常见茶叶中14种元素含量分析及重金属风险评价

采集传统名茶地标产品样品各3种为实验样品,通过ICP-OES和ICP-MS对样品进行K、Ca、Mg、Mn、B、Cu、Fe、Ni、Zn、Cr、Co、Cd、As、Pb等14种元素的含量测定。利用单因素方差分析、主成分分析、污染评价等方法,对茶叶无机元素含量进行分析和污染评价,并对污染来源进行了研究。结果表明,不同产地茶叶样品中的K、Ca、Mg、Mn、Fe等元素含量差异较大;食品及茶叶安全限量元素Cd、Cr、Pb、As等实测值均未超过国家标准限值;部分元素之间具有正相关性,如Cu与Cd, Cu与Ni, As与Ni两两之间关联性较强;从主成分分析看出Cu、Cd、As和Ni为PC1代表因子,K和Fe分别为PC2和PC3的代表因子,PC1主要代表了金属冶炼、工业排放和垃圾焚烧等方面的贡献,PC2和PC3分别代表了肥料施放和茶叶加工等方面的贡献。

The Content Analysis of 14 Elements and Risk Evaluation of Heavy Metals in Common Teas

By using ICP-OES and ICP-MS, the contents of 14 elements of the experimental samples, including K, Ca, Mg, Mn, B, Cu, Fe, Ni, Zn, Cr, Co, Cd, As and Pb, had been determined. These experimental samples had been obtained by collecting three kinds of traditional "ten famous tea landmark products". One-way ANOVA, the principal component analysis and the pollution evaluation were used to study the content of inorganic elements, as well as the source of pollution. The results showed that the contents of K, Ca, Mg, Mn, Fe in tea samples from different areas were significantly different. Cd, Cr, Pb, As did not exceed the national standards for the food safety limit. A partial positive correlation existed between Cu and Cd, Cu and Ni, As and Ni pairwise. The principal component analysis showed that Cu, Cd, As and Ni were the representative factors of PC1, whereas K and Fe were the representative factors of PC2 and PC3, respectively. PC1 mainly represented the contributions of metal smelting, industrial discharge and waste incineration, while PC2 and PC3 represented the contributions of fertilizer application and tea processing, respectively.