鄱阳湖平原地下水重金属含量特征与健康风险评估

Health risk assessment of groundwater heavy metal pollution in the Poyang Lake Plain

鄱阳湖平原作为长江中下游平原的重要组成部分,随着城镇化进程的快速推进,由于工矿业污染物、农村生活污水和农业生产废水向地下水的过量排放,农村地下水污染程度和范围不断扩大,为了解鄱阳湖平原地下水重金属污染状况,本研究在大量的水文地质调查和水化学样品测试基础上,分析该区地下水中重金属Cu、As、Cr、Hg、Pb、Cd含量特征,利用美国环境保护署(USEPA)的健康风险评价模型对鄱阳湖平原地下水重金属进行健康风险评价。研究区171个地下水样品中Cd、Cu、Hg、As、Pb、Cr等6种重金属元素含量变化幅度大,其中Hg、Cd和As平均值超过《地下水环境质量标准》(GB/T14848—2017)Ⅲ类标准,结果表明鄱阳湖平原地下水水质受人为影响大,局部地下水存在严重的污染。致癌物健康风险评价结果显示,Cr、As和Cd的平均个人年健康风险值均大于可接受风险值,Cr的健康风险值最大,是主要的致癌因子,As次之,Cd最低;非致癌物质健康风险结果显示,Hg、Pb和Cu的健康风险水平表现为Hg>Pb>Cu,属于可忽略风险。区域饮水途径上的健康风险主要来自致癌物质,总体上男性健康风险大于女性的健康风险。鄱阳湖平原地下水水质污染状况研究及治理监管工作提供理论依据,为其他区域地下水重金属的监测和质量控制提供参考和借鉴。

Groundwater in the Panyang Lake Plain(a major part of the Middle and Lower Reaches Plain of the Yangtze River)was found to be polluted due to industrial pollutants,rural sewage and agricultural wastewater with the rapid development of urbanization.More and more areas of rural groundwater suffered from pollution.The pollution situations became increasingly worse.In order to acquire the information on groundwater heavy metal pollution in the Pangyang Lake Plain,on the basis of abundant regional hydrogeologic surveys and detections of water samples,the contents of heavy metals(Cu,As,Cr,Hg,Pb and Cd)in the groundwater are analyzed to understand the pollution status of heavy metals in groundwater in the Poyang Lake Plain,and the health risk assessment model of the United States Environmental Protection Agency(USEPA)is used to evaluate the health risk level.The results show that the contents of Cd,Cu,Hg,As,Pb and Cr in 171 groundwater samples in the study area change greatly,and the average contents of Hg and Cd exceed the III standard value of groundwater environmental quality(GB/T 14848-2017).It is found that the groundwater quality of the Poyang Lake Plain is mainly affected by human being and the local groundwater is seriously polluted.The results of carcinogen health risk assessment show that the average annual health risk values of Cr,As and Cd are greater than acceptable risk values,and the health risk value of Cr is the largest,Cd is the lowest,indicating that Cr is the key factor for carcinogens risk.The non-carcinogenic health risk levels of Hg,Pb and Cu are Hg>Pb>Cu,and their risk can be ignored.The health risk of regional drinking water is mainly affected by carcinogens factor,and in generally,men’health risk is greater than that of women.This paper provides a theoretical basis for the research and management of groundwater quality pollution in the Poyang Lake plain area,and provides reference for the monitoring and quality control of heavy metals in other areas.