中文摘要：

对辽河和太湖流域表层沉积物中8种常见的拟除虫菊酯：联苯菊酯、高效氯氟氰菊酯、氯菊酯、甲氰菊酯、氟氯氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯进行分析测定.结果显示,太湖流域中拟除虫菊酯含量范围为0.02～2.91ng·g^-1（干重,下同）,平均含量为0.63ng.g^-1,处于相对较低的水平;辽河流域中的含量相对较高,其范围是0.14～19.6ng·g^-1,平均含量为6.20ng·g^-1.采用毒性单元TU（选用钩虾Hyallela Azteca的LC50）对拟除虫菊酯毒性风险进行估算,太湖流域∑TU值范围是0～0.40,相比之下,辽河流域的∑TU值高出很多,范围在0.10～1.73之间,其中有3个点位的∑TU值大于1,表明其具有一定的生态风险,其毒性主要来源于氯氰菊酯和氰戊菊酯.

英文摘要：

Eight widely used pyrethroids,including bifenthrin,lambda-cyhalothrin,permethtin,fenpropathrin,cyfluthrin,esfenvalerate,cypermethrin and deltamethrin,were analyzed in the sediments collected from Taihu Lake and Liaohe River.The total concentration of the 8 pyrethroids in Taihu Lake was relatively low,ranging from 0.02~2.91 ng · g^-1（dry weight,the same in the follows） with a mean value of 0.63 ng · g^-1.In comparison,the concentration in Liaohe River was relatively high and it varied in the range of 0.14～19.6 ng · g^-1 with an average of 6.20 ng · g^-1.Toxic units based on the LC50 of Hyallela Azteca were calculated to estimate the toxicity risk.The ∑TU was in the range of 0-0.40 for the sediments in Taihu Lake,while it was much higher in Liaohe River with a range of 0.10-1.73.The ∑TU was larger than 1 for three sediments in Liaohe River,suggesting pyrethroids in these sediments could present potential toxicity to benthonic organisms.The toxicity was mainly induced by deltamethrin and cypermethrin.