VOLATILE ORGANIC-COMPOUNDS IN URBAN ATMOSPHERES - LONG-TERM MEASUREMENTS OF AMBIENT AIR CONCENTRATIONS IN DIFFERENTLY LOADED REGIONS OF LEIPZIG

For the comprehensive characterization of ambient air concentrations o f a broad spectrum of volatile organic compounds (VOCs) an analytical method is described, consisting of adsorptive enrichment, thermal deso rption without cryofocusing, and capillary gas chromatographic separat ion. The method was applied during two-week measuring campaigns in win ter and summer 1995, and in the winter of 1996. Long-term sampling was carried out at sampling points in residential areas in the suburbs an d near the city center of Leipzig. About 70 VOCs - mainly hydrocarbons from propene to hexadecane - were identified both by GC-MS and chroma tographic retention data and quantified after external calibration. Me an values of VOC concentrations obtained during the sampling periods a re reported and discussed with regard to the topographical location of the sampling points in the Leipzig area, seasonal variations, and pos sible emission sources.