Abstract
The primary emission source contributions to fine organic carbon (OC) and fine particulate matter (PM2.5) mass concentrations on a daily basis in Atlanta, GA, are quantified for a summer (July 3 to August 4, 2001) and a winter (January 2–31, 2002) month. Thirty-one organic compounds in PM2.5 were identified and quantified by gas chromatography/mass spectrometry. These organic tracers, along with elemental carbon, aluminum, and silicon, were used in a chemical mass balance (CMB) receptor model. CMB source apportionment results revealed that major contributors to identified fine OC concentrations include meat cooking (7–68%; average: 36%), gasoline exhaust (7–45%; average: 21%), and diesel exhaust (6– 41%; average: 20%) for the summer month, and wood combustion (0–77%; average: 50%); gasoline exhaust (14–69%; average: 33%), meat cooking (1–14%; average: 5%), and diesel exhaust (0–13%; average: 4%) for the winter month. Primary sources, as well as secondary ions, including sulfate, nitrate, and ammonium, accounted for 86 ± 13% and 112 ± 15% of the measured PM2.5 mass in summer and winter, respectively.