2015年中山市饮用水源水中化学污染物健康风险评价

Health risk assessment of chemical contaminants in drinking water sources in Zhongshan in 2015

目的了解中山市饮用水源水中化学污染物的含量,并评价其对人体健康产生的潜在风险。方法于2015年1—12月,每个季度对中山市分布在7个河道及8个中小型水库的24个市政水厂的水源水进行采样和检测,采用美国国家环境保护局(US EPA)推荐的健康风险评价模型对水源水中5种致癌性化学物(砷、六价铬、镉、三氯甲烷和四氯化碳)和12种非致癌性化学物(铅、汞、硒、氰化物、氟化物、硝酸盐、铁、氨氮、锰、铜、锌和挥发酚)通过饮水途径所引起的健康风险进行初步评价。结果中山市饮用水源水中17种化学污染物所引起的总健康风险为3.75×10^(-5)/年,以六价铬和砷的致癌风险为主(致癌风险分别为2.69×10^(-5)/年和1.05×10^(-5)/年),占总健康风险的99.73%。致癌性化学物所引起的个人致癌风险由高至低分别为六价铬>砷>镉>四氯化碳>三氯甲烷,致癌总风险为3.75×10^(-5)/年。非致癌性化学物所引起的个人非致癌风险由高至低分别为氟化物>硝酸盐>铁>铅>锰>氨氮>硒>汞>铜>锌>挥发酚>氰化物,非致癌总风险为22.69×10^(-10)/年。结论中山市饮用水源水中17种化学污染物对人体健康产生的个人健康风险水平均在国际辐射防护委员会(ICRP)规定的最大可接受风险水平(5.0×10^(-5)/年)范围内,六价铬和砷是优先控制的化学污染物。

Objective To understand the content of chemical contaminants in drinking water sources in Zhongshan,and evaluate the potential risk to human health. Methods The concentrations of five genetic toxic chemicals(As,Cr6+,Cd,CHCl3,CCl4) and 12 non-carcinogenic chemincals(Pb,Hg,Se,CN-,F-,NO3-,Fe,NH3-N,Mn,Cu,Zn,volatile phenol) in water source from 24 centralized water supply systems distributed in seven rivers and eight small reservoirs in Zhongshan were determined in each season from January to December,2015. The health risk of exposure to chemical contaminants through drinking water was assessed based on the models recommended by the U.S. Environmental Protection Agency(US EPA). Results The total health risk caused by 17 chemical contaminants in drinking water sources was 3.75 ×10-5 per year in Zhongshan, 99.73% of which consisted of carcinogenic risk caused by Cr6+(2.69×10-5 per year) and As(1.05×10-5 per year). The carcinogenic risk caused by genetic toxic chemicals for the individual was in the order of Cr6+>As>Cd>CCl4>CHCl3,totally amounted to 3.75×10-5 per year.The non-carcinogenic risk caused by non-carcinogenic chemicals for the individual was in the order of F->NO3->Fe>Pb>Mn>NH3-N>Se>Hg>Cu>Zn>volatile phenol>CN-,totally amounted to 22.69×10-10 per year. Conclusion The health risk caused by17 chemical contaminants in drinking water sources are below the maximal acceptable value recommended by International Commission on Radiological Protection(ICRP)(5.0 ×10-5 per year) in Zhongshan,As and Cr6+should be controlled in high priority.