基于污染源导向的庐江县地表水中金属元素健康风险评估

Source-oriented health risk assessment of metal elements in surface water in Lujiang County

水体金属污染对人体健康构成严重威胁,建立金属污染源与健康风险间的关联对金属污染的精准治理至关重要.在安徽省庐江县采集177个地表水样品并测定14种金属元素浓度,采用绝对主成分得分-多元线性回归(APCS-MLR)和基于蒙特卡罗模拟(Monte Carlo simulation)的健康风险评估模型识别地表水中金属的污染源并评估其健康风险.结果表明,庐江县地表水中Al、Be、Co、Cr、Cu、Fe、Mg、Mn、Ni、Pb、Sn和Zn的平均浓度北高南低,Sr呈相反的空间分布特征,而As的空间差异不明显.Be、Fe、Mn和Ni的平均浓度超过《地表水环境质量标准》(GB3838-2002)中的Ⅲ类水质类别限值.APCS-MLR确定了3个污染源,包括交通源、自然源以及农业与矿业混合源,方差贡献率分别为41.94%、18.06%、11.23%.交通源对所有人群造成致癌与非致癌风险的概率均超过80%,对健康风险的贡献率也高于50%.摄入率(IR)和体重(BW)是控制婴儿和儿童健康风险的最敏感参数,Ni和Be浓度分别是导致其他年龄段居民高致癌和非致癌风险的关键元素.

Metal pollution in water poses a serious threat to human health,emphasizing the need to establish correlation between metal pollution sources and health risks for accurate control of metal pollution.In this study,177 surface water samples were collected from Lujiang County,Anhui Province,and analyzed for the concentrations of 14 metal elements.The absolute principal component score-multiple linear regression(APCS-MLR)and health risk assessment model based on Monte Carlo simulation were used to identify the sources of metal elements in surface water and assess their health risks.The results revealed spatial variations in metal concentrations in surface water,with higher mean concentrations of Al,Be,Co,Cr,Cu,Fe,Mg,Mn,Ni,Pb,Sn and Zn in surface water in the north and lower in the south.Conversely,the spatial distribution characteristics of Sr showed opposite trend,and the spatial differences of As were not obvious.Additionally,The average concentrations of Be,Fe,Mn and Ni exceeded the limits set by the Surface Water Environmental Quality Standards of China(GB3838-2002)for Class Ⅲ water quality.Three metal sources were identified by APCS-MLR,including traffic source,natural source,agricultural and mining mixed source,with the variance contribution rates of 41.94%,18.06%and 11.23%,respectively.The traffic source was found to be the most significant contributor to both carcinogenic and non-carcinogenic risks,with probabilities exceeding 80%,and its contribution rate to health risk was also more than 50%.For infants and children,health risks were most sensitive to Intake rate(IR)and body weight(BW),while in other age groups,Ni and Be concentrations were key factors leading to high carcinogenic and noncarcinogenic risks,respectively.