Determination of organic micropollutants in rain water for laboratory screening of air quality in urban environment

Rain water may collect organic air pollutants, such as polycyclic aromatic hydrocarbons (PAHs), phthalate ester (PEs), pesticides, and polychrorinated biphenyls (PCBs), that could be present in air in consequence of different factors. The determination of these compounds in rain water samples conseq uently may be interesting for a first screening of air quality in urban and /or industrial. areas. For this purpose, 3 areas of the city of Rieti (central Italy) were selecte d for rain water sampling: a) the city center, densely populated and with h igh road traffic; b) a suburban residential area; c) the industrial area, a bout 3 km out of the city center and along the state road. Wet-only precipi tation collectors were used for sampling; solid-phase microextraction or li quid-liquid microextraction techniques followed by GC/MS determinations wer e applied for sample analysis. PCBs and pesticides were never found in the samples collected. On the contr ary, some polycyclic aromatic hydrocarbons and phthalates were always found . Significant and seasonal differences in PAH levels were observed in the 3 different sampling areas, with higher values always found in the city cent er and during the winter period; on the contrary, PEs levels remained uncha nged. (C) 2000 Elsevier Science Ltd. All rights reserved.