HR: 0800h
AN: A51D-0730    [Abstracts]
TI: Quantification of Wood Smoke Markers in Fine Atmospheric PM in the New York City Airshed
AU: * Hawley, H A
EM: hawley@eden.rutgers.edu
AU: Mazurek, M A
EM: mmazurek@rci.rutgers.edu
AU: Li, M
EM: liminlh@rci.rutgers.edu
AB: Seasonal emissions from residential wood combustion, natural wildfires, agricultural burning and solid waste combustion are considered to be major sources of fine particles to the NYC metropolitan airshed. Wood smoke produced from the combustion of cellulosic material consists of polar organic compounds which are highly water-soluble. As alternative forms of energy production including biofuels for residential heating are developed and become more widely used, a key science question is how much of the carbonaceous PM2.5 currently is from wood smoke in urbanized areas and to what extent is this influencing atmospheric chemical properties. This project focuses on the quantitation of polar organic compounds extracted from fine particle samples (PM2.5) collected as part of the Speciation of Organics for Apportionment of PM-2.5 in the New York City Area (SOAP). The SOAP network operated from May 2002 to May 2003 at four sites: Queens, NYC (high density urban residential); Elizabeth, NJ (adjacent to the NJ Turnpike); Westport, CT (downwind NYC residential); and a regional background site in Chester, NJ (upwind NYC). A quantitative extraction and gas chromatographic/mass spectrometric (GC/MS) chemical analysis procedure was developed and evaluated. Trimethylsilyl (TMS) derivatives were prepared prior to GC/MS analysis and 5-point calibrations and multiple replicates were evaluated to ensure method precision. Levoglucosan was used as the primary marker for cellulose combustion; however a suite of monosaccharides and disaccharides and dehydroabietic acid, a marker indicative of soft wood combustion, also were quantified. Levoglucosan was found during each season at all four sampling locations with ambient mass concentrations ranging from 2.36 ng/m3 to 189 ng/m3. These values represent an estimated low of 0.73 percent to a high of 69 percent of organic carbon in the fine PM from wood smoke. The lowest levoglucosan concentrations were present consistently at the Chester, NJ upwind site and the highest were seen most frequently in Westport, CT, a predominantly residential area. Levoglucosan concentrations were lowest in spring and highest during late fall, early winter, or late winter. The results from the remaining sugar marker compounds showed no persistent trends spatially or seasonally. Dehydroabietic acid also was found in the fine PM with similar trends to levoglucosan; the concentrations ranging from a low of 1.6 ng/m3 (Westport, spring) to a high of 98 ng/m3 (Elizabeth, early spring). These results for metropolitan NYC indicate that wood smoke is currently a major component of PM mass and is prevalent year round and is derived from a combination of seasonally variable sources.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting