Xu Feng, Xu Duo, Du Gongming, Guo Zhenyu, Zha Xinxin, Chen Liuyang
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, People's Republic of China.
Analysis Center, Residue Laboratory, Jiangsu Pesticide Research Institute, Nanjing, People's Republic of China.
J Sci Food Agric. 2022 Oct;102(13):5826-5836. doi: 10.1002/jsfa.11932. Epub 2022 Apr 28.
Recently, chlorfenapyr and diafenthiuron have been widely used to prevent and control diseases and pests in tea production. However, rare studies have investigated the dissipation patterns of chlorfenapyr, diafenthiuron and their metabolites simultaneously in tea matrices. Here, we established an analytical method to investigate the degradation patterns of five target compounds in tea shoots and made tea samples. Moreover, the dietary intake risk assessment of chlorfenapyr-diafenthiuron mixture among Chinese populations was evaluated based on the supervised field experiment.
The mean recoveries of the primary analytes at five spiking levels were between 95.6% and 112.6% in tea shoots and made tea, respectively, and the values of RSD (relative standard deviation) were lower than 9.7% for all the target analytes. The field trial results showed that the half-lives of chlorfenapyr and diafenthiuron based on the residue definition were 10.0-12.4 days and 4.3-5.9 days, respectively, in tea shoots. For the dietary intake risk assessment, the risk quotient (RQ) values in made tea ranged from 30.4% to 73.9% at the pre-harvest interval of 14 days, which were significantly less than 100%.
The accuracy and precision of the developed method were satisfied by the measurement requirements according to the validation results. The dynamic dissipation experiments suggested that diafenthiuron was much easier to dissipate than chlorfenapyr. Moreover, the existence of tralopyril made the half-life of chlorfenapyr significantly increase, indicating that practical application of chlorfenapyr should take careful consideration of its metabolite. Finally, the potential chronic dietary risks of the chlorfenapyr-diafenthiuron mixture to human communities were within the acceptable range. © 2022 Society of Chemical Industry.
近年来，氯虫苯甲酰胺和丁醚脲在茶叶生产中被广泛用于病虫害防治。然而，鲜有研究同时考察氯虫苯甲酰胺、丁醚脲及其代谢物在茶叶基质中的消解规律。在此，我们建立了一种分析方法来研究茶树鲜叶和成品茶中5种目标化合物的降解规律。此外，基于田间监督试验，对中国人群中氯虫苯甲酰胺 - 丁醚脲混合物的膳食摄入风险进行了评估。
在茶树鲜叶和成品茶中，5个加标水平下主要分析物的平均回收率分别在95.6%至112.6%之间，所有目标分析物的相对标准偏差（RSD）值均低于9.7%。田间试验结果表明，基于残留定义，氯虫苯甲酰胺和丁醚脲在茶树鲜叶中的半衰期分别为10.0 - 12.4天和4.3 - 5.9天。对于膳食摄入风险评估，在收获前间隔14天的情况下，成品茶中的风险商（RQ）值在30.4%至73.9%之间，显著低于100%。
根据验证结果，所建立方法的准确度和精密度满足测定要求。动态消解实验表明，丁醚脲比氯虫苯甲酰胺更容易消解。此外，唑虫酰胺的存在使氯虫苯甲酰胺的半衰期显著增加，表明氯虫苯甲酰胺实际应用时应仔细考虑其代谢物。最后，氯虫苯甲酰胺 - 丁醚脲混合物对人类群体潜在的慢性膳食风险在可接受范围内。© 2022化学工业协会
