Source-Receptor Reconciliation of South Coast Air Basin Particulate Air Quality Data

摘要

Chemical element balance and chemical tracer techniques are used to identify the source types contributing to particulate air quality in the South Coast Air Basin. An inventory of fine particle trace metals emissions in that air basin is constructed for the year 1976. It is shown that over 80% of the fine lead emissions come from highway traffic, 81% of the nickel arises from fuel oil fly ash, and more than 90% of the iron and manganese comes from soil-like materials. Then, using these metals as tracers for their most prominent source types, the ambient aerosol burden at 10 air monitoring sites is subdivided into contributions from particular source types. It is found that most monitoring sites are exposed to aerosol containing about 20% highway vehicle exhaust, 1% to 2% fuel oil fly ash, 20% to 50% soil dust or road dust, with sulfates and nitrates each present at about 15% of total mass. Source assessments based on currently available trace metals air monitoring data can be constructed and used to improve the accuracy of particulate emission control strategies.