宝鸡市区生活饮用水重金属空间分布及风险评价

Heavy Metal Spatial Distribution and Risk Assessment of Drinking Water in Baoji City

为研究宝鸡市区生活饮用水重金属空间含量分布特征及风险水平,在宝鸡市区采集110个饮用水样,对水样中重金属(Cr、Cd、As、Mn、Pb、Cu、Zn、Ni)含量采用ICP-MS测定,采用水质污染指数(HPI)和US EPA健康风险模型对饮用水水质进行综合评价,并基于GIS对健康风险等级进行了可视化表述。结果表明:生活饮用水水质污染指数(HPI)在阈值风险(100)以下,各重金属含量均值均在《生活饮用水卫生标准》规定范围内,但Cu、Ni、Cr、Pb的浓度最大值都超过《生活饮用水卫生标准》的限值;通过饮水途径所造成的致癌重金属人均年健康风险顺序为Cr>As>Cd,非致癌重金属人均年健康风险顺序为Mn>Pb>Cu>Zn>Ni。宝鸡市区生活饮用水重金属总健康风险高值区主要集中于金台区中部和北部,重金属健康风险以致癌风险为主,Cr是首要风险因子。据此,可为宝鸡市区生活饮用水水质安全和水质风险管理提供科学依据。

In order to study the spatial distribution characteristics and risk level of heavy metals in drinking water in Baoji City,Shaanxi Province,110 drinking water samples were collected,and the contents of heavy metals(Cr,Cd,As,Mn,Pb,Cu,Zn,and Ni)in water samples were collected as well.The ICP-MS was used to measure the quality of drinking water using the heavy metal pollution index(HPI)and the US EPA health risk model.Based on GIS,the health risk grades were visually represented.The results showed that average heavy metal content of drinking water are all within the scope of the Sanitary Standard for Drinking Water,but the maximum concentrations of Cu,Ni,Cr,and Pb exceed the limits of the standard;the water pollution index(HPI)is at the threshold risk(100).The per capita annual health risk of carcinogenic heavy metals caused by drinking water pathways is Cr>As>Cd,and the per capita annual health risk of non-carcinogenic heavy metals is Mn>Pb>Cu>Zn>Ni.The high-risk areas are mainly concentrated in the central and northern parts of Jintai District.The health risk of heavy metals is mainly caused by cancer risk,with Cr as the primary risk factor.The study would provide a scientific basis for the drinking water risk management,water safety and water quality in Baoji City.