马铃薯中噻虫胺和嘧菌酯的残留和膳食风险评估

Determination and Dietary Risk of Clothianidin and Azoxystrobin Residues in Potatoes

该文建立了噻虫胺和嘧菌酯在马铃薯中残留的分析方法,马铃薯样品经乙腈-水混合溶液提取,无水硫酸镁MgSO_(4)和PSA净化后,上清液过0.22μm滤膜后,采用高效液相色谱-串联质谱检测。噻虫胺和嘧菌酯在0.005~0.5 mg/L范围内呈良好的线性关系,R2≥0.9972。在不同添加水平下,噻虫胺和嘧菌酯在马铃薯中的平均回收率在91.47%~98.13%之间,相对标准偏差(RSD)小于7.63%,定量限(LOQs)均为0.01 mg/kg。按照《农作物中农药残留试验准则》在全国12个地区开展规范残留试验,2%噻虫胺·嘧菌酯颗粒剂于马铃薯播种或移栽前以施药剂量900 g a.i./ha施用1次,施药方式为沟施。于收获期采集的马铃薯样本中,噻虫胺的残留量≤0.17 mg/kg,嘧菌酯的残留量≤0.074 mg/kg。根据毒理学数据、膳食结构和田间残留试验结果进行了长期膳食风险评估,结果表明:普通人群噻虫胺和嘧菌酯国家估算每日摄入量(NEDI)分别为0.2718 mg和2.6251 mg,膳食风险商(RQ)分别为4.31%和20.83%,均小于100%。说明在推荐的良好农业规范(GAP)条件下在马铃薯田施用2%噻虫胺·嘧菌酯颗粒剂不会对人体健康产生不可接受的风险。

A method for the simultaneous determination of clothianidin and azoxystrobin residues in potatoes was established.Samples were extracted with water and acetonitrile and then cleaned using anhydrous magnesium sulfate and primary secondary amine.The supernatants were filtered through 0.22μm filters,and the filtrate solutions were subjected to high-performance liquid chromatography-tandem mass spectrometry.Linear regression showed that extraction curves for both clothianidin and azoxystrobin were reasonably close to the standard curves within a concentration range from 0.005 to 0.5 mg/L,with a correlation coefficient higher than 0.9972.Average recovery rate of clothianidin and azoxystrobin from potatoes spiked with different pesticide levels ranging from 91.47%to 98.13%,with relative standard deviations less than 7.63%.The limit of quantification was 0.01 mg/kg for both analytes.Supervised residue trials were carried out in 12 areas in China according to the Ministry of Agriculture Guidelines for Testing of Pesticide Residues in Crops.Granules of 2%clothianidin+azoxystrobin were applied to the furrows beside the planting spots at the recommended dosage of 900 g a.i./ha before sowing or transplanting of potatoes.Clothianidin and azoxystrobin residues in potato samples at harvest were below 0.17 mg/kg and 0.074 mg/kg,respectively.Subsequently,dietary risk assessments were carried out based on the results of field residue trials,national dietary patterns,and toxicological data.The national estimated daily intakes of clothianidin and azoxystrobin were found to be 0.2718 mg and 2.6251 mg,respectively.The dietary risk quotients of clothianidin and azoxystrobin in potatoes were calculated as 4.31%and 20.83%,respectively,both less than 100%.This indicates that the application of granules of 2%clothianidin+azoxystrobin under the recommended Good Agricultural Practice conditions would not pose an unacceptable risk to human health.