福建主产乌龙茶中无机砷的分析与风险评价

Analysis and risk assessment of inorganic arsenic in Oolong teas cultivated in Fujian province

目的评价乌龙茶中的无机砷含量,并对无机砷的暴露风险进行评估。方法收集春、夏、秋3个季节采摘的8个福建省主栽乌龙茶品种,采用微波辅助消解-固相萃取-氢化物产生原子荧光光谱法(microwave assisted digestion-solid phase extraction-hydride generation-atomic fluorescence spectrometry,MAD-SPE-HG-AFS)测定其无机砷含量并进行无机砷暴露风险评估。结果乌龙茶中无机砷的含量在0.037~0.050 mg/kg之间,平均含量为0.043 mg/kg,其中秋季采摘的武夷水仙茶叶中的无机砷含量最高。方差分析结果表明,不同季节采摘的乌龙茶中无机砷含量差异不显著,而同一季节不同乌龙茶品种中无机砷含量存在显著差异。依据美国环境保护署(United States Environmental Protection Agency,USEPA)规定的每日无机砷摄入限量(reference dose,RfD=0.3μg·(kg·bw)^(-1)·d^(-1))评价表明,人体通过乌龙茶无机砷的每日暴露量(estimated daily intake,EDI)为6.80E-07~9.19E-07 mg/(kg·d),乌龙茶中无机砷含量的危害商值(hazard quotient,HQ)值均小于1。结论福建省主栽乌龙茶品种中无机砷含量低,通过摄入乌龙茶导致消费者无机砷暴露的风险极低。

Objective To analyze inorganic arsenic contents in Oolong teas, and evaluate to the exposure risk of inorganic arsenic. Method Totally 8 varieties of Oolong tea were collected from Fujian in 3 seasons of spring, summer and autumn. The content of inorganic arsenic was determined by microwave assisted digestion-solid phase extraction-hydride generation-atomic fluorescence spectrometry （MAD-SPE-HG-AFS） and risk assessment was conducted based on the above data. Results The contents of inorginc arsenic in Oolong tea were in the range of 0.037-0.050 mg/kg while the mean value was 0.043 mg/kg. The ＂Wuyi Shuixian＂, which was collected in autumn, had the highest inorganic arsenic content. Meanwhile, variance analysis showed that no significant difference of inorganic arsenic contents among different cultivated seasons, but significant difference in varieties. Furthermore, according to the regulation of United States Environmental Protection Agency （USEPA） on the oral reference dose for inorganic arsenic （RfD=0.3μg.（kg.bw）-l.d-l）, the estimated daily intake （EDI） of inorganic arsenic in Oolong tea was 6.80E-07-9.19E-07 mg/（kg＇d）, while the hazard quotient （HQ） were below 1 arsenic content of oolong tea in main varieties of Fujian province are low, and the arsenic for consumers is very low through Oolong tea intake. Conclusion The inorganic risk of exposure to inorganic