Fang Ling, Long Nan, Li Ying, Liao Xiaofang, Shi Linchun, Zhao Haiping, Zhou Lidong, Kong Weijun
Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, China.
Pharmacy College, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China.
Ecotoxicol Environ Saf. 2022 Apr 1;234:113377. doi: 10.1016/j.ecoenv.2022.113377. Epub 2022 Mar 7.
Affected by some external conditions and internal factors, pesticides can be transferred from tea into its infusion, causing subsequent damage to humans as tea infusion is generally consumed. This study aimed to explore the inherent regularity in transfer behavior of 23 pesticides belonging to different classes from honeysuckle to its tea infusion, and to understand the effects of external brewing conditions and internal physicochemical parameters of the pesticides on their transfer rates. Results indicated that the transfer rates (Rt) of pesticides from honeysuckle into tea solutions increased with prolonged brewing time, or adding a cover on a container, but decreased with increasing the times of infusion. In addition, the transfer potential of these pesticides greatly depended on their physicochemical properties but not their type. The pesticides with high water solubility and low water partition coefficient (LogKow, e.g., omethoate) were more easily transferred into tea infusions than those with low water solubility and high LogKow (e.g., chlorpyrifos). Compared the tea brewing in a covered container, the empirical models obtained in an uncovered cup predicted the transfer behavior and drinking risk of pesticides potentially introduced into honeysuckle and its tea infusion. The linear equation was as follow: Rt = 10.756 LogWS + 7.517, R = 0.8771. In practice, honeysuckle should be brewed in an uncovered cup within a short brewing time, and the first tea infusion should be abandoned to reduce the transfer percentage of pesticides. This study provided beneficial references for pesticide application in honeysuckle plantation to establish realistic maximum residue limits of multi-pesticides in honeysuckle tea and related products.
受一些外部条件和内部因素的影响，农药会从金银花转移到其泡出的茶中，由于人们通常会饮用泡出的茶，这会对人体造成后续损害。本研究旨在探究23种不同种类农药从金银花转移到其泡出茶中的内在规律，并了解外部冲泡条件和农药内部理化参数对其转移率的影响。结果表明，农药从金银花转移到茶溶液中的转移率（Rt）随冲泡时间延长、容器加盖而增加，但随冲泡次数增加而降低。此外，这些农药的转移潜力很大程度上取决于其理化性质而非种类。水溶性高且水分配系数低（LogKow，如氧乐果）的农药比水溶性低且LogKow高（如毒死蜱）的农药更容易转移到泡出的茶中。与在加盖容器中泡茶相比，在无盖杯中得到的经验模型预测了可能引入金银花及其泡出茶中的农药的转移行为和饮用风险。线性方程如下：Rt = 10.756 LogWS + 7.517，R = 0.8771。在实际操作中，金银花应在无盖杯中短时间冲泡，且首泡应弃去，以降低农药的转移比例。本研究为金银花种植中的农药施用提供了有益参考，有助于制定金银花茶及相关产品中多种农药切实可行的最大残留限量。
