8%甲氨基阿维菌素苯甲酸盐可溶液剂对4种环境昆虫的急性毒性与初级风险评估

Acute toxicity and primary risk assessment of emamectin benzoate 8% soluble agen to four environmental insects

[目的]明确8%甲氨基阿维菌素苯甲酸盐可溶液剂对4种环境昆虫的毒性效应与风险性。[方法]采用农业行业标准方法分别进行了家蚕(浸叶法),意大利蜜蜂(饲喂法、点滴法),螟黄赤眼蜂(药膜法)和七星瓢虫(药膜法)的急性毒性测试,获取其预测暴露浓度,结合田间推荐用药量进行初级风险评估。[结果]8%甲氨基阿维菌素苯甲酸盐可溶液剂对家蚕的急性毒性96 h-LC_(50)为5.03×10^(-4)mg a.i./L,毒性为剧毒;对蜜蜂的急性经口或接触毒性48 h-LD_(50)分别为1.49×10^(-3)、2.22×10^(-3)μg a.i./蜂,毒性等级均为高毒;对螟黄赤眼蜂和七星瓢虫急性毒性的LR_(50)分别为0.194、2.11 g a.i./hm^(2),风险等级分别为高风险、中等风险。风险评估结果为最外围和次外围桑树风险商值RQ分别为7.88×10^(4)、4.83×10^(3);蜜蜂喷施场景风险商值RQsp为40.3;赤眼蜂农田内外危害商值HQ分别为15.5、0.428,七星瓢虫农田内外危害商值HQ分别为1.42、0.0394。[结论]8%甲氨基阿维菌素苯甲酸盐可溶液剂对家蚕、蜜蜂、农田内赤眼蜂的暴露风险不可接受,在田间使用时需注意对家蚕、蜜蜂和赤眼蜂的保护。

[Aims]This study aims to determine the toxic effects and risk of emamectin benzoate 8%soluble agent on four environmental insects.[Methods]The acute toxicity tests of Bombyx mori(leaf soaking method),Apis mellifera(feedingmethod,dripmethod),Trichogramma chilonis(drug filmmethod)and Coccinella septempunctata(drug filmmethod)were carried out by using the standard methods of agricultural industry.The predicted exposure concentration were obtained,and the primary risk assessment was carried out in combination with the recommended dosage in the field.[Results]The results showed that the 96 h-LC_(50) for acute toxicity(emamectin benzoate)on B.moriwas 5.03×10^(-4) mg a.i./L(highly toxic);the 48 h-LD_(50) for acute oral or contact toxicity on A.mellifera were 1.49×10^(-3),2.22×10^(-3)μg a.i./bee(all are high toxic)respectively;the LR50 for acute toxicity on T.chilonis and C.septempunctata were 0.194(high risk)and 2.11(medium risk)g a.i./ha respectively.The risk assessment results showed that the risk quotient of the outermost and sub outermost mulberry trees were 7.88×10^(4) and 4.83×10^(3) respectively;the risk quotient of bee spray application scenario was 40.3;the hazard quotient of T.chilonis inside and outside farmland were 15.5 and 0.428 respectively,and the hazard quotient of C.septempunctata inside and outside farmland were 1.42 and 0.0394 respectively.[Conclusions]The exposure risk of emamectin benzoate 8%soluble agent to B.mori,A.mellifera and T.chilonis(inside farmland)were unacceptable.When used in the field,attention should be paid to the protection of B.mori,A.mellifera and T.chilonis.