【摘要】 为评价抑芽丹在烟草上的消解趋势及安全性,建立了一种简单可行的残留量测定方法,并开展两年两地消解动态和最终残留研究。结果表明,烟草以酸化甲醇提取,SPE-C18固相萃取小柱净化,高效液相色谱测定,抑芽丹最低检测浓度为0.1 mg/kg。在1.0~80.0 mg/kg添加水平下,抑芽丹在鲜烟叶和干烟叶中的平均回收率分别为81.81%~95.89%和82.01%~83.08%,相对标准偏差分别为2.39%~7.03%和1.04%~1.71%。在消解动态试验施药后21 d,抑芽丹在烟草上的消解率超过90%,理论半衰期7.9~9.6 d,消解趋势符合一级动力学方程;施药后7 d,抑芽丹最终残留量低于80 mg/kg的指导性残留限量标准,安全风险处于较低水平。更多还原

【Abstract】 To evaluate the degradation trend and safety of maleic hydrazide in tobacco leaves, a simple and feasible residue analytical method was established, which was used in the study of digestion dynamics and final residues for 2 years. Maleic hydrazide in tobacco leaf samples was extracted with acid methanol and purified on C18 solid phase extraction column. The results showed that the limit of quantification(LOQ) was 0.1 mg/kg by the determination of high performance liquid chromatography. At spiked levels of 1.0-80.0 mg/kg, the average recoveries ranged from 81.81% to 95.89% for green tobacco leaves and from 82.01% to 83.08% for dried tobacco leaves, with relative standard deviations(RSD) of 2.39%-7.03% and 1.04%-1.71%, respectively. The results of maleic hydrazide degradation dynamic tests showed that the digestion rate in green tobacco was over 90% after 21 days of treatment, with the theoretical half-life being 7.9-9.6 days and the digestion trend was in line with the first order kinetic equation. Maleic hydrazide residues after 7 days of spraying were below the MRL of 80 mg/kg. The residual amount of maleic hydrazide in tobacco was at a lower level of safety risk.更多还原