新烟碱类杀虫剂对家蚕的急性毒性与风险评价

Acute toxicity and risk assessment of neonicotinoid insecticides to the silkworm,Bombyx mori

采用浸叶法测定了6种新烟碱类杀虫剂与其他2类对照杀虫剂对家蚕的急性毒性,且根据风险商值法进行了风险评价。结果表明:测试的6种新烟碱类杀虫剂中啶虫脒和噻虫胺对家蚕急性毒性96 h-LC50为0.262、0.268 mg·L^(-1),属剧毒级,而噻虫啉、吡虫啉、呋虫胺和噻虫嗪对家蚕急性毒性96 h-LC50分别为0.582、1.68、2.60、2.16 mg·L^(-1),均属高毒级。对照药剂高效氯氟氰菊酯、毒死蜱和马拉硫磷对家蚕急性毒性96 h-LC50分别为0.00909、0.785、1072 mg·L^(-1),分别属于剧毒级、高毒级和低毒级。风险评价结果表明:除马拉硫磷对家蚕的风险可接受外,其余8种杀虫剂均为不可接受。因此,在害虫综合治理中,应谨慎使用新烟碱类杀虫剂,以避免对家蚕生产造成危害。

In order to provide a scientific basis for the rational use of neonicotinoid insecticides,the acute toxicity of six neonicotinoid insecticides and other 2 kinds of control insecticides to the silkworm(Bombyx mori)were determined by using leaf dipping method,and the risk assessment was also carried out according to the risk quotient method.Results exhibited that the 96 h-LC50 values of acetamiprid and clothianidin to B.mori were 0.262 and 0.268 mg·L^(-1),respectively,which belonged to extremely toxic grade.The 96 h-LC50 values of thiacloprid,imidacloprid,dinotefuran and thiamethoxam to the organisms were 0.582,1.68,2.60 and 2.16 mg·L^(-1),respectively,which belonged to highly toxic grade.The 96 h-LC50 values of lambda-cyhalothrin,chlorpyrifos and malathion to the silkworms were 0.00909,0.785 and 1072 mg·L^(-1),respectively,which belonged to extremely toxic grade,highly toxic grade and lowly toxic grade,respectively.Risk assessment results indicated that the risk of malathion to the silkworm was acceptable,and the other eight insecticides were unacceptable.Therefore,neonicotinoid insecticides should be used cautiously in integrated pest management to avoid harm for sericulture.