吡唑醚菌酯在小麦上的残留分析及安全性评价研究

Residue analysis and safety evaluation of pyraclostrobin on wheat

中文关键词:  吡唑醚菌酯  小麦  残留  消解  超高效液相色谱-串联质谱法

英文关键词:pyraclostrobin  wheat  residue  digestion  ultra performance liquid chromatography/tandem mass spectrometry

中文摘要:

      目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography/tandem mass spectrometry, UPLC-MS/MS)测定小麦中吡唑醚菌酯的含量, 研究其在小麦籽粒和秸秆中的残留状况及消解规律, 评估吡唑醚菌酯的膳食风险。方法 实验样品经乙腈提取、净化后, 经Waters Acquity UPLC BEH C18柱(50 mm×2.1 mm, 1.7 μm)分离, 以0.1%甲酸水-甲醇为流动相进行梯度洗脱; 流速为0.3 mL/min, 多反应监测模式监测。结果 吡唑醚菌酯在0.0005~0.20 mg/mL的范围内线性关系良好, 相关系数大于0.999, 小麦籽粒、小麦秸秆不同添加水平下的平均回收率范围为66%~97%、88%~98%, 相对标准偏差分别为1.9%~5.5%、1.2%~12.4%, 定量限为0.01 mg/kg。吡唑醚菌酯在小麦籽粒中的残留消解符合一级动力学方程, 其消解半衰期为2.74~5.82 d; 用药后小麦籽粒中吡唑醚菌酯的最终残留未检出~0.10 mg/kg; 膳食风险评估表明, 末次施药21 d后吡唑醚菌酯的国家估算每日摄入量是1.0874 mg, 风险概率为57.53%。结论 吡唑醚菌酯在小麦中的消解速度较快, 虽不能在小麦中完全降解, 但通过膳食评估发现长期膳食摄入对人体健康不会产生不可接受的风险。

英文摘要:

      Objective To establish an ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method for the determination of pyrazoxystrobin in wheat, study its residual status and digestion rule of pyrazoxystrobin in wheat grains and straw, and assess the dietary risk of pyraclostrobin. Methods After the experimental samples were extracted and purified by acetonitrile, and separated by Waters Acquity UPLC BEH C18 column(50 mm×2.1 mm, 1.7 μm) with 0.1% formic acid water-methanol gradient elution as the mobile phase at the flow rate of 0.3 mL/min, monitored by multiple- reaction monitoring mode. Results The pyrazoxystrobin had a good linear relationship in the range of 0.00050.20 mg/mL, with a correlation coefficient greater than 0.999. The average recovery rates of wheat grains and wheat straw under different levels of addition were 66%97%, 88%98%, and the relative standard deviations were 1.9%5.5%, 1.2%12.4%, respectively. The limit of quantitation was 0.01 mg/kg. The digestion state of pyraclostrobin in wheat grain accorded with the first-order degradation kinetics, and the half-life of digestion was 2.74~5.82 days. The final residue of pyraclostrobin in wheat grain after treatment was not detected0.10 mg/kg, The national estimated daily intake of pyraclostrobin after the last application of 21 d was 1.0874 mg, and the risk probability was 57.53%. Conclusion Pyraclostrobin has a faster digestion rate in wheat, although it cannot be completely degraded in wheat, dietary assessment has found that long-term dietary intake does not pose unacceptable risks to human health.