)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

50.0

3/10/01 3/20/01 3/30/01 4/9/01 4/19/01

ng/

m^

3

DRUM -Zn RAAS-Zn Dichot-Zn

The DRUM sees more soil, almost all The DRUM sees more soil, almost all lying between 2.5 and 1.15 lying between 2.5 and 1.15 µmµm

0 100 200 300 400 500 600

FRM - SASS ng/m3

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100

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Dic

hot, D

RU

M n

g/m

3

Dichot DRUM

Silicon Dichot vs FRM

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11

22

22

33

33

44

44

45

55

56

66

67

77

77

88

88

99

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910

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1111

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1212

1212

Month of the year, 2001

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20

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Mic

rorg

am

s/m

3

PM2.5 Mass, 2001

Aerosols at the Fresno 1st Street Supersite

EPA 24 hr standard

EPA annual standard

1014

1923

2731

48

1216

2024

293

711

1519

2327

15

913

1721

2529

37

11

March April May June July, 2001

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1000

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7000

8000

Na

no

gra

m/m

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PM10 PM2.5

Silicon Aerosols at Fresno during the FACES StudyDRUM Impactor, S-XRF Analysis Data, 6 hr resolution

1216

2024

281

59

1317

2125

292

610

1418

2226

304

812

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2428

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1721

2428

26

1014

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July August September October November December, 2001

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Na

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PM10 PM2.5

DRUM Impactor, S-XRF Analysis Data, 3 hr resolution

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1923

2731

48

1216

2024

293

711

1519

2327

15

913

1721

2529

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11


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500

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Na

no

gra

m/m

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PM10 PM2.5

Potassium Aerosols at Fresno during the FACES StudyDRUM Impactor, S-XRF Analysis Data, 6 hr resolution

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2024

281

59

1317

2125

292

610

1418

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304

812

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Na

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gra

m/m

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PM10 PM2.5


Fireworks

1014

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2731

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2024

293

711

1519

2327

15

913

1721

2529

37

11


0

10

20

30N

an

og

ram

/m3

PM10 PM2.5

Strontium Aerosols at Fresno during the FACES StudyDRUM Impactor, S-XRF Analysis Data, 6 hr resolution

1216

2024

281

59

1317

2125

292

610

1418

2226

304

812

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2428

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1721

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1014

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Na

no

gra

m/m

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PM10 PM2.5


Fireworks

1014

1923

2731

48

1216

2024

293

711

1519

2327

15

913

1721

2529

37

11


0

50

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Na

no

gra

m/m

3

PM10 PM2.5

Copper Aerosols at Fresno during the FACES StudyDRUM Impactor, S-XRF Analysis Data, 6 hr resolution

1216

2024

281

59

1317

2125

292

610

1418

2226

304

812

1620

2428

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913

1721

2428

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1014

18


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Na

no

gra

m/m

3

PM10 PM2.5


1012

1417

1921

2325

2729

312

46

810

1214

1618

2022

2426

291

35

7911

1315

1719

2123

2527

291

35

7911

1315

1719

2123

2527

291

35

7911


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Na

no

gra

ms/

m3

PM10 Chlorine Aerosols at Fresno during FACES

12141618202224262830

135791113151719212324262830

1357911131517192123252729

135791113151719212325272931

24681012141618202224262830

2468101214161820


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Na

no

gra

ms/

m3

PM10 Chlorine Aerosols at Fresno during FACES

1014

1923

2731

48

1216

2024

293

711

1519

2327

15

913

1721

2529

37

11


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Na

no

gra

m/m

3

PM10 PM2.5

Zinc Aerosols at Fresno during the FACES StudyDRUM Impactor, S-XRF Analysis Data, 6 hr resolution

1216

2024

281

59

1317

2125

292

610

1418

2226

304

812

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2428

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1721

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m/m

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PM10 PM2.5


A few observationsA few observations

• Differences summer to winter were extreme• Rapid mass variations were seen over short time

periods (a few hours) in almost every coarse and fine aerosol component, major and minor

• Some transition metals reached high levels during these episodes

• Wide variations in particle size are seen over short periods of time

• A great deal of the soil mass at Fresno is respirable

1516

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34

56

78

910

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November December

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50

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250

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Nan

ogra

ms/

m3

Phosphorus x 10 Sulfur Potassium Zinc x 10

Aerosols at the Fresno First Street Super-siteVery fine (0.26 > Dp > 0.09 micron) elemental concentrations for FACES, CARB

