广西某城市饮用水水源地重金属健康风险评价

摘要

In order to clarify the health risk levels of heavy metals in drinking water sources of city ,based on water quality monitoring data from the main three drinking water sources in one city of southern Guangxi ,the health risk assessment model of US EPA is employed to assess the health risk of Cr ,As ,Cd ,Pb ,Cu ,Hg ,Fe and Zn via drinking water ingestion path-way .The results indicate that total non-carcinogenic risks of non -carcinogens for adult and children are both between 10-10~10-9 a-1 ,much lower than the maximum acceptable level recommended by US EPA (10-4 a-1 );the order of car-cinogenic risks caused by carcinogenic for adult and children are both Cr>As>Cd;total carcinogenic risks of river type , lake and reservoir type drinking water sources exceed the maximum acceptable level recommended by US EPA (10-4 a-1 ) and total carcinogenic risks of children are between 8 .43 × 10-5 ~6 .26 × 10-4 a-1 ,much higher than that of the adult , between 6 .05 × 10-5~4 .52 × 10-4 a-1 .Cr contributes highest total carcinogenic risks to adult and children and it is the main carcinogenic .%为阐明城市饮用水水源地重金属污染物的健康风险水平 ,根据广西某市主要的3处饮用水水源地水质监测结果 ,采用美国环境保护署(US EPA )推荐的健康风险评价模型 ,对水源地原水中Cr、As、Cd、Pb、Cu、Hg、Fe和Zn等重金属通过饮用水途径引起的环境健康风险进行评价.结果表明 :非致癌物质对成人和儿童引起的总非致癌风险在10-10~10-9 a-1之间 ,远低于US EPA推荐的最大可接受风险水平(10-4 a-1 );致癌物质对成人和儿童引起的人均年致癌风险大小顺序均为Cr>As>Cd;河流、湖库型水源地总致癌风险均超过US EPA推荐的最大可接受风险水平(10-4 a-1 ) ,其中儿童人群总致癌风险在8 .43 × 10-5 ~6 .26 × 10-4 a-1之间 ,明显高于成人6 .05 × 10-5~4 .52 × 10-4 a-1的水平.Cr对儿童和成人总致癌风险贡献最高 ,是最主要的致癌物.