贵州地区茶叶及茶汤中氯氰菊酯残留量检测及其摄入风险分析

Detection and risk assessment of cypermethrin residue in tea and tea infusion in Guizhou

采用气相色谱建立了茶叶样品中氯氰菊酯残留量检测方法;通过对贵州省市售茶叶样品中氯氰菊酯的残留情况进行抽检,以了解其市售茶叶的安全性;通过田间试验制备浸泡实验用茶叶样品,设计正交实验研究了影响茶汤中氯氰菊酯浸出率的因素。结果表明,市场抽检茶叶样品中氯氰菊酯残留量平均值为0.919 mg/kg,最高残留量为1.52 mg/kg,低于茶叶中氯氰菊酯的最大残留限量(MRL)标准20 mg/kg;正交实验表明,浸泡次数和浸泡时间是影响氯氰菊酯浸出率的主要因素,茶汤中氯氰菊酯的最高浸出率为5.76%。按人均最高泡茶用量13 g/d计算,由饮茶而进入人体的氯氰菊酯的最大量为1.5×10-2mg/d,按氯氰菊酯每日最大允许摄入量(ADI)为0.05 mg/kg bw、平均体重60 kg计,则其安全系数(K)为200。

Gas chromatography was used to determine the residue level of cypermethrin in tea samples.Determination of cypermethrin residues was investigated to evaluate the tea samples to be sold in Guizhou Province.An orthogonal field experiment was designed to study the factors that influence the extraction rate of cypermethrin.The results showed that the average and highest cypermethrin residue of the teas on Guizhou Province market was 0.919 mg/kg and 1.52 mg/kg which were much lower than the maximum residue limit（MRL） of 20 mg/kg for cypermethrin.The result of the orthogonal experiment showed that the times and time of soaking were the main factors affecting the extraction rate of cypermethrin.The highest extraction rate of cypermethrin was 5.76% for an average person,which suggested a maximum daily intake of 1.5×10-2 mg.The safety coefficient（K） was 200,acceptable daily intake（ADI） 0.05 mg/kg bw for cypermethrin,average weight 60 kg.