8种杀虫剂在蔬菜中的田间残留消解动态

目的]建立同时测定蔬菜中8种农药残留的Qu ECh ERS/液相色谱-串联质谱(LC-MS/MS)方法。方法]采用LC-MS/MS分析了烯啶虫胺、螺虫乙酯、氯虫苯酰胺、氟啶虫酰胺、茚虫威、乙基多杀菌素、氟啶虫胺腈、吡虫啉8种农药在4种蔬菜中的残留消解动态。结果]浓度在0.005~0.200 mg/kg时,8种农药的质量浓度与对应峰面积呈良好的线性关系,相关系数均大于0.99,该方法对8种农药的检出限在0.005~0.020 mg/kg。在0.005、0.020和0.200 mg/kg 3个添加水平下,烯啶虫胺、氟啶虫酰胺、氯虫苯甲酰胺、茚虫威、吡虫啉在4种蔬菜中的平均回收率为60.8%~108.5%,相对标准偏差为1.7%~13.5%,在0.02、0.06和0.20 mg/kg 3个添加水平下,螺虫乙酯、氟啶虫胺腈、乙基多杀菌素在4种蔬菜中的平均回收率为71.4%~108.1%,相对标准偏差为1.1%~6.2%,满足农药残留检测要求。在田间试验采用推荐剂量处理,吡虫啉在甘蓝、辣椒、黄瓜、茄子上的半衰期分别为1.4、8.4、2.5、6.7 d。结论]试验结果为我国制定蔬菜最大残留限量标准提供了理论依据。

Simultaneous Determination of Eight Pesticides Residues in Vegetable

Objective] The aim was to establish a LC-MS/MS method for simultaneous determination of eight pesticides residues in vegetable.Method] The residue dynamic of chlorantraniliprole,flonicamid,spirotetramat,nitenpyram,indoxacarb,sulfoxaflor,spinetoram,imidacloprid in four vegetables were analyzed by LC-MS/MS.Result] Linear relationships between peak area and mass concentration of 8 pesticides were obtained in the range of 0.005-0.200 mg/kg.When the spiked levels were 0.005,0.020 and 0.200 mg/kg,the average recoveries of(nitenpyram,flonicamid,chlorantraniliprole,indoxacarb,imidacloprid)ranged from 60.8％ to 108.5％,with RSD (n =5) ranged from 1.7％ to 13.5％.When the spiked levels were 0.02,0.06 and 0.20 mg/kg,the average recoveries of spirotetramat,sulfoxaflor,and spinetoram ranged from 71.4％ to 108.1％,with RSD (n =5) ranged from 1.1％ to 6.2％,which meets the impection requirement of pesticide residue analysis methods.When recommended dosage of pesticides were applied,the half-lives of imidacloprid in four vegetables were 1.4,8.4,2.5 and 6.7 d.Conclusion] The results provide theoretical basis for making the maximum residue limits for vegetables in China.