东莞市某地区地表水中重金属健康风险不确定性评价

为了解东莞市西南地区(麻涌镇、沙田镇、虎门镇和长安镇)地表水中重金属污染现状与健康风险水平,对研究区域内29个地表水样中As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等重金属元素进行测定,并运用不确定性健康风险评价模型对研究区地表水中的重金属进行健康风险评估。结果表明:该研究区域地表水中重金属引起的致癌风险较高,人均年健康风险都在Ⅴ级风险及以上。化学致癌性重金属引起的人均年健康风险中,以Cr最大,As次之,然后是Cd。非化学致癌性重金属引起的人均年健康风险中,Pb的风险最大,Ni次之,风险均远小于化学致癌性重金属引起的人均年健康风险。因此,该研究区域地表水中重金属健康风险管理应以化学致癌风险为主,重金属污染物的优先控制顺序为CrAsCd。

Uncertainty Evaluation on Health Risk of Heavy Metal Elements in Surface Water of Dongguan, Guangdong Province

To better understand the pollution status of heavy metal elements in surface water and the health risk level of the regions of Machong, Shatian, Humen, and Changan town in the southwest of Dongguan city, the concentrations of heavy metal elements As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn of 29 surface water samples from the study area were analyzed, and the health risk assessment of heavy metal pollution in surface water of the study area was undertaken using the uncertainty health risk assessment model. Our results showed that the carcinogenic risk from heavy metal pollution in surface water of the area is relatively high, with a grade of per capita annual health risk larger than level V. The per capita annual health risk caused by chemical carcinogenic heavy metal elements follows the order of Cr>As>Cd, while it caused by non-chemical carcinogenic heavy metal elements follows the order of Pb>Ni. However, the per capita annual health risk caused by non-chemical carcinogenic heavy metal elements is notably lower than that by chemical carcinogenic heavy metal elements. In summary, health risk management for heavy metal pollution in surface water of the area should focus on chemical carcinogenic risk, and the controlling precedence of heavy metal pollution follows the sequence of Cr>As>Cd.