中国稻田登记噻虫嗪单剂的水生生态风险评估  

Aquatic Ecological Risk Assessment of Thiamethoxam Single Agent Registered in Rice Fields in China

作　　者：周蕾 程涵智 程再炜 郑豪杰 尹晓辉[1] Zhou Lei;Cheng Hanzhi;Cheng Zaiwei;Zheng Haojie;Yin Xiaohui(Modern Agricultural College,Zhejiang A&F University,Hangzhou 311300,China)

机构地区：[1]浙江农林大学现代农学院,杭州311300

出　　处：《生态毒理学报》2024年第4期259-269,共11页Asian Journal of Ecotoxicology

基　　金：国家自然科学基金项目(32372579,21007060);浙江省自然科学基金项目(LY14B070014);国家级大学生创新训练计划(202310341006);浙江省大学生科技活动计划暨新苗人才计划资助项目(2023R412034)。

摘　　要：为评估第二代新烟碱类杀虫剂噻虫嗪对水生环境的潜在风险,本文采用TOP-RICE模型,选取高浓度、短时间间隔和低浓度、长时间间隔2种施药方法,对我国在水稻上已登记的有效的施用方式为“喷雾”的噻虫嗪单剂品种进行暴露浓度预测。运用风险商值法对噻虫嗪进行水生生态风险评估。结果显示,截至2023年10月,近3年我国水稻上登记的有效噻虫嗪单剂共383种,主要剂型为水分散粒剂、可湿性粉剂、悬浮剂、种子处理悬浮剂、悬浮种衣剂、颗粒剂等,其中,水分散粒剂占比最大,占总量的28.72%。TOP-RICE模型预测结果显示,水分散粒剂、可湿性粉剂、悬浮剂3种噻虫嗪制剂产品在水稻上施用后,预测环境浓度范围为0.2300~29.2464μg·L^(-1),通过物种敏感性分布(SSD)曲线的绘制得到噻虫嗪对水生生物急性生态风险阈值(HC 5)为16.09μg·L^(-1),慢性HC 5为2.096μg·L^(-1),并且以溪流摇蚊为代表的大部分无脊椎动物对该杀虫剂较为敏感。结合风险商值(RQ)值的计算得出这3种剂型噻虫嗪对水生生态环境存在一定的威胁,在目前登记施用条件下,噻虫嗪可湿性粉剂的预测环境浓度较大,对水生生态系统的风险大于其他剂型。本研究由于通过模型完成,并且代谢物数据并不足,实验数据偏保守,结果存在一定的不确定性。To assess the potential risks of the second-generation neonicotinoid insecticide thiamethoxam to aquatic environments,this study utilized the TOP-RICE model to predict exposure concentrations for two application m ethods on rice,namely high concentration/short interval and low concentration/long interval,among the various thiamethoxam formulations registered in China for rice,applied by spraying.Risk quotient(RQ)method was e mployed to evaluate the aquatic ecological risks of thiamethoxam.The results showed that as of October 2023,a total of 383 effective thiamethoxam formulations for single application on rice were registered in China over the past three years,mainly including water dispersible granules,wettable powders,suspensions,seed treatment suspensions,suspension seed coatings,and granules,among which water dispersible granules accounted for the largest proportion at 28.72%.The TOP-RICE model predicted environmental concentrations ranging from 0.2300 to 29.2464μg·L^(-1)for thiamethoxam formulations of water dispersible granules,wettable powders,and suspensions after application on rice.The species sensitivity distribution(SSD)curve showed that the acute HC 5 of thiamethoxam to aquatic organisms was 16.09μg·L^(-1),and the chronic HC 5 was 2.096μg·L^(-1),and most invertebrates represented by Chironomus dilutus were sensitive to the insecticide.Calculations based on RQ values indicated that three formulations of thiamethoxam pose a certain threat to the aquatic ecological environment.According to the current registered application conditions,the predicted environmental concentration of thiamethoxam wettable powder was relatively high,indicating greater risks to aquatic ecosystems compared to other formulation types.Due to reliance on modeling and limited availability of metabolite data,coupled with conservative experimental data,there is some degree of uncertainty in the results of this study.

关 键 词：噻虫嗪 水稻 风险评估 水生生态系统 

分 类 号：X171.5[环境科学与工程—环境科学]