氟啶胺在菊花中的残留消解动态及其风险评估

目的]建立了菊花中氟啶胺的液相色谱-串联质谱(QuEChERS-UPLC-MS/MS)分析方法,并在安徽、浙江、江苏和广西4地进行了500 g/L氟啶胺悬浮剂在菊花上残留的田间试验,研究了氟啶胺在菊花中的消解动态和最终残留量,并对菊花中氟啶胺可能产生的膳食摄入风险进行了评估。方法]菊花样品经乙腈提取,以C18色谱柱分离待测物,采用ESI源,负离子模式和多反应监测模式(MRM)检测,外标法定量。结果]在0.001~1.0 mg/L质量浓度范围内氟啶胺线性关系良好,相关系数大于0.9936;在0.010、0.10、0.50 mg/kg 3个质量分数下,菊花中氟啶胺的回收率为81.4%~92.5%,相对标准偏差(RSD)为1.6%~6.4%,检出限(LOD)为0.011~0.040μg/kg,方法定量限(LOQ)为添加的最低质量分数0.010 mg/kg。田间试验结果表明:氟啶胺在菊花中消解符合一级反应动力学方程,半衰期为3.5~3.9 d,属易降解农药;使用500 g/L氟啶胺悬浮剂,施药剂量300~450 g a.i./hm2,分别施药2、3次,距末次施药后14 d,菊花鲜样的残留量低于同期干样的残留量。结论]膳食摄入风险评估结果表明:氟啶胺的风险概率为每人每日摄入总量的77%,表明在菊花生长期间按照推荐剂量使用氟啶胺对消费者的膳食健康风险较低,对消费者健康是安全的。

Residual Dynamics and Risk Assessment of Fluazinam in Chrysanthemums

Aims]This study aims to develop a rapid method for determination of fluazinam residues in chrysanthemums by QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry(QuEChERS-UPLC-MS/MS).Field trials were conducted to evaluate the dissipation and residue of fluazinam in chrysanthemums in Anhui Province,Zhejiang Province,Jiangsu Province and Guangxi Province.The dietary exposure and risk assessment were also evaluated.Methods]The samples were extracted with acetonitrile,separated on a C18 column and detected under negative polarity multiple reactions monitoring(MRM)mode.The matrix-matched external standard calibration curves were used for quantitative analysis.Results]The results showed that,the linearity of fluazinam was in the concentration range of 0.001-1.0 mg/L with correlation oefficients higher than 0.9936.The average recoveries of fluazinam in chrysanthemums samples at three spiked levels of 0.010,0.10,0.50 mg/kg were in the ranges of 81.4-92.5%,and RSD were in the ranges of 1.6-6.4%,respectively.The limits of detection(LOD)for chrysanthemums was in the ranges of 0.011-0.040μg/kg,and the limit of quantification(LOQ)of fluazinam was 0.010 mg/kg which was the lowest spiked concentration.The results demonstrated that dissipation of fluazinam in chrysanthemums was in accordance with the first order kinetic equation with half-lives from 3.5 to 3.9 d.Applied fluazinam with 300-450 g a.i./ha,2 and 3 times,after 14 d,the residue of fresh chrysanthemum sample was lower than that of dry sample at the same time.Conclusions]Dietary intake risk assessment results showed that after 7 d,the risk probability of fluazinam was 77% at recommended dosage,which was not hazardous to people.