Xu Feng, Ren Wenhao, Fang Xinting, Chen Liuyang, Zha Xinxin
Analysis Center, Residue Laboratory, Jiangsu Evertest Co., Ltd., Nanjing, 210046, China.
Environ Sci Pollut Res Int. 2021 May;28(18):22641-22650. doi: 10.1007/s11356-020-12223-8. Epub 2021 Jan 9.
The residue detection method and field dissipation dynamics of the pymetrozine-clothianidin mixture in strawberries were investigated combining QuEChERS pretreatment and LC-MS/MS analysis to provide a reference for the safe use of pymetrozine and clothianidin mixture on strawberries. Good linearity (R > 0.999) was obtained for pymetrozine and clothianidin within the range of 0.005-1 μg mL. Method validations indicated that the recovery for pymetrozine and clothianidin was 84.2-101.4%, intra-day and inter-day repeatability ranged from 1.8 to 8.1% and from 4.1 to 7.0%, respectively. Following application of the recommended dose in field trials, pymetrozine and clothianidin dissipation followed first-order kinetics with half-lives of 6.8-13.9 days in strawberries at four locations. Moreover, owing to risk quotient < 100%, a mixture pesticide of 30% suspension concentrates (25% pymetrozine + 5% clothianidin) was unlikely to give rise to vital health concerns to humans following the recommended application guidelines. This study can be utilized in safety assessment and developing spray schedules for this mixed pesticide in strawberries.
结合QuEChERS预处理和LC-MS/MS分析，研究了草莓中吡蚜酮-噻虫胺混合物的残留检测方法及田间消解动态，为吡蚜酮和噻虫胺混合物在草莓上的安全使用提供参考。吡蚜酮和噻虫胺在0.005-1μg/mL范围内具有良好的线性关系（R>0.999）。方法验证表明，吡蚜酮和噻虫胺的回收率为84.2-101.4%，日内和日间重复性分别为1.8-8.1%和4.1-7.0%。在田间试验中施用推荐剂量后，吡蚜酮和噻虫胺在四个地点的草莓中的消解符合一级动力学，半衰期为6.8-13.9天。此外，由于风险商<100%，按照推荐的施用指南，30%悬浮剂（25%吡蚜酮+5%噻虫胺）的混合农药不太可能对人类健康造成重大影响。本研究可用于该混合农药在草莓中的安全性评估和制定喷雾时间表。
