TOXIC VOLATILE ORGANIC-COMPOUNDS IN URBAN AIR IN ILLINOIS

Airborne concentrations and sources of 13 toxic volatile organic compounds (VOCs) were evaluated in two urban areas in Illinois: southeast Chicago and East St. Louis. Concentrations and meteorological conditions were monitored between May 1986 and April 1990. Using emissions inventories and source signatures developed for the study areas, we applied wind trajectory analysis, factor analysis, and a chemical mass balance model to interpret the data. These analyses indicate that most of the toxic VOCs in the study areas come from urban area sources such as vehicle exhaust, evaporation of petroleum products, and solvent emissions by commercial and industrial sources. Emissions from large industrial point sources increase VOC concentrations within 1 km from the source, but have little effect on the overall air quality in the study areas.