郑州市售代用茶中7种重金属含量污染状况调查

Investigation of 7 elemental pollution in substitutional tea commercially available in Zhengzhou

目的通过本次调查了解郑州市市售代用茶中Pb、Cd、Cr、As、Hg、Ni、Al 7种重金属含量水平及超标情况,为标准制修订提供科学依据。方法随机在郑州市大型商超、药店及茶叶市场采集代用茶样品86份。使用微波消解处理样品,电感耦合等离子体质谱法测定代用茶中Pb、Cd、Cr、As、Hg、Ni、Al 7种重金属含量,对数据进行分类整理与分析。结果代用茶中Pb检出率为98. 8%,均值为0. 415 mg/kg; As检出率为48. 8%,均值为0. 171 mg/kg,Cd检出率为66. 3%,均值为1. 54 mg/kg。Al检出率为100%,均值为54. 9 mg/kg; Ni检出率为70. 9%,均值为2. 58 mg/kg; Cr检出率为52. 3%,均值为0. 575 mg/kg; Hg检出率为17. 4%,均值为0. 009 mg/kg。结论代用茶中Pb、Al检出率很高,具有潜在风险;苦丁茶中Cd含量严重超出限量标准,菊花茶中砷含量较高,两种代用茶存在潜在的安全风险,应引起重视。

Objective To provide scientific basis for the revision of stand system by investigating the content level and exceeding standard rates of seven elements, including Pb, Cd, Cr, As, Hg, Ni and A1 in substitutional tea commercially available in Zhengzhou. Methods 86 samples were collected randomly from shopping malls, pharmacies and tea markets in Zhengzhou, the contents of seven elements were determined by inductively coupled plasma mass spectrometry（ICP- MS） ＇after microwave digestion and the results were sorted and analyzed. Results The detection rate of Pb in the tea samples was 98.8%, with the average content of 0. 415 mg/kg; the detection rate of As was 48.8%, with the average content of 0. 171 mg/kg; the detection rate of Cd was 66.3% , with the average content of 1.54 mg/kg; AI was detected in all the samples, with the average content of 54.9 mg/kg; the detection rate of Ni was 70.9% , with the average content of 2.58 mg/kg; the detection rate of Cr was 52.3% , with the average content of 0. 575 mg/kg; the detection rate of Hg was 17.4% , with the average content of 0.009 mg/kg. Conclusion Pb and A1 exhibited notably high detection rates, indicating a potential risk. Cd content in broadleaf holly leaf exceeded the national standard seriously and higher content of As was found in the chrysanthemum tea, indicating a potential risk of intake safety which should be taken into account.