茶叶中高氯酸盐的污染情况及健康风险初步评估

Pollution and Health Risk Assessment of Perchlorate in Tea of China

采用高效液相色谱-串联质谱法测定我国中、东、西部地区15个省份279个茶样高氯酸盐含量,利用US EPA推荐的四步法对不同地区茶样高氯酸盐污染情况进行健康风险评估。结果显示:高氯酸盐整体检出率为98.6%,检出量从ND(<检出限/未检出)~1.6466 mg/kg,中位值为0.1138 mg/kg,检出的高氯酸盐超标率(≥0.75 mg/kg)为3.9%。各地域茶叶中位值按中、东、西部分别为0.2006、0.1151、0.0675 mg/kg,茶叶高氯酸盐污染呈现显著的中高西低的情况(P <0.05);各茶类中位值分别为红茶0.0920 mg/kg、黑茶0.0618 mg/kg、绿茶0.1453 mg/kg、乌龙茶0.1183 mg/kg、白茶0.0920 mg/kg。各地区健康风险评估结果显示:中部地区的河南、湖北、湖南三省以及东部地区的广东省茶叶高氯酸盐危害商数(Hazard Quotient,HQ)值均大于1,而西部地区茶叶HQ值均小于1,说明中部地区的河南、湖南、湖北以及东部地区的广东省茶叶均存在高氯酸盐污染健康风险,应引起重视。根据健康风险评估结果,建议我国茶叶中高氯酸盐的最大残留限量值(maximum residue limit,MRL)可设为1.15 mg/kg。

High-performance liquid chromatography-tandem mass spectrometry was used to determine the contents of perchlorate in 279 tea samples in 15 provinces in the central,eastern,and western regions of China. The four-step method recommended by the US EPA was used to analyze the perchlorate contamination of tea samples in different regions for health risk assessment. The results showed that the total detection rate was 98.6%,the contents varied from ND( Not detected) to1.6466 mg/kg,the median value was 0.1138 mg/kg,the detected perchlorate excess rates( ≥ 0.75 mg/kg) was 3.9%.Regional results showed that the median value of tea in each region was 0.2006,0.1151,0.0675 mg/kg in the middle,east,and west,respectively.The perchlorate contamination of tea showed a significant middle-high-west low situation( P < 0.05).The median values of each kind of tea were 0.0920 mg/kg in black tea,0.0618 mg/kg in dark tea,0.1453 mg/kg in green tea,0.1183 mg/kg in oolong tea,and 0.0920 mg/kg in white tea.According to the results of health risk assessment,the HQ value of tea perchlorate in Henan,Hubei,Hunan provinces of central region and Guangdong province of eastern region were all greater than 1,and the HQ value of tea in the western region was less than 1,which showed that the health risks of perchlorate contamination in tea in Henan,Hunan,Hubei provinces of central region and Guangdong province of eastern region should be taken seriously.Based on the results of the health risk assessment,it was suggested that the maximum residue limit( MRL) of perchlorate in tea in China could be set to 1.15 mg/kg.