S-XRF analyses via DELTA Group, UC Davis

Very fine aerosols characteristic of Very fine aerosols characteristic of diesels/smoking carsdiesels/smoking cars

1810

5.623.2

1.81

0.560.32

0.180.1

0.0560.032

0.0180.01

Coarse MOUDI Stage Diameter (micrometers) Ultra- Fine

-0.02

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

Mic

rog

ram

s/c

m2

Mass/200Sulfur

LeadZinc x 10

Calcium Phosphorus

For micrograms/m3, times 8.7DELTA Group, S-XRF, UC Davis

Diesel Particles by MOUDI Impactor and S-XRFSample Run # 4, CA Fuel; no grease

PM 2.5

PM 0.25 ?PM 10

Very fine zinc to diesel mass = 1800 1300

U. Minnesota/DRI/UC Davis Diesel U. Minnesota/DRI/UC Davis Diesel Sizing StudiesSizing Studies

1516

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78

910

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November December

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50

100

150

200

250

300

Nan

ogra

ms/

m3

Phosphorus x 10 Sulfur Potassium Zinc x 10

Aerosols at the Fresno First Street Super-siteVery fine (0.26 > Dp > 0.09 micron) elemental concentrations for FACES, CARB

S-XRF analyses via DELTA Group, UC Davis

We see very fine aerosols characteristic We see very fine aerosols characteristic of diesels/smoking cars at Fresnoof diesels/smoking cars at Fresno

Predicted diesel vf/uf mass 11/25 – 12/17, 9 ± 6 µg/m3

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1718

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2728

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34

56

78

910

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November December

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5

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20

Con

cent

ratio

ns/m

3

Mass by soft betas (ug/m3) Zinc by S-XRF (ng/m3)

Very fine (0.26 > Dp > 0.09) Aerosols at Fresno, CA

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78

910

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November December

0

5

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20

25

30

Mas

s ug

/m3

Mass measured Mass predicted based on U. Minn. diesels, CA fuel

Very fine (0.26 > Dp > 0.09) Aerosols at Fresno, CASupersite, First Street, > 1 km from nearest freeway

Nov 25 – Dec. 17, 0.26 to 0.09 μm, measured mass = 4.8 ± 1.0, predicted mass = 6.6 ± 4.8 μg/m3

For total vf mass, estimated via measured mass = 8.8 ± 2.0 μg/m3

Aerosol Information from Particle SizeAerosol Information from Particle Size

0.09 to 0.260.26 to 0.34

0.34 to 0.560.56 to 0.75

0.75 to 1.151.15 to 2.5

2.5 to 5.05.0 to 10.0

Particle aerodynamic diameter in micrometers

0

10

20

30

40

50

60

Nan

ogra

ms/

m3

Zinc x 10

Potassium

Copper x 10

Aerosol size distributions at the Fresno Super-siteNovember 15 - December 22, 2001

Soil, biomass, and diesel/smoking car elements derived elements

Fine particle PM2.5 cut

K soil

K biomass smoke

K diesel and smoking cars

Very fine aerosols

ConclusionsConclusions• Health data at high time resolution needs

matching aerosol data, not long term averages.• We find that there are sharp (order of

magnitude) excursions in transition metal mass of a few hours duration throughout the year.

• There are equally rapid changes in particle size.• Winter time exhibits a high level of very fine

particles associated with diesels and smoking cars even well away from major freeways.

• We have generated an extraordinarily detailed data set on Fresno aerosols of high quality and at a very modest cost.

AcknowledgementsAcknowledgements

• California Air Resources Board – Fresno FACES study

• National Renewable Energy Laboratory – DRI diesel tests

• Department of Energy - Lawrence Berkeley NL and the Advanced Light Source – S-XRF capabilities

• National Science Foundation – ACE-Asia DRUM samplers and development

Documents

Continuous Analysis of Fresno Aerosols by Size, Time, and Elemental Concentrations, March – December, 2001 Thomas A. Cahill, Steven S. Cliff, Michael Jimenez-Cruz,