烯草酮·氯氰菊酯和2-4D丁酯对中华摇蚊幼虫的急性毒性研究

[目的]评价农药对水生生物的毒理效应。[方法]采用静水法研究烯草酮、氯氰菊酯和2-4D丁酯对中华摇蚊（Chironomussinicus）幼虫的急性毒性效应。分别设定不同浓度梯度进行急性暴露试验，于48h时测定摇蚊幼虫组织匀浆超氧化物歧化酶（SOD）的活性。[结果]在氯氰菊酯和2-4D丁酯处理摇蚊幼虫12h后，不同浓度间的存活率无显著差异，在48h时随着农药浓度的增加，存活率下降。烯草酮、氯氰菊酯和2-4D丁酯对中华摇蚊幼虫48h的Lc。分别为1．842、0．150和1．999mg／L，氯氰菊酯对中华摇蚊幼虫的毒性最高，其次为烯草酮，2-4D丁酯毒性最低。烯草酮对中华摇蚊幼虫组织SOD含量有明显影响，表现出剂量-效应关系；2-4D丁酯对组织SOD含量有明显影响，但未表现出剂量-效应关系；而氯氰菊酯对组织SOD含量则无明显影响。[结论]该研究为水体污染监测和水环境中农药的残留提供理论依据。

Acute Toxicity of Clethodim,Cypermethrin and 2,4-D-butylate on the Larva of Chironomus sinicus.

[ Objective] An experiment was conducted to study acute toxicity of clethodim, cypermethrin and 2,4-U-butylate on the larva ot Chironornus sinicus. [ Method ] The experiment was designed to have different levels of pesticides concentration. Superoxide dismutase （SOD） activities in the homogenate of tissues of the larva were monitored after they were exposed to the substance for 48 h. [ Result] Results showed that concentration had non-significant effects on survival rates of Chironomus sinicus for 12 h acute toxicity of Cypermethrin and 2,4-D-bury- late. For each pesticide, the differences in survival rates of Chironomtts sinicus in 48 h were significant. The 48 h-LC50 of Clethodim, Cypermethrin and 2,4-D-butylate to Chironomus sinicus larvae were 1. 842, 0. 150 and 1. 999rag/L, respectively. The acute toxicity of Cypermethrin was the highest among the three kinds of pesticide but the acute toxicity of 2,4-D-butylate was the lowest. Clethodim displayed significant effects on the activities of SOD, and such effects were significantly related to dosage of the substance. 2,4-D-butylate displayed significant effects on the activities of SOD, but effects were non-significantly related to dosage of the substance. But Cypermethrin displayed non-signifi- cant effects on the activities of SOD. [ Conclusion] The study provided the basis for monitoring of water pollution and pesticide residues in water environment.