昆山市生活饮用水金属污染物的致癌性风险评价

Carcinogenic risk induced by metal pullutants in drinking water in Kunshan

目的评价昆山市生活饮用水致癌性金属污染物的暴露水平及人群致癌性风险。方法收集2010—2015年间昆山市末梢水和出厂水中铬(六价)、砷、镉3种致癌性金属元素的监测数据,按照美国环保局饮用水途经暴露健康风险评价模型对其致癌性健康风险进行评价。结果 2010—2015年间共监测出厂水32份,末梢水252份,3种金属监测结果均符合《生活饮用水卫生标准》(GB5749-2006)的限值要求。铬(六价)、砷、镉在出厂水和末梢水中总致癌风险(R总)分别为71.94×10^(-6)/年和53.98×10^(-6)/年,以六价铬的危害最大,风险排序均为R_(六价铬)>R_砷>R_镉。结论昆山市饮用水中3种金属污染物的总体致癌性风险处于美国EPA认定的可接受风险水平(1×10-6~1×10^(-4)/年)之间,但依然有潜在的风险。

Objective To investigate the exposure level of carcinogenic metal elements in drinking water in Kunshan city and its potential carcinogenic risk for human health in Kunshan. Methods The surveillance data of three carcinogenic metal elements（Cr^6＋ , As, Cd） in all treated water samples and tap water samples were collected in Kunshan city from 2010 to 2015. Their carcinogenic risk was assessed according to the drinking water exposure pathway health risk assessment model recommended by the United States Environmental Protection Agency（USEPA）. Results The quality of all indicators measured for 32 treated water samples and 252 tap water samples were below the limits of the National Standards for Drinking Water Quality （GB5749-2006） . The health risk on three carcinogenic heavy metals（As, Cd,Cr6＋ ） for treated water samples and tap water samples were 71.94× 10^-6/a and 53. 98× 10^-6/a respectively. The harm of Cr6＋ was the most serious in the three metals. The rank of health risk was Cr^6＋ 〉As〉 Cd. Conclusion The total health risk of the three metal elements were in the range of acceptable levels by USEPA （1 × 10^-6/a-1 × 10^-4/a）. However, there are still potential risks.