1. Air toxics measurements in a Seattle neighborhood Doris Montecastro and Hal Westberg Laboratory for Atmospheric Research Dept. of Civil and Environmental Eng. Washington State University Pullman, WA 99164-2910

2. Primary Goals  Characterize ambient air toxics concentrations  Evaluate spatial and temporal variability of ambient air toxics  Evaluate modeled results  Support health effects studies

3. Long Term Goals  Estimate source apportionment (statistical and air quality models )  Assess long term trends  Evaluate effectiveness of air toxics reduction strategies

4. Outline I. Introduction A. Urban Air Toxics B. Common Sources II. Methods A. Site B. Analytical Methods III. Data (2004) IV.Results V.Conclusions and Recommendations

5. Introduction Continuation of the monitoring started in 2000 Seattle is one of the original 4 large cities in the 10-site Pilot Monitoring Project Currently, one of the 23 sites in the National Air Toxic Trends (NATTS) network Neighborhood-scale measurements (0.5 – 4 km 2 ) Volatile organic compound (VOC), carbonyl and PM-10 measurements will be presented (although metals were also measured)

6. Sampling Site: Beacon Hill 24-hr integrated samples collected every 6 th day Duplicates also collected for VOCs and carbonyls

7. Analytical Methods TO–14A (GC with FID/ECD)  benzene  1,3-butadiene  CCl 4  Chloroform  Trichloroethylene (TCE)  Tetrachloroethylene (PCE) TO-11A (DNPH cartridge with HPLC)  Acetaldehyde  Formaldehyde Gravimetric  PM-10

8. Common Sources 1,3-butadienerubber manufacturing processes, combustion, cigarette smoke benzeneindustrial solvent, gasoline, auto exhaust, tobacco smoke chloroformchlorinated water, pulp and paper mills, hazardous waste sites, sanitary landfills TCEdegreasing of metals, dry cleaning PCEdegreasing of metals, dry cleaning acetaldehyde oxidation product of tropospheric photochemistry and microbial degradation of organic materials, fruit and fish preservative, solvent in rubber, tanning and paper industries formaldehydenatural sources, insulating foams, plywood resin, carpet materials, tobacco smoke PM-10natural sources, dust, combustion

9. Daily concentrations at Beacon Hill

10. Results: Summary Statistics 1,3- butadienebenzenechloroformTCEPCEacetaldehydeformaldehydePM-10 Mean 0.0440.3940.0470.0210.0250.7990.86814.913 Median 0.0320.3150.0360.0140.0180.7400.78013.446 Minimum 0.0060.1080.0100.0030.0040.4000.3805.360 Maximum 0.2051.1790.1270.0910.1111.6402.03035.260 n 5960 576059 CI (95.0%) 0.0100.0600.0080.005 0.0660.0951.638 benchmark 0.0180.0460.0080.0370.0290.5080.081 background 0.0050.0460.0080.0040.0030.1270.163

11. Precision S-D ARPD(%)Rep ARPD (%)S/D/R ARSD (%) MDL (ppbv) 1,3-butadiene17.619.213.50.021 benzene8.06.85.70.014 chloroform27.910.517.40.010 TCE24.811.216.10.015 PCE15.17.013.20.012 acetaldehyde 5.50.63.2 0.045 formaldehyde 8.51.64.9 0.108

12. Results: Correlation Coefficients 1,3-butadienebenzenechloroformTCEPCEacetaldehydeformaldehyde benzene 0.8631 chloroform -0.173-0.0251 TCE 0.5930.5990.0421 PCE 0.7670.769-0.0470.7561 acetaldehyde 0.4160.5690.1720.3070.4641 formaldehyde 0.6030.666-0.0690.3800.6280.7841 PM-10 0.6380.6760.1220.4540.6650.6960.770 Chloroform has very poor correlation with other VOCs

13. Results: Chloroform August 25, 2004 [chloroform] = 0.010 ppbv WD = SWS = 6 m/s T = 16C April 9, 2004[chloroform] = 0.127 ppbv WD = NE, NWWS = 2 m/sT = 10C Water reservoir

14. Results: Nov. 5, 2004 (high levels) 1,3-butadienebenzenechloroformTCEPCE acetaldehydeformaldehyde PM-10 0.2051.1790.0200.0610.1111.6402.030 35.260 (ug/m3) T = 4C WS = 5 m/s

15. Results: July 20, 2004 (low levels) 1,3-butadienebenzenechloroformTCEPCEacetaldehydeformaldehydePM-10 0.0060.1080.0190.0030.0040.5500.660 10.670 (ug/m3) WS = 3 m/s T = 18C

16. Trends: 2001 - 2004

17. Conclusions and Recommendations Chloroform does not correlate with the other VOCs, implying a unique source Trends observed in previous years still present  High benzene, 1,3-butadiene, TCE and PCE during winter  High acetaldehyde and formaldehyde during summer Ambient concentrations almost an order of magnitude greater for most species Evaluate spatial and temporal variability Compare with modeled results

18. Acknowledgments John Williamson, WA DOE Lee Bamesberger, WSU LAR Jenny Filipy, WSU LAR Gene Allwine, WSU LAR WA Dept. of Ecology and US EPA for financial support