天津市地下水重金属来源解析及健康风险评估

Source analysis and health risk assessment of heavy metals in groundwater of Tianjin

中文关键词: 地下水  重金属  来源解析  风险评价

英文关键词: groundwater  heavy metals  source analysis  risk assessment

中文摘要:

      为了解天津市地下水环境状况，对采集到的 93组地下水样品中 9种重金属元素进行测定(Mn、Cu、Zn、As、 Se、Cd、Pb、Ba、Ni)，运用多种统计分析和综合评价法了解重金属的分布和污染状况，并结合健康风险模型对不同途径所引起的健康风险进行评价。结果表明:①研究区地下水重金属含量平均值排序为 Mn>Ba> Zn>As>Se>Cu>Ni>Pb>Cd，Mn、As、Ba含量平均值超出国家 II级标准，其余重金属含量平均值符合国家 I级标准；②研究区地下水受到 Mn、Se、As、Ba的污染，Zn、Cu、Ni、Pb、Cd在各点位均无污染；③研究区地下水中 Ni、Cu、Zn主要来源于工农业及交通污染，Pb、Cd可能是自然源，Ba、As、Mn、Se可能同时受人类活动和自然因素影响；④健康风险评价结果显示研究区地下水致癌风险主要受 As影响，主要影响途径为饮用途径，成人和儿童的终身致癌风险均大于最大可接受风险水平(1×10-4 a-1)；地下水非致癌风险主要受 As、Se影响，饮用途径风险大于皮肤接触途径，成人风险大于儿童风险。成人和儿童通过 2种途径暴露的综合非致癌风险值(HI)均高于安全限值 1。

英文摘要:

      In order to investigate the groundwater environment in Tianjin City. Nine heavy metal elements (Mn,Cu, Zn, As, Se, Cd, Pb, Ba, Ni) in 93 groundwater samples were detected. Multiple statistical analysis and compre-hensive evaluation methods were used to study the distribution and pollution of heavy metals. The health risk mod-els were used to evaluate the health risks caused by different exposurepathways. The results showed that: The aver-age values of heavy metal contents in descending order were Mn>Ba>Zn>As>Se>Cu>Ni>Pb>Cd. The average con-tents of Mn, As and Ba exceeded the national level II standard, and the average contents of other heavy metals werelower than the national level I standard.The groundwater was polluted by Mn, Se, As, Ba.Ni, Cu, and Zn in thegroundwater mainly came from industrial, agricultural, and traffic pollution. Pb and Cd influenced by naturalsources. Ba, As, Mn, and Se influenced by both human activities and natural factors. The carcinogenic risk ofgroundwater was mainly affected by As, with the main influencing pathway being the drinking route.The lifetimerisk of cancer in both adults and children was greater than the maximum acceptable risk level (1×10-4·a-1). The non-carcinogenic risk of groundwater was mainly affected by As and Se. The non-carcinogenic risk of drinking is greaterthan that of skin contact, and the risk in adults is greater than that in children.The non-carcinogenic risk values ofboth adults and children exposed through two pathways are higher than the safety limit of 1.