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Air Toxics in Allegheny County: Sources, Airborne Concentrations, and Human Exposure

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Air Toxics in Allegheny County: Sources, Airborne Concentrations, and Human Exposure AIR TOXICS IN ALLEGHENY COUNTY: SOURCES, AIRBORNE CONCENTRATIONS, AND HUMAN EXPOSURE CMU: Jennifer Logue, Kara Huff-Hartz, Andrew Lambe, Allen Robinson, Neil Donahue, Mitch Small, Cliff Davidson ACHD: Roger Westman, Darrel Stern, Jason Maranche Pitt: Bernie Goldstein 1 Description of the Problem Q Purpose: Characterize air toxics concentrations, sources, and risks in Allegheny County Q Rationale: Large uncertainties still exist regarding sources, exposure, and health risks mostly due to a lack of data Q Context: Time resolution and consistency of these measurements allow for more in-depth analysis than has previously been possible 2 Project Objectives Q AmbientAmbient measurementsmeasurements T BaselineBaseline (ACHD) T IntensivesIntensives (CMU) Q EstimateEstimate healthhealth risksrisks (CMU, Pitt) Q DetermineDetermine sourcesource contributionscontributions (CMU) Q EvaluateEvaluate relativerelative risksrisks (CMU) T LocalLocal vs.vs. regionalregional sourcessources T PittsburghPittsburgh vs.vs. otherother citiescities 3 Monitoring Sites Mobile Dominated Avalon Site Industrial Sites Stowe Downtown Regional Background South Site Fayette 4 Design and Implementation of Project Q Two types of measurements T Baseline Q 4-sites Q 24hr average concentrations Q Measured 1:6 for a year Q Canisters (TO-15 standard) Q Cartridges (TO-11a standard) T Intensives Q 3-sites Q Hourly measurements for 1 to 2 months Q Gas and particle phase measurements 5 Automated Field Instrument Gas Chromatograph Mass Spectrometer/ Flame Ionization Detector (GCMS/FID) Q 1 hour resolution Q 70+ compounds Q Low detection limit(<.2μg/m3) (Millet JGR, 2005) 6 Compounds Measured Toluene Chrysene Chloromethane 2-Butanone (MEK) Benzo[ a]anthracene Quinoline Methyl alcohol Fluorene Benzo[k]fluoranthene Styrene Tetrachloroethene 1,1,2-Trichloroethane Benzene Acenaphthene Chlorobenzene 4-Methyl-2-pentanone (MIBK) Anthracene cyclohexane Naphthalene o-Xylene 1-Propanol Ethylbenzene Chloroform Chloroethane Carbon disulfide p-Xylene Acrylonitrile Methyl-t-butyl either(mtbe) Vinyl chloride 1,2-Dichloroethane 1,2,4-Trimethylbenzene Heptane 1,1-Dichloroethane Isopropylbenzene Ethyl acetate 1,1,1-Trichloroethane Ethylene oxide Trichloroethene Benzo[ b]fluoranthene Phenanthrene 1,1,2,2-Tetrachloroethane Bromochloromethane Methylene chloride Vinyl acetate Pyridine Methyl methacrylate 1,4-Dioxane n-Propylbenzene Bromomethane Acrolein (Propenal) 1,2-Dichlorobenzene Fluoranthene Acenaphthylene Bromoform Pyrene Benzyl chloride m-Xylene 1,4-Dichlorobenzene *Simultaneous measurements of local meteorology and criteria pollutants 7 Measurement Inter-comparison TolueneToluene