北京市政供水中三氯甲烷和四氯化碳含量分析及健康风险评估

目的 了解南水北调之后北京市市政水中三氯甲烷和四氯化碳的浓度水平,评估其对人体健康的潜在风险.方法 收集了 2015-2019年北京市出厂水、末梢水和二次供水中三氯甲烷和四氯化碳的监测数据,利用美国环保局(USEPA)推荐的健康风险评价四步法模型对其进行健康风险评估.结果 4 292件监测水样中,三氯甲烷平均浓度为0....

Concentrations and health risk assessment of trichloromethane and carbon tetrachloride in municipal water supply of Beijing

Objective To understand the average concentrations and potential health risks of trichloromethane(CHCl₃)and carbon tetrachloride(CCl₄)in municipal water of supply Beijing after the implementation of South-to-North Water Transfer Project.Methods The monitoring data of CHCl₃ and CCl₄ in treated water,tap water,and secondary water supply were collected in Beijing during 2015—2019.The four-step health risk assessment model recommended by United States Environment Protection Agency(USEPA)was adopted to assess the health risk of them.Results A total of 4292 water samples were collected,the average concentrations of CHCl₃ and CCl₄ were 0.003 mg/L and 0.00062 mg/L,respectively,and the qualified rates were both 100%.The carcinogenic risk values were 3.23×10^-6 for CHCl₃ and 1.51×10^-7 for CCl₄;the non-carcinogenic health risk values were 1.04×10^-2for CHCl₃ and 5.39×10^-4 for CCl₄.Conclusion The health risk of CCl₄ in municipal water supply of Beijing was low,and the health risk of CHCl₃ was within the acceptable range.The South-to-North Water Transfer Project has greatly changed the quality of municipal water supply of Beijing,and still needing to continue the monitoring of water quality and propose risk management measures.