3种常用水产杀虫剂对大型溞的急性毒性

Acute Toxicity of Three Conventional Insecticides in Aquaculture to Water Fleas Daphnia magna

在水温(23±1)℃下,研究辛硫磷、敌百虫和甲苯咪唑等3种常用水产杀虫剂对大型溞的急性毒性。结果表明,敌百虫对大型溞24h和48h的半致死质量浓度分别为70.13μg/L和22.96μg/L,安全质量浓度为0.74μg/L;辛硫磷对大型溞24h和48h的半致死质量浓度分别为0.93μg/L和0.24μg/L,安全质量浓度为0.0048μg/L;甲苯咪唑对大型溞24h和48h的半致死质量浓度分别为104.31μg/L和27.56μg/L,安全质量浓度为0.58μg/L。3种杀虫剂对大型溞的毒性:辛硫磷>敌百虫>甲苯咪唑,均属于剧毒,在水产养殖过程中应谨慎使用。

In this study, the acute toxicity of phoxim, trichlorfon and mebendazole to water fleas Dalhnia magna was studied at water temperature of （23±1） ℃. It was found that the median-lethal concentration （LC50） of trichlorfon was 70.13 μg/L in 24 h and 22.96μg/L in 48 h, with safe concentration of 0.74 μg/ L. The LC50 of phoxim was found to be 0.93 μg/L in 24 h and 0.24 μg/L in 48 h, with safe concentration of 0. 0048 μg/L. Mebendazole had LC50 of 104.31μg/L in 24 h and 27.56μg/L in 48 h, with safe concen tration of 0.58 μg/L. The order of acute toxicity to the water fleas was expressed as the phoxim〉trichlor- fon〉mebendazole. According to the standard evaluation procedure of compounds toxicity to aquatic organ isms, trichlorfon, phoxim and mebendazole are all highly toxic to the water fleas, indicating that they should be cautious to the potential risks in aquaculture.