西藏4地市糌粑中重金属含量分析与污染评价

Analysis of Heavy Metals Content and Pollution Evaluation in Tsamba in Four Cities of Tibet

摘要:

通过调查西藏4地市（山南市、日喀则市、林芝市、拉萨市）不同磨制方式生产的糌粑中重金属砷（As）、镉（Cd）、铬（Cr）、铅（Pb）、汞（Hg）含量，并开展污染情况全面分析评价，以提高西藏各地市糌粑的质量安全水平，为加强质量安全监管提供可靠的数据支持。从西藏4地市分别采集不同模式生产的糌粑样品101个，使用电感耦合等离子体质谱法对糌粑样品中5种重金属进行检测分析与质量安全评价。101个糌粑样品中，按照糌粑质量分级标准综合污染指数进行评价，不同磨制方式生产糌粑中应用单因子污染指数、综合污染指数评价结果显示，电磨和水磨糌粑中的重金属As 、Cd 、Cr、Pb、Hg污染等级均属于安全。不同地市生产糌粑中单因子污染指数及综合污染指数评价结果显示，山南市糌粑中的重金属Pb污染等级属基本清洁，As 、Cd 、Cr、Hg污染等级均属安全；日喀则市糌粑中的重金属As污染等级属基本清洁，Cd 、Cr、Pb、Hg污染等级均属安全；林芝市糌粑中的重金属Pb污染等级属基本清洁，As 、Cd 、Cr、Hg污染等级均属安全；拉萨市糌粑中的重金属Pb、As 、Cd 、Cr、Hg污染等级均属安全；根据Nemerow综合污染等级评价4地市中的其他重金属综合污染指数等级均是安全。因此，西藏4地市糌粑中的重金属As 、Cd、Cr、Pb、Hg综合污染指数等级均是安全。

Abstract:

Through investigating the contents of heavy metals arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), and mercury (Hg) in tsamba produced by different grinding methods in four cities in Tibet (Shannan, Xigaze, Nyingchi and Lhasa), and conducting a comprehensive analysis and evaluation of pollution levels, reliable data support could be provided to enhance the quality and safety level of tsampa production and strengthen quality and safety supervision. A total of 101 samples of tsamba produced in different modes were collected from four cities in Tibet. And inductively coupled plasma mass spectrometry was utilized to detect and analyze five heavy metals in tsamba samples, and to evaluate their quality and safety. Among 101 tsamba samples evaluated using the comprehensive pollution index of tsamba quality grading standard, both electric mill and water mill methods yielded safe levels of heavy metals including As, Cd, Cr, Pb, and Hg in tsamba, based on the evaluation results of single factor pollution index and comprehensive pollution index in the production of tsamba prepared by different grinding methods. Based on the evaluation results of the single factor pollution index and comprehensive pollution index in the production of tsamba in different cities, it could be concluded that the heavy metal Pb in tsamba in Shannan city is basically clean, and As, Cd, Cr, and Hg are all safe. The heavy metal As in tsamba in Xigaze city is basically clean, and Cd, Cr, Pb, and Hg are all safe. The heavy metal Pb in tsamba in Nyingchi city is basically clean, and As, Cd, Cr, and Hg are all safe. The heavy metals Pb, As, Cd, Cr, and Hg in tsamba in Lhasa city are all safe. According to the Nemerow comprehensive pollution level evaluation, the comprehensive pollution index levels of other heavy metals in the four cities are all safe. Therefore, the comprehensive pollution index levels of heavy metals such as As, Cd, Cr, Pb, and Hg in tsamba in four cities of Tibet are all safe.