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Urban Air Toxics
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The UAT Monitoring Network Urban Sites Asheville Charlotte Winston-Salem Raleigh Research Triangle Park Wilmington Rural Site Candor
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Monitoring Sites
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Site History
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Monitoring Site Information The Following Sites are Operated by: The Asheville Site: The Western NC Regional Air Quality Agency The Charlotte Site: The Mecklenburg County, Land Use and Environmental Services Agency The Winston-Salem Site: The Forsyth County Environmental Affairs Department
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Asheville Site
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Charlotte Garinger Site
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Winston-Salem Hattie Avenue Site
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Research Triangle Park
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Raleigh Millbrook Site
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Wilmington Battleship Site
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Candor Site
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Monitoring Methods
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EPA Toxic Organic (TO) Methods Volatile Organic Compounds (VOCs) EPA Method TO-15 (69 Analytes) Sample collected into pressurized SUMMA canister GC/MS with cryogenic preconcentration Carbonyls (aldehydes/ketones) EPA Method TO-11a (12 Analytes) Sample collected on a DNPH coated silica cartridge HPLC/UV of DNPH Derivatives Semi Volatile Organic Compounds (SVOCs) EPA Method TO-13a (33 Analytes) Sample collected on a polyurethane foam cartridge GC/MS of concentrated extract DNPH = Dinitrophenylhydrozene
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Limits of Detection VOCs TO-15 Lower Quantitation Level = 0.2 ppb Method Detection Level = 0.1 ppb Carbonyls TO-11a Method Detection Levels: Formaldehyde/Acetaldehyde = 10 ppt Other aldehyde/ketones = 5 ppt SVOCs TO-13a Lower Quantitation Level = 10 pg/m 3 Method Detection Level = 20 pg/m 3
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Hydrocarbons Hydrocarbons are derived mostly from petroleum sources and are the major components of fossil fuels, and petroleum products as well as plastics, waxes and oils. In urban environments, hydrocarbons (along with nitrogen oxides (NOx) and sunlight) contribute to ozone production. Benzene 1,3-Butadiene Toluene Ethylbenzene Styrene Xylenes
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Halogenated VOCs Volatile organic compounds that contain halogens such as chlorine, bromine, fluorine. Industrial solvent. Persistent in the atmosphere. Resist photochemical breakdown. Chronic health effects. Contribute to ozone formation. Carbon Tetrachloride Tetrachloroethylene Vinyl Chloride Freons
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Polar Compounds Polar compounds are oxygenated compounds such as ethers, ketones, and alcohols. Many of these compounds are used as gasoline additives so that emissions may be characteristic of those from mobile sources. MTBE MIBK MEK Ethanol
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Carbonyl Compounds Organic compounds composed of carbon, hydrogen, and oxygen and at least one carbon- oxygen double bond. Factors that effect may airborne concentrations: 1.Combustion sources, motor vehicles, industrial processes and some natural sources that emit compounds directly into the air. 2.Photochemical reactions that form carbonyl compounds in the air, typically from airborne hydrocarbons. 3.Photochemical reactions that consume carbonyls from the air, generally by photolysis or by reaction with hydroxyl radicals. FormaldehydeAcetaldehyde
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Semivolatiles (SVOC) Semivolatile: A substance that evaporates slowly at standard temperature and pressure (20°C & 1 atm). Polynuclear Aromatic Hydrocarbons (PAHs) Polychlorinated Biphenyls (PCBs) Polychlorinated Pesticides
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HAPs, TAPs, and Core Compounds HAP: Hazardous Air Pollutant (EPA) TAP: Toxic Air Pollutant (NCDAQ) Core Compound: A HAP or TAP that presents a high health risk due to long term exposure (i.e. 70 years) in an urban environment. Typically a carcinogen or chronic toxicant.
