中文摘要：

微山湖作为南水北调东线工程的重要缓冲枢纽,其内源水质对整个东线工程的影响至关重要。为了研究微山湖水体和沉积物中有机氯农药污染的潜在风险,从微山湖30个采样点采集湖区上覆水和表层沉积物样品,采用气相色谱法对其中的有机氯农药含量进行测定。结果表明：1微山湖水体中有机氯农药六六六（HCHs）和滴滴涕（DDTs）的含量分别为34.4~195.9 ng/L和34.9~168.5 ng/L,与国内外其他地区湖泊相比,污染水平偏高,但均未超出我国地表水环境质量标准;沉积物中HCHs和DDTs含量分别为4.52~7.50 ng/g和4.73~7.67 ng/g,总体而言,相对国外其他地区湖泊污染水平偏高,相对国内其他地区湖泊污染水平偏低;2微山湖水体有机氯农药的非致癌风险总体处于低水平,致癌风险仍然存在,但随着采样时间的推移,水体中有机氯农药的非致癌风险和致癌风险均呈现递减趋势;3微山湖沉积物中有机氯农药的非致癌风险指数与致癌风险指数均小于风险警戒值,但90%的采样点沉积物中DDE和全部采样点沉积物中DDT的残留量介于环境影响低值（Effects range-low,ERL）和环境影响中值（Effects range-median,ERM）之间,会对生物产生毒性作用。

英文摘要：

Organochlorine pesticides（ OCPs） account for an important part of the history of pesticide development and were widely used in the past. However,OCPs undergo food chain amplification and,because of their very low water solubility,they accumulate in sediment and are highly carcinogenic,teratogenic and mutagenic to animals and humans. They have been listed as priority pollutants or persistent organic pollutants in many countries. Weishan Lake is an important hub on the East Route of the South to North Water Diversion Project and protecting its waterquality is essential to the project. Previous studies have reported organochlorine pesticide residues in the water and sediment of Weishan Lake. To evaluate the potential risk,we investigated the extent of organochlorine pesticide residues in the lake＇s water and sediment. The health risk of the residues was then evaluated using the U. S. EPA risk assessment protocol. On July 12,2009（ wet season）,December 23,2009（ dry season）,October 3,2010（ wet season） and January 20,2011（ dry season）,water and the upper sediment in Weishan Lake was sampled at 30 sites selected by considering water depth,lake area and surface runoff. The organochlorine pesticide residues in water and sediment samples were determined using gas chromatography. The three primary conclusions follow：（ 1）The concentration ranges of hexachlorocyclohexane（ HCH） and dichlorodiphenyltrichloroethane（ DDT） in Weishan Lake water were 34. 4- 195. 9 ng / L and 34. 9- 168. 5 ng / L,relatively high compared to most lakes in China and other countries,but do not exceed the environmental quality standards for surface water in China. The concentration ranges of HCH and DDT in the upper sediment were 4. 52- 7. 50 ng / g and 4. 73- 7. 67 ng / g,higher than in most lakes outside of China,but relatively low compared to other Chinese lakes.（ 2） The overall risk associated with pesticide residues in Weishan Lake water is low and,while arisk for carcinogenesis still exists,the risks are decr