BenzeneBenzene 12 6 Slope=Slope=1.394 1.4 10 5 Slope=Slope= 1.6 1.6 8 4 6 3 Canister Canister 4 2 (microg/m3) (microg/m3) 2 1 Canister Measurements Canister Measurements 0 0 024681012 0123456 AveragedHourly Measurments Hourly (microg/m3) HourlyAveraged Measurments Hourly (microg/m3) 8 Air toxic concentrations relative to South Fayette 6 5 4 3 2 1 0 Pittsburgh Ratio with Regional Background Styrene Tetrachloroethylene Avalon o-Xylene m & p- Xylene 1,3-dichlorobenzene Stowe 1,2,4-Trimethylbenzene Ethyl Acetate 1-Ethyl-4-Methylbenzene 1,3-Butadiene 4:1 Ethylbenzene 2:1 1,3,5-Trimethylbenzene 1,4-Dichlorobenzene Benzene 9 Seasonal Variations 10 High Temporal Resolution 24hr Average Hourly Concentration 11 Wind from Wind from Neville Island Downtown 14 12 benzene 10 toluene styrene g/m3) 8 μ 6 4 Conc. ( 2 0 1 3 9 10111718192122 October 2006 1.0 1.0 Styrene 0.8 Plume Events 0.8 0.6 Toluene 0.5 0.4 0.3 Benzene 0.2 0.0 0.0 12 Benzene by Day of the Week in Avalon Benzene 12 Benzene 10 g/m3) μ 8 6 4 Concentration (micrograms/m3) 2 Hourly Concentration ( 0 Sat Sun Mon Tues Wed Thurs Fri 13 Average Diurnal Patterns at Avalon 2.8 2.6 2.4 2.2 2 Concentration1.8 (microg/m3) 1.6 1.4 g/m3) μ 1.2 0.251 0 benzene 0.2 2:00 4:00 0.15 6:00 Concentration 8:00 (microg/m3)0.1 Concentrations ( 10:00 4 0.05 Military12:00 Time 3.5 14:00 cyclohexane 3 0 16:00 2.5 18:00 0 Concentration (microg/m3) 20:00 2:00 2 4:00 22:00 g/m3)1.5 6am 12 μ Time6:00 of day 8:00 1 1.8 10:00 0 Military Time toluene 12:00pm 6pm 1.6 2:00 14:00 4:00 1.4 16:00 6:00 18:00 Concentration 8:00 Concentrations(microg/m3)1.2 ( 20:00 10:00 22:00 Military12 Time:00 1 14:00 0.8 16:00 0 styrene 18:00 2:00 Time of day 20:00 4:00 22:00 6am 12pm 6:00 8:00 10:00 Military12 Time:00 14: 0 0 6pm 16:00 18:00 20:00 22:0014 Estimating Lifetime Cancer Risk Linear No-Threshold Model: Lifetime Individual Cancer Risk: LIR = LADD*SF SF=Slope Factor C95th, percentile * fa * IR Lifetime Averaged Daily Dose: LADD = BW 15 Air Toxics Cancer Risks Dichloropropane,1,2- Stowe Bromodichloromethane Risk=10-6 Downtown Methylene Chloride Avalon Hexachlorobutadiene Background Dichloroethane,1,2- Dichlorobenzene,1,4- Tetrachloroethene Chloroform Butadiene, 1,3- Trichloroethene Carbon Tetrachloride Benzene 0.E+000E00 5E-6 5.E-06 1.E-05 1E-5 2.E-051.5E-05 2.E-05 2E-5 Lifetime Cancer Risk 16 Non-Cancer Health Risks Concentration HQ = RfC HQ=Hazard Quotient RfC = Reference Concentration Q Chronic th T Annual 95 percentile canister data Q Intermediate and Acute T Maximum hourly concentration at Avalon: 14 days to 1 year 17 Non-Cancer Risks XYLENE, o- Stowe CARBON Downtown TETRACHLORIDE Avalon BROMOMETHANE Background CHLOROMETHANE TOLUENE XYLENE, m- BENZENE ACETONE HEXACHlOROBUTADIENE BUTADIENE, 1,3- HAZARD INDEX 0.00 0.20 0.40 0.60 0.80 1.00 Hazard Qoutient 18 Comparison of Aggregate Air Toxics Risks HAP Risk (Flag Plaza) HAP Risk (Avalon) Metals Risk (Background) HAP Risk (Stowe) HAP Risk (South Fayette) PAHs Risk (Background) 0.0E+00 5.0E-05 1.0E-04 1.5E-04 2.0E-04 Lifetime Cancer Risk 19 How does Allegheny County compare to other cities? 