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Risk Assessment URE: The Unit Risk Estimate is the upper-bound excess lifetime cancer risk estimated to result from continuous exposure to an agent at a concentration of 1 µg/m3 in air. RfC: Reference Concentration (non-cancer) is an estimate of a concentration in air to which a human population might be exposed that is likely to be without appreciable risks of deleterious effects during a lifetime (assumed to be 70 years). Source: EPA
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UAT Monitoring Results
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UAT Core Compounds with detectable results Acetaldehyde Benzene 1,3-Butadiene Carbon Tetrachloride Formaldehyde Methylene Chloride Trichloroethylene
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UAT Core Compounds that were not detected Chloroform 1,3-Dichloropropene (cis & trans) Ethylene Dibromide Ethylene Dichloride Propylene Dichloride Tetrachloroethylene 1,1,2,2-Tetrachloroethane Vinyl Chloride
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HAPs and TAPs with detectable results Benzyl Chloride Carbon Disulfide Ethyl Acetate Ethylbenzene Freons 11, 12, & 113 Hexane Propionaldehyde Styrene Toluene Xylenes
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HAPs and TAPs that were not detected Bromoform Chlorobenzene p-Dichlorobenzene Ethlylidene Chloride Methyl Bromide Methyl Chloroform MIBK MTBE Vinylidene Chloride Vinyl Acetate Vinyl Trichloride
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Other Compounds of Interest with detectable results Acetone Benzaldehyde Butyraldehyde Cyclohexane Ethanol p-Ethyltoluene Heptane Isopropanol Methyl Ethyl Ketone
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Other Compounds of Interest that were not detected Crotonaldehyde Cyclohexane Dibromochloromethane Dichloroethenes (cis & trans) Dichlorobenzenes 2,5-Dimethylbenzaldehyde Freon 114 Hexaldehyde Isovaleraldehyde Methyl Butyl Ketone Valeraldehyde Tetrahydrofuran Tolualdehydes
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UAT Core Compounds: Average of All Years MDL
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Benzene: Raw Data
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Benzene: 3-Month Averages 15 Point Rolling Averages 0.0 0.2 0.4 0.6 0.8 1.0 7/1/0310/1/031/1/044/1/047/1/0410/1/041/1/054/1/057/1/0510/1/05 AshevilleGaringerWinston SalemRTPMillbrookWilmingtonCandor MDL URE
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Benzene: 2004 National Program
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Toluene: Raw Data 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 7/1/0310/1/031/1/044/1/047/1/0410/1/041/1/054/1/057/1/0510/1/05 AshevilleGaringerWinston SalemRTPMillbrookWilmingtonCandor
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Toluene: 3-Month Averages 15 Point Rolling Average 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 7/1/200310/1/20031/1/20044/1/20047/1/200410/1/20041/1/20054/1/20057/1/200510/1/2005 AshevilleGaringerWinston SalemRTPMillbrookWilmingtonCandor MDL
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Hexane: 3-Month Averages 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 7/1/0410/1/041/1/054/1/057/1/0510/1/05 AshevilleGaringerWinston SalemRTPMillbrookWilmingtonCandor MDL 15 Point Rolling Averages
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Freon 12: 3-Month Averages 15 Point Rolling Averages 0.0 0.2 0.4 0.6 0.8 1.0 1/1/20044/1/20047/1/200410/1/20041/1/20054/1/20057/1/200510/1/2005 AshevilleGaringerWinston-SalemRTPMillbrookWilmingtonCandor MDL
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Carbon Tetrachloride 3-Month Averages 0.0 0.1 0.2 0.3 0.4 1/1/044/1/047/1/0410/1/041/1/054/1/057/1/0510/1/05 AshevilleGaringerWinston SalemRTPMillbrookWilmingtonCandor 15 Point Rolling Averages MDL URE
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Carbon Tetrachloride: 2004 National Program
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Formaldehyde: Raw Data
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Formaldehyde: 2004 National Program Candor RTP
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Semivolatiles MDL
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Semivolatiles MDL
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VOC Annual Summaries: Asheville Percent Detect: Percent of total samples with detected values. nd: Not detected in any of the samples.
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VOC Annual Summaries: Charlotte Percent Detect: Percent of total samples with detected values. nd: Not detected in any of the samples.
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VOC Annual Summaries: Winston-Salem nd: Not detected in any of the samples Percent Detect: Percent of total samples with detected values.
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VOC Annual Summaries: Raleigh nd: Not detected in any of the samples Percent Detect: Percent of total samples with detected values.
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VOC Annual Summaries: RTP nd: Not detected in any of the samples Percent Detect: Percent of total samples with detected values.
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VOC Annual Summaries: Wilmington nd: Not detected in any of the samples Percent Detect: Percent of total samples with detected values.
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VOC Annual Summaries: Candor nd: Not detected in any of the samples Percent Detect: Percent of total samples with detected values.
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Carbonyl Annual Summaries: Candor/RTP
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