银山矿区水环境中重金属污染以及健康风险评价

Pollution Characteristics and Health Risk Assessment of Heavy Metals in Water Environment of Yinshan Mining Area

为研究湖北省阳新县银山铅锌矿区水环境中重金属污染状况,分别采集44个地下水和16个地表水进行重金属测定分析。农用地地下水中重金属污染元素依次是As,Pb,Cu,Ni和Cd;建设用地地下水中重金属污染元素依次为As,Ni,Cd,Cu和Pb;地表水中重金属污染元素分别是As,Cd,Ni,Pb和Cu。除Cu含量比较接近外,地表水中As,Cd,Ni和Pb含量均高于农用地和建设用地地下水;建设用地地下水中As含量远远低于农用地地下水,Cu,Ni和Cd含量高于农用地地下水,Pb含量二者非常接近。该矿区重金属分布情况体现不同类型地区水体中重金属污染空间差异性。该矿区水环境中As含量较高,基本覆盖整个矿区;建设用地地下水和地表水中Cd污染严重,推测是泄露废水和回填废渣造成。健康风险评价结果表明,建设用地地下水和地表水中Cd对儿童存在可接受致癌风险;建设用地和农用地地下水以及地表水中As对成人和儿童存在不可接受的致癌风险,并且对于儿童致癌风险均高于成人。

To study the pollution status of heavy metals in water of Yinshan lead-zinc mining area in Yangxin county of Hubei province,44 groundwater samples and 16 surface water samples were respectively collected for the determination and analysis of heavy metals.Heavy metals in groundwater of farmlands presented the following order As,Pb,Cu,Ni and Cd.While,the order of As,Ni,Cd,Cu and Pb was found in groundwater of constructive lands,and that of As,Cd,Ni,Pb and Cu was found in surface water.Cu had the close concentrations between the groundwater and surface water.But,the concentrations of As,Cd,Ni and Pb in surface water were higher than those in groundwater of farmlands and constructive lands.Pb had the close concentrations between the groundwater of farmlands and constructive lands.But,the As concentrations in groundwater of constructive lands were less than those in groundwater of farmlands.The concentrations of Cu,Ni and Cd in groundwater of constructive lands were higher than those in groundwater of farmlands.The distribution of heavy metals in the mining area suggested the spatial differences for heavy metal pollution in different water environment.The area was found with higher As concentrations basically covering the whole study area.The serious Cd pollution was found in groundwater of constructive lands and surface water,speculating caused by the leakage of waste water and backfilled waste.The result of health risk assessment indicated that Cd in groundwater of constructive lands and surface water showed acceptable risks of cancer for children.As in groundwater and surface water showed unacceptable risks of cancer for children and adults.Moreover,the risks of cancer for children were larger than those for adults.