SOURCE APPORTIONMENT OF AIRBORNE PARTICULATE MATTER USING ORGANIC-COMPOUNDS AS TRACERS

A chemical mass balance receptor model based on organic compounds has been developed that relates source contributions to airborne fine part icle mass concentrations. Source contributions to the concentrations o f specific organic compounds are revealed as well. The model is applie d to four air quality monitoring sites in southern California using at mospheric organic compound concentration data and source test data col lected specifically for the purpose of testing this model. The contrib utions of up to nine primary particle source types can be separately i dentified in ambient samples based on this method, and approximately 8 5% of the organic fine aerosol is assigned to primary sources on an an nual average basis. The model provides information on source contribut ions to fine mass concentrations, fine organic aerosol concentrations and individual organic compound concentrations. The largest primary so urce contributors to fine particle mass concentrations in Los Angeles are found to include diesel engine exhaust, paved road dust, gasoline- powered vehicle exhaust, plus emissions from food cooking and wood smo ke, with smaller contributions from tire dust, plant fragments, natura l gas combustion aerosol, and cigarette smoke. Once these primary aero sol source contributions are added to the secondary sulfates, nitrates and organics present, virtually all of the annual average fine partic le mass at Los Angeles area monitoring sites can be assigned to its so urce. Copyright (C) 1996 Elsevier Science Ltd.