毛江胜　李慧冬　陈子雷　张文君　郭长英　方丽萍　丁蕊艳

摘要：建立了QuEChERS -液相色谱一质谱联用（LC - MS/MS）同时测定韭菜中噻虫胺和灭蝇胺残留量的分析方法，并采用该方法研究了这2种农药在韭菜中的消解动态及最终残留量。样品经乙腈提取，用N一丙基乙二胺（ PSA）、Cls和石墨化碳（PC）净化，正离子电离，多反应监测模式，LC-MS/MS测定，外标法定量。结果表明：在0. 005-1.000 mg/kg添加水平下，噻虫胺在韭菜中的平均回收率为90.0%～95.9%，相对标准偏差（RSD）为1.7%～3.3%;灭蝇胺在韭菜中的平均回收率为94.7～98.7%，RSD为0.8%～3.0%。样品中噻虫胺和灭蝇胺的定量限（ LOQ）分别为0.010、0.005 mg/kg。噻虫胺和灭蝇胺在韭菜中残留量均未检出。20%噻虫胺·灭蝇胺悬浮剂按有效成分l800g/h㎡施药2次，施药间隔期为45d，安全间隔期20d，噻虫胺在韭菜中的残留量均<0.01 mg/kg，灭蝇胺在韭菜中的残留量均<0.005mg/kg。

关键词：噻虫胺;灭蝇胺;韭菜;残留;消解;膳食风险评估

Dissipation Dynamics and Preliminary Dietary RiskAssessment of Clothianidin and Cyromazine in Chinese ChivesMao Jiangsheng， Li Huidong， Chen Zilei，Zhang Wenjun， Guo Changying， Fang Liping， Ding Ruiyan

Abstract In this study， a simple and practical QuEChERS - based liquid chromatography - tandemmass spectrometry （ LC - MS/MS） method was established to measure the residues of clothianidin and cyroma-zine in Chinese chives. The samples were extracted by acetonitrile and cleaned by primary secondary amine（ PSA） ， C18 and pesticarb （ PC） sorbent， and then were measured by LC - MS/MS operated in the positiveelectrospray ionization （ ESI） mode. The data were collected in multiple reaction monitoring （ MRM） mode.The results showed the average recoveries of clothianidin in Chinese chives were 90.0%～95.9% at the fourspiking levels from 0.005 to 1.0 mg/kg with the relative standard deviations （ RSDs） of l.7%～3.3% . Theaverage recoveries of cyromazine were 94.7～98.7% with the RSDs of 0.8%～3.0% . The limits of quantita-tion （ LOQs） of clothianidin and cyromazine were 0.01 mg/kg and 0.005 mg/kg， respectively. The dissipationdynamic studv showed that clothianidin and cyromazine in Chinese chives were not detected out. When 20%clothianidin - cyromazine SC was applied for 2 times at an interval of 45 days with the dose of 1800 g/h㎡ ，the residue of clothianidin was less than 0.01 mg/kg and that of cyromazine was below 0.005 mg/kg on the20th day after the last spray.

Keywords Clothianidin;Cyromazine; Chinese chives;Residue; Dissipation; Dietarv risk assessment

噻蟲胺（clothianidin），化学名称：1-（2一氯-5-噻唑基甲基）-3 -甲基一2一硝基胍，是具有噻唑环的新烟碱类杀虫剂，主要用于水稻、蔬菜、果树及其他作物田防治蓟马、蚜虫、飞虱等半翅目、鞘翅目、双翅目和一些鳞翅目害虫。灭蝇胺（cyromazine），又名环丙氨嗪，化学名称为N-环丙基-1，3，5-三嗪一2，4，6三胺，属三嗪类昆虫生长调节剂，在动植物体内可通过脱烷基作用代谢为三聚氰胺。灭蝇胺已在许多国家获准登记作为衣药使用，在我国主要用于防治菜豆、黄瓜、韭菜等蔬菜上的美洲斑潜蝇和潜叶蝇[1，2]。噻虫胺和灭蝇胺被分别推荐用于防治韭菜韭蛆，但缺乏两者在韭菜中的最大残留限量（MRL）标准，不仅为韭菜质量安全的监管带来困难，也可能对人体健康存在潜在的风险。……