萝卜中除虫脲的消解动态及慢性摄入风险评估

Dissipation Kinetics and Chronic Intake Risk Assessment of Diflubenzuron in Radish

[目的]建立一种萝卜及萝卜叶中除虫脲的检测方法,研究其消解及最终残留情况,并对其慢性摄入风险进行评估。[方法]样品用20 mL二氯甲烷-石油醚(体积比3∶4)提取,Cleanert SC_(18)-SPE柱净化,高效液相色谱法定性定量分析。[结果]除虫脲在萝卜中的平均回收率为89.72%～102.29%,相对标准偏差为3.57%～8.76%;在萝卜叶中的平均回收率为75.84%～99.96%,相对标准偏差为7.35%～11.40%;除虫脲在一定浓度范围内线性关系良好,R2>0.99;除虫脲在贵州和安徽萝卜叶中的消解半衰期分别为5.92、5.87 d;慢性摄入风险评估中,RQ值在0.048～0.130范围内,远低于1。[结论]该方法线性关系、准确度和精密度良好,能够有效地检测萝卜和萝卜叶中除虫脲的残留量。在推荐施药剂量和施药次数下,其慢性摄入对人类健康的风险可接受。

[Aims] A analysis method was established to determine the diflubenzuron in radish and radish leaf samples.Its dissipation and final residue were studied to evaluate the chronic dietary risk. [Methods] The sample was extracted with 20 mL of mixture of dichloromethane and petroleum ether with ratio of 3 ∶4（by vol）, purified by a Cleanert SC（18）-SPE column, and then qualitatively and quantitatively analyzed by HPLC. [Results] The average recovery of diflubenzuron in radish was 89.72-102.29% with relative standard deviations（RSD） of 3.57-8.76%, the average recovery in radish leaves was 75.84-99.96% with RSD of 7.35-11.40%. Diflubenzuron has a good linear relationship within a certain concentration range with correlation coefficients（R^2） 〉 0.99. The dissipation half-lives of diflubenzuron in Guizhou and Anhui radish leaves were 5.92 and 5.87 d, respectively. For the chronic dietary risk assessment, RQ value were in the range of 0.048 to 0.130, far below 1. [Conclusions] The method showed satisfactory linearity relationship, accuracy and precision. It can effectively determine the residues of diflubenzuron in radish and radish leaves. The chronic dietary risk is acceptable for human health at the recommended dose and frequency of application.