不同剂型硝磺草酮及其原药对斑马鱼的急性毒性评价

【目的】评价不同剂型硝磺草酮及其原药对斑马鱼的急性毒性作用,为硝磺草酮的环境生态风险评估提供基础数据,同时为其安全用药提供参考依据。【方法】采用静态法测定不同剂型硝磺草酮及其原药对斑马鱼的急性毒性作用,并参照化学农药环境安全评价试验准则(GB/T 31270.12-2014),对各供试药剂对斑马鱼96 h的半致死浓度(96 h-LC_(50))的毒性等级进行划分。【结果】相同染毒时间下,不同剂型硝磺草酮及其原药对斑马鱼的LC_(50)不同。其中,10%硝磺草酮悬浮剂对斑马鱼的96 h-LC_(50)(95%置信限)最低,为6.70(5.18~8.15)mg a.i./L;其次为10%硝磺草酮可分散油悬浮剂和75%硝磺草酮悬水分散粒剂,对斑马鱼的96 h-LC_(50)(95%置信限)分别为10.89(9.29~12.43)和38.97(30.83~47.51)mg a.i./L;98%硝磺草酮原药对斑马鱼的96 h-LC_(50)最高,大于1.00×10~2mg a.i./L。依据化学农药环境安全评价试验准则(GB/T 31270.12-2014)进行判定,10%硝磺草酮悬浮剂对斑马鱼的急性毒性为中毒,其他3种为低毒,毒性排序为:10%硝磺草酮悬浮剂10%硝磺草酮可分散油悬浮剂75%硝磺草酮水分散粒剂98%硝磺草酮原药。【结论】不同剂型硝磺草酮及原药对斑马鱼的急性毒性存在明显差异,其毒性排序为:悬浮剂可分散悬浮剂水分散粒剂原药。因此,田间生产时应合理选择农药产品的剂型,并严格控制施药剂量,尽可能减少药剂进入水域环境对鱼类等水体生物造成影响。

Acute toxicity of mesotrione in different formulation and technical materials to zebrafish

Objective]The aim of the present study was to evaluate the acute toxicity of mesotrione in different for-mulations and technical materials to zebrafish,provide basic data for environmental ecological risk assessment for mesot-rione. At the same time,it could provide reference for rational use of this pesticide.Method]Acute toxicity of mesotrione in different formulations and technical materials to zebrafish was evaluated using static test. Toxicity levels of median lethal concentrationto zebrafish in 96 h(96 h-LC50)for the tested pesticides were divided based on Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticides(GB/T 31270.12-2014).Result]Under the same exposure time,LC50 of mesotrione in different formulations and technical materials to zebrafish was different. 96 h-LC50(95%confi-dence limit)of 10%mesotrione oil dispersion(OD)was the lowest6.70(5.18~8.15)mg a.i./L],followed by 10%mesot-rione suspension concentrate(SC),and 75%mesotrione water dispersible granule(WDG)which were 10.89(9.29-12.43) and 38.97(30.83-47.51)mg a.i./L respectively. 96 h-LC50 of 98%mesotrione technical material(TM)to zebrafish was the largest,more than 1.00 × 102 mg a. i./L. According to the Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticides(GB/T 31270.12-2014),the toxicity of 10% mesotrione SC to zebrafish was moderate,while the others were low. The rank of toxicity was:10% mesotrione SC>10% mesotrione OD>75% mesotrione WDG>98%mesotrione TM.Conclusion]Acute toxicity of mesotrione in different formulations and technical materials to zebrafish is different,the rank is as follows:mesotrione SC>mesotrione OD>mesotrione WDG>mesotrione TM. Therefore,in field cultivation,the formulations of pesticide should be selected accordingly,and the application dosage should be controlled to reduce the negative influence on fish caused by pesticides entering water area environment.