Concentrations and Influencing Factors of Hexachlorocyclohexanes (HCHs) in the Peacock River of Xinjiang, Northwest China

Hexachlorocyclohexane (HCH) was one of the major organochlorine pesticides (OCPs) in the water and sediments of the Peacock River in Xinjiang, China. Analyzing the water and sediment samples by gas chromatography-electron capture detection (GC-ECD), it showed that all the HCH isomers (alpha-HCH, beta-HCH, gamma-HCH and delta-HCH) could be found in the sediment, and the range was from 0.13 ng/g to 6.58 ng/g. The ratios of alpha-HCH/gamma-HCH at all the sites (except Site 2 and Site 6), were below 1.5, and it appeared that the sediment environment changed recently (there was newly input of gamma-HCH) and the Bosten Lake was the most possible source. In the water, only beta-HCH could be detected, the range was from N.D. to 0.019 mug/L. Discuss the influencing factors of HCH solubility: it showed that the high salinity reduced the solubility of HCHs into the water, and the alkalescence increased the solubility.