Concentrations, Sources and Ecological Risk of Organochlorine Pesticides in Urban Stream Sediments of Suzhou Industrial Park, China

The concentrations, potential sources, and ecological risk of fifteen organochlorine pesticides (OCPs) in urban stream sediments of a Chinese national demonstration eco-industrial park, the Suzhou Industrial Park (SIP), were investigated. n-ary sumation OCPs in the sediments were 1.0- 23 ng g(-1) (mean = 9.9 +/- 5.0 ng g(-1)). Generally, HCHs and DDTs were the predominant OCPs and contributed 81% of n-ary sumation OCPs. Influenced by the difference in hydrological conditions and OCP use history, levels of OCPs in the sediments of the central area of SIP were lower than those of the outer region. Based on the source analysis, HCHs in the sediments were primarily influenced by the historical usage of technical HCH, and DDTs in the sediments were largely influenced by decayed technical DDT and dicofol. Endosulfans and chlordanes in the sediments were largely influenced by weathered sources. Ecological risk analysis suggested OCPs in sediments of most sampling sites would lead to a moderate toxic effect on sediment-dwelling organisms.