【摘要】 [目的]研究虱螨脲在韭菜和土壤中的残留和消解动态。[方法]样品中的虱螨脲用乙腈提取,采用QuEChERS法净化,通过高效液相色谱-串联质谱法测定虱螨脲的残留量。[结果]韭菜和土壤中虱螨脲的回收率为73.0%～89.5%,相对标准偏差为1.6%～10.4%。虱螨脲在韭菜和土壤中的半衰期分别为1.6 d和37.5～40.4 d,韭菜和土壤中的最终残留量分别为0.010～0.080 mg/kg和0.373～5.384 mg/kg,虱螨脲的风险商值为1.32×10-3,远低于1,为可接受风险。[结论]根据研究结果,建议我国虱螨脲在韭菜中的MRL值为0.1 mg/kg,且使用1%虱螨脲颗粒剂时的推荐施药剂量的高剂量22 500 g/hm2(225 g a.i./hm2),施药次数为1次,安全间隔期为7 d。更多还原

【Abstract】 [Aims] The aims were to study the residue and degradation dynamics of the Lufenuron in the leek and soil.[Methods] The lufenuron in leek and soil samples were extracted with acetonitrile, purified by Qu ECh ERS method, and determined by HPLC-MS/MS. [Results] The recoveries of lufenuron in leek and soil were 70.3-89.5% with the relative standard deviations of 1.6-10.4%. The half-lives of lufenuron were 1.6 d in leek and 37.5-40.4 d in soil. The final residues of lufenuron were 0.010-0.080 mg/kg in leek and 0.373-5.384 mg/kg in soil. The risk quotient for lufenuron was 1.32 ×10-3, far less than 1, which was acceptable risk. [Conclusions] According to the research results, it is suggested that the value of MRL for lufenuron in leek should be 0.1 mg/kg in China, and the recommended dosage is22 500 g/ha(225 g a.i./ha) that according the higher dose of the prescribed dose when is used the lufenuron 1%granules, application frequency is the one time and the safety interval is 7 d.更多还原