Toxicological profile of pollutants in surface water from an area in TaihuLake, Yangtze Delta

The environment in Urbanized areas is often contaminated with a complex mix ture of toxic compounds originating from industries, agriculture and privat e households. Most of the contaminants end up in surface waters, such as la kes, rivers and finally the sea. Toxic contaminants may disturb the biologi cal condition of aquatic ecosystems and be harmful For humans, if they are transported to human food or drinking water. A variety of biological tests have been introduced for monitoring the toxicological profile of aquatic ec osystems. In the present investigation, genotoxic, hormone disrupting and A li-receptor activity was analyzed in water collected in January 1999 at Mei liang Bay, Taihu Lake, China. near to the city Of Wuxi in the Shanghai area . Significant mutagenic activity could be detected in water extracts with t he Salmonella/microsome assay and the arabinose resistance test. Frame shif t mutations were the predominant mode of action. Ah-reccptor active compoun ds were detected by using a luciferase reporter gene assay (CALUX-assay). T he estimated toxic equivalent factor-values ranged between 134 and 232 pg T CCD-equivalents per liter lake water. The estrogen-like potential of Taihu water was estimated with two luciferase reporter gene assays using transgen ic human cell lines expressing estrogen receptor alpha. Estradiol equivalen ts obtained with water extracts were in the range of 2.2-12.1 ng/l. We also analyzed the concentrations of 17-beta -estradiol and ethinylestradiol in the extracts using a high-pressure liquid chromatography-method. The values obtained correlated with the biologically determined estradiol equivalents , indicating that the estrogenic activity is mainly due to natural and synt hetic hormones rather than xenoestrogens. (C) 2001 Published by Elsevier Sc ience Ireland Ltd.