武汉市饮用水中有机污染物风险影响评价

目的 对武汉市饮用水中有机污染物含量进行调查和风险评估。方法 2013年至2017年,采集武汉市中心城区市政出厂水48件,测定《生活饮用水卫生标准》(GB5749-2006)规定的51种有机污染物及全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA)含量,运用健康风险评价模型进行风险概率评价。结果 共检出18种有机污染物,检出率高的污染物依次为三氯甲烷、PFOA、二氯一溴甲烷、一氯二溴甲烷、三氯乙醛、二氯甲烷。有机污染物通过饮水途径所致的非致癌风险为3.53×10-1²～1.14×10-9年-1,致癌风险为2.52×10-9～1.92×10-6年-1,其中一氯二溴甲烷和三氯甲烷的风险值之和占总风险值的比重大于85%。PFOA通过饮用水途径所致的非致癌风险与二氯一溴甲烷相当,仅次于一氯二溴甲烷和三氯甲烷。结论 武汉市饮用水中存在一定程度的有机物污染;有机物通过饮水途径所致非致癌健康风险可忽略,致癌健康风险低于ICRP推荐的最大可接受风险水平,但高于瑞典环境保护署、荷兰建设和环境署推荐的最大可接受风险水平。一氯二溴甲烷和三氯甲烷是健康风险值的主要贡献者,应作为饮用水风险管理的重点对象。

Risk assessment of organic pollutants in the drinking water,Wuhan

Objective To investigate the content of organic pollutants in the drinking water in Wuhan city and to assess the health risk caused by organic pollutants.Methods 48 pieces of municipal effluent from Wuhan downtown area were collected from 2013 to 2017.The contents of fifty-one organic pollutants,PFOS and PFOA,specified in hygienic standard for drinking water(GB5749-2006)were determined.With the data detected,risk probability evaluation of chemical contamination had been done using a health risk assessment model.Results 18 organic pollutants were detected.The detection rates were in sequence of trichloromethane,PFOA,dibromochloromethane,bromodichloromethane,trichloroacetaldehyde and dichloromethane.The non-carcinogenic health risk of organic pollutants through drinking water was between 3.52×10-1² and 1.14×10-9 per year,while the carcinogenic health risk was between 2.52×10-9 and 1.92×10-6 per year,with the health risk proportion of bromodichloromethane and trichloromethane over 85% in the total health risk.The non-carcinogenic health risk of PFOA was similar to that of dibromochloromethane,which is only lower than those of bromodichloromethane and trichloromethane.Conclusion Some organic contaminants are exiting in drinking water in Wuhan city.The non-carcinogenic health risk of organic pollutants caused by drinking water is negligible.The carcinogenic health risk of organic pollutants through drinking water is below maximum allowance levels recommended by ICRP,but it is over maximum allowance levels recommended by Swedish Environmental Protection Agency,Holland Construction and Environment Department.Bromodichloromethane and trichloromethane are the main contributors to health risk and should be the focus of risk management for drinking water.