铜仁矿区农村地下饮用水重金属含量与健康风险评价

Heavy Metal Content and Health Risk Assessment of Underground Drinking Water in Rural Areas of Tongren Mining Area

为探明铜仁矿区农村地下饮用水重金属含量特征,于2018年1月和5月对铜仁松桃锰矿区和万山汞矿区的地下饮用水中重金属含量进行分析检测,并运用USEPA推荐的健康风险模型对研究区地下饮用水进行健康风险评价。结果表明:除W2号样点Hg超标外,其余各样点9种重金属含量均符合《生活饮用水卫生标准》(GB5749—2006),万山汞矿区地下饮用水重金属平均含量均远超于松桃寨英锰矿区。Pearson相关性分析表明,Zn与Cr、Cd、Pb、Cu、Ni、Mn均存在极显著正相关,相关系数分别为0.414、0.614、0.589、0.428、0.714、0.445,As与Cu存在极显著正相关,相关系数为0.489,As与Cr、Hg之间存在显著正相关,相关系数分别为0.339、0.333。USEPA健康风险评价表明,非化学致癌物对成人和儿童所致健康危害风险均值集中在10^(-12)～10^(-10)之间,均属于可忽略水平;化学致癌物Cr和As对成人和儿童所引起的健康风险的均值均超过瑞典环境保护署、荷兰建设与环境部和英国皇家协会推荐的健康风险等级(1.0×10^(-6)),儿童人群总致癌风险在3.08×10^(-6)～1.48×10^(-4)/a之间,明显高于成人2.66×10^(-6)～1.28×10^(-4)/a的水平。Cr和As为铜仁矿区地下饮用水的主要污染物,应予以优先关注和管控。

In order to prove the heavy metal content of rural underground drinking water in Tongren Mining Area,the heavy metal content of underground drinking water in Tongren Songtao Manganese Mine and Wanshan Mercury Mine Area is analyzed in January 2018 and May,and the USEPA recommended health risk model is used to evaluate the health risk of underground drinking water in the research area. The results show that 9 kinds of heavy metal contents in the other points are in accordance with 'Sanitary Standard for Drinking Water'( GB5749-2006) except for the Hg exceeding the standard at W2 number,and the average content of heavy metals in the underground drinking water in Wanshan Mercury mine area is much more than that in Songtao-manganese mine. Pearson correlation analysis shows that Zn is significantly positively correlated with Cr,Cd,Pb,Cu,Ni and Mn,and the correlation coefficients are 0.414,0.614,0.589,0.428,0.714,and 0.445.There is a significant positive correlation between As and Cu,with a correlation coefficient of 0.489. There is a significant positive correlation between As and Cr and Hg,and the correlation coefficients are 0.339 and 0.333 respectively. The USEPA health risk assessment showed that the average value of the risk of health hazard caused by non-chemical carcinogens in adults and children is 10-12~ 10-10,which is negligible.The mean risk of health risks caused by chemical carcinogens,Cr and As,to adults and children exceeds the health risk rating( 1.0×10-6)recommended by the Swedish Environment Protection Agency,the Dutch Ministry of Construction and Environment and the Royal Society.The total cancer risk in children is 3.08×10-6~ 1.48×10-4/a,which is significantly higher than the adult level( 2.66×10-6~ 1.28×10-4/a).Cr and As are the main pollutants of underground drinking water in Tongren Mining Area.