不同剂型高效氯氟氰菊酯对大型溞的毒性效应

为明确剂型对农药制剂毒性的影响,参照《化学农药环境安全评价试验准则》的方法,测定了高效氯氟氰菊酯乳油、脲醛树脂微胶囊悬浮剂、聚脲微胶囊悬浮剂和水乳剂3种剂型4种制剂对大型溞的急性毒性,并对其体长、摄食等亚急性毒性指标进行了比较.结果表明,加工成不同剂型均会提高药剂的毒性,高效氯氟氰菊酯原药对大型溞的48 h-EC50为2.50×10-3mg·L-1,乳油、脲醛树脂微胶囊悬浮剂、聚脲微胶囊悬浮剂和水乳剂3种剂型的4种制剂的48 h-EC50分别为8.04×10-4、6.25×10-4、1.56×10-3、1.65×10-3mg·L-1,且毒性随暴露时间延长而明显增加.亚急性毒性试验结果显示,当浓度为1.00×10-4mg·L-1时,3种剂型的4种制剂均会对体长、摄食等亚急性指标产生影响,且不同剂型的高效氯氟氰菊酯对大型溞体长的影响强弱顺序为:脲醛树脂微胶囊悬浮剂乳油聚脲微胶囊悬浮剂水乳剂,对摄食的影响为:乳油脲醛树脂微胶囊悬浮剂聚脲微胶囊悬浮剂水乳剂.

The toxicity effect of different formulations of lambda-cyhalothrin against Daphnia magna

The acute and sub-acute toxicity indicators such as body length and feeding to Daphnia magna were determined with different formulations of lambda-cyhalothrin, such as EC (emulsifiable concentrates), UFCS (urea-formaldehyde resin microcapsules), PUCS (polyurea microcapsules) and EW (emulsion in water), according to the Chemical Pesticides Environmental Safety Evaluation Test Guidelines. The results showed that the toxicities of different formulations were all higher than those of TC (technical material). The 48 h-EC₅₀ of lambda-cyhalothrin TC to Daphnia magna was 2.50×10^-3 mg·L^-1,while the 48 h-EC₅₀s of EC, UFCS, PUCS and EW were 8.04×10^-4, 6.25×10^-4, 1.56×10^-3, and 1.65×10^-3 mg·L^-1, respectively. In the sub-acute toxicity tests, the indicators of Daphnia magna such as body length and feeding were affected significantly at the concentration of 1.00×10^-4 mg·L^-1 for all the formulations. The inhibition effect of the four formulations of lambda-cyhalothrin on body length to Daphnia magna was UFCS>EC>PUCS>EW, and on the feeding was EC > UFCS >PUCS > EW.