高效氯氟氰菊酯在稻田使用后对水生生物的安全性研究

Study on the Safety of lambda-Cyhalothrin to Aquatic Organisms as it was Used in Paddy Field

采用半静态法研究了乳油（EC）、微乳剂（ME）、水乳剂（EW）、可湿性粉剂（WP）、悬浮剂（SC）5种不同剂型的高效氯氟氰菊酯对主要水生生物的急性毒性、在“稻田．鱼塘”模拟生态系统中的归趋及对其中水生生物的影响，旨在为评价高效氯氟氰菊酯在稻田使用后对水生生物的安全性以及控制其对水生生物的危害风险提供科学依据。结果表明，高效氯氟氰菊酯对河虾和鱼均为高毒，尤其河虾对其更为敏感；但5种不同剂型的高效氯氟氰菊酯对同种水生生物的毒性存在不同程度的差异。高效氧氟氰菊酯在环境中消解速率较快。不同剂型的高效氯氟氰菊酯在稻田水、鱼塘水和稻田土壤中的消解半衰期分别为0．23～0．53d、0．38—0．63d、0．96—7．35d。施药12h后降雨20min的稻田水进入鱼塘，对鱼、蟹和河蚌安全，对河虾会造成严重影响；但所有剂型的高效氯氟氰菊酯在用药4d后再排入鱼塘对河虾均达到安全水平。

To assess the safety of lambda-cyhalothrin used in paddy field to aquatic organisms, the acute toxicity of five different formulations（ EC ,ME,EW,WP and SC） of lambda-cyhalothrin to main aquatic organisms were determined by semi-static state method. The fate and risk of lambda-cyhalothrin to the aquatic organisms in paddy field-pond mimic ecosystem were also studied. The results showed that/ambda-cyhalothrin is highly toxic to both fish and shrimp, especially to shrimp. The toxicity of five formulations of/ambda-cyhalothrin ＇to the same aquatic organisms were different . The lambdacyhalothrin was degraded quickly in the environment, the half lives of different formulations of lambdacyhalothrin in paddy field water, pond water, and paddy field soil ranged from 0.23 d to 0.53 d, 0.38 d to 0.63 d, and 0.96 d to 7.35 d, respectively. The water overflow from paddy field since raining after 12 h of the use of lambda-cyhalothrin was safe to fish, mussel and crab, but was seriously hazardous to shrimp. However, the water overflow was safe to all the aquatic organisms tested after 4 d of use of all formulations.