茶叶中铝、铅、砷、汞、铬、镉含量的分析及危害评价

目的研究福建省市售茶叶中金属元素含量情况,通过分析茶叶中重金属含量情况,评估其对人体的健康风险情况。方法在福建省市场随机抽取不同品种茶叶98份,用微波消解法处理茶叶,电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS)检测茶叶中铝、铅、砷、汞、铬、镉的含量。结果98批市售茶叶中的铅、砷、汞、铬、镉5种重金属元素含量都在国家标准范围之内,目前暂无茶叶中铝含量相关限量标准,但其危害作用有限。98份市售茶叶中铅、砷、铬、铝检出率均为100%,铬、汞的检出率分别为95.9%、37.8%。各元素靶标危害系数(target hazard quotient,THQ)排名依次为铝>铬>砷>铅>镉>汞,危害指数(hazard Index,HI)为0.2589,铝对危害指数的贡献率为45.2%。按照不同茶叶种类进行分类,其危害指数排名依次为黑茶>乌龙茶>绿茶>红茶。按照茶叶产地进行分类,其危害指数排名依次为云南>福建>浙江。结论福建省市售茶叶中这6种金属元素存在一定程度的污染,但危害指数为0.2589,小于1,对人们的健康风险较低,但仍应持续监测茶叶中金属元素的含量情况。

Analysis and hazard evaluation of aluminium, lead, arsenic, mercury, chromium and cadmium content in tea

Objective To study the content of heavy metal elements in tea in Fujian province, explore the content of heavy metals in different types of tea, and assess the health risks to the population. Methods A total of 98 tea samples were randomly collected from markets of Fujian province to detect the content of heavy metals (aluminum, lead, arsenic, mercury, chromium and cadmium) by inductively coupled plasma mass spectrometry after microwave digestion. Results The content of lead, arsenic, mercury, chromium and cadmium in the 98 tea samples was within the national standard. Aluminum limited content had no requirement in the national standard, but the damage was limited. The detection rates of lead, cadmium arsenic and aluminum were all 100.00%, and the detection rates of chromium and mercury were 95.9% and 37.8%, respectively. Target hazard quotient of each element (THQ) rank was aluminum>chromium>arsenic>lead>cadmium>Hg, hazard index (HI) was 0.2589, and the contribution of aluminum to the hazard index was 45.2%. According to the harm index of different tea types, harm index rank was dark tea>oolong tea>green tea>black tea. According to the origins of tea, harm index rank was Yunnan province>Fujian province>Zhejiang province. Conclusion There is a certain degree of metal pollution in the tea sold in Fujian province, but the hazard index is 0.2569, which is less than 1. The health risk is low, but the heavy metals in tea still need to be monitored continuously.