82%嗪·异丙甲·滴辛酯乳油在大豆上残留的检测方法及膳食风险评估

Detection Methods of 82%Metolachlor·Metribuzin·2,4-D-Ethylhexyl EC on Soybean and Its Dietary Risk Assessment

为评价异丙甲草胺、嗪草酮和2,4-滴异辛酯的复配农药82%嗪·异丙甲·滴辛酯乳油在大豆生产上的安全性,本研究使用改进的QuEChERS前处理方法,并通过超高效液相色谱串联质谱和气相色谱对大豆、青豆、大豆秸秆和青豆秸秆中的异丙甲草胺、嗪草酮和2,4-滴异辛酯及其中间代谢物2,4-滴进行定量测定。并依据国家估算的每日摄入量与可接受的每日摄入量,评估这些农药的风险系数。结果表明:异丙甲草胺、嗪草酮、2,4-滴异辛酯及2,4-滴在不同样品中的平均回收率为72.3%~105.7%,相对标准偏差为0.9%~14.0%;4种除草剂成分在大豆和青豆中的最低检出浓度分别为0.02,0.005,0.005和0.005 mg·kg^-1,在大豆秸秆中的最低检出浓度均为0.04 mg·kg^-1,在青豆秸秆中的最低检出浓度均为0.02 mg·kg^-1。该方法可应用于测定大豆田间试验样品中异丙甲草胺、嗪草酮、2,4-滴异辛酯及2,4-滴的含量。良好农业规范条件下,大豆、青豆、大豆秸秆和青豆秸秆中的异丙甲草胺、嗪草酮、2,4-滴异辛酯和2,4-滴最终残留量均未检出。普通人群异丙甲草胺、嗪草酮和2,4-滴异辛酯的国家估计每日摄入量分别为0.08373,0.0116和0.2795 mg·(kg bw)^-1,风险系数分别为1.33%、1.41%和44.36%,这表明在良好农业规范条件下以2460 g a.i.hm^-2用量浓度施用3种除草剂复合的82%嗪·异丙甲·滴辛酯乳油对消费者的健康风险较低。

To evaluate the safety of compound pesticide 82%metolachlor·metribuzin·2,4-D-ethylhexyl EC of metolachlor,metribuzin and 2,4-D-ethylhexyl in soybean,this study used an improved QuEChERS pretreatment method coupled with Ultra Performance Liquid Chromatography Tandem Mass Spectrometry(UPLC-MS/MS)and Gas Chromatography(GC)to determine metolachlor,metribuzin,2,4-D-ethylhexyl and intermediate metabolite 2,4-D in soybean,immature soybean,soybean straw and immature soybean straw.The risk factors(Risk Quotients,RQ)of these pesticides were evaluated by comparing the national estimated daily intake with the acceptable daily intake.The results showed that the average recovery of metolachlor,metribuzin,2,4-D and 2,4-D-ethylhexyl in samples were 72.3%-105.7%,and the Relative Standard Deviation(RSD)was 0.9%-14.0%.The limit of quantitation(LOQ)of metolachlor,metribuzin,2,4-D and 2,4-D-ethylhexyl in soybean and immature soybean were repectively 0.02,0.005,0.005 and 0.005 mg·kg^-1,in soybean straw was 0.04 and in immature soybean straw was 0.02 mg·kg^-1.This method has been successfully applied to determine the concentration of metolachlor,metribuzin,2,4-D-ethylhexyl and 2,4-D in soybean field test samples.Under the conditions of Good Agricultural Practices(GAP),the terminal residues of metolachlor,metribuzin,2,4-D-ethylhexyl and 2,4-D in soybean,immature soybean,soybean straw and immature soybean straw were not detected.The National Estimated Daily Intake(NEDI)of metolachlor,metribuzin and 2,4-D for the general population was 0.08373,0.0116 and 0.2795 mg·(kg bw)^-1,respectively,and the RQs were 1.33%,1.41%and 44.36%,which showed that the application of 82%metolachlor·metribuzin·2,4-D-ethylhexyl EC compound of the three herbicides under GAP conditions had a lower health risk for consumers.