3.5 40 35 3 Avalon Stowe 30 2.5 Downtown g/m3) μ Background 25 2 20 Values Values 1.5 15 1 10 Concentration ( 5 0.5 0 0 1 2 1,3 Butadiene1 CCl2 4 Chlorform3 TCE4 Chloroethene5 Benzene Toluene Column Number Colu 20 1.E-03 8.E-04 percentile) (95th 6.E-04 Risk Cancer Lifetime 4.E-04 2.E-04 0.E+00 Annual Averaged 21 12/5/06 Year 11/5/06 Time Series 2006 10/5/06 50 Downtown40 Exposure: Trichloroethene 9/5/06 30 8/5/06 20 g/m3) μ 7/5/06 10 0 (95% (95% 6/5/06 1996 1998 2000 2002 2004 2006 2008 Concentration Concentration 5/5/06 1.0 4/5/06 0.8 3/5/06 0.6 g/m3) μ 0.4 2/5/06 0.2 1/5/06 0.0 Concentration ( Concentration Source Apportionment PMF solves: X = GF scores loadings Q Main issue: Associating sources and factors T Event profiles T Source profiles 22 Mobile Gasoline Factor 1 00 Styrene 330 330 3030 0.9 0.8 300300 6060 0.7 M/P 40 0.6 30 M/P Xylene 10 20 270270 90 Xylene 0.5 90 0.4 Toluene 240 120120 Toluene 0.3 240 0.2 210210 150150 0.1 Benzene 180180 0 Factor Contribution vs. Pittsburgh PMF Source Wind Direction Factor Profile 23 Water Treatment Factor 0 0 30 330330 30 300300 60 60 50 30 40 10 20 Tetrachloro 270270 90 90 ethylene 240240 120120 ACSA Toluene 210210 150150 180180 1 Factor Contribution vs. PMF ACSA Factor Emission Wind Direction Profile 24 Linking Risk to Sources 1,2,4_trimethylbenzene Cancer Risk o-xylene Exposure Styrene acetone Toluene Avalon Site 1,1,1_trichloroethane methylene chloride Benzene MEK toluene styrene benzene Neville Factor 0% 20% 40% 60% 80% 25 NATA Evaluation by Pollutant 2.0 2:1 8 1:1 g/m3) 2:1 g/m3) μ Styrene μ Toluene 1.5 6 1.0 1:1 CCl4 4 1:2 0.5 1:2 2 1-3 Butadiene Benzene Measured Concentration ( Concentration Measured 0.0 ( Concentration Measured 0 00.5102468 Modeled Conc.(μg/m3) Modeled Conc.(μg/m3) 26 NATA Evaluation by Site 3 25 2.5 20 2 15 1.5 10 1 Measured Modeled / 5 0.5 0 0 1,3-Butadiene Benzene Chloroform Toluene Styrene TCE 3 2.5 2 1. 5 1 Avalon Stowe Downtown Background 0.5 0 1, 3 - But adien e Benzene Chlor of or m Toluen e 27 NATA Evaluation: Source Apportionment Benzene 100% 75% Background 50% Mobile 25% Point 0% DowntownDowntown Avalon Avalon BackgroundBackground StoweStow e Avalon Avalon (NATA) (NATA) (NATA) (NATA) (PMF)(PMF) (NATA) 28 Application of Results Q Quantifying risk Q Source Apportionment Q Policy and funding decisions Q NATA evaluation 29 Lessons Learned Q Meeting all of our goals. Q Design of the project was sufficient to meet goals and additional scientifically interesting work is being done using the results. Q In retrospect 30 Future Work Q Intensives T Downtown T South Fayette Q Expand and improve PMF analysis Q Synergistic risk models Q NATA evaluation 31 Acknowledgments QFunding TClean Air Fund TEPA 32 Questions 33.
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