基于健康风险的水源地水质安全评价

将健康风险评价引入水源地水质安全评价中,以致癌风险和危害指数分别反映源水中污染物对人体致癌危害与非致癌慢性毒害的程度.选取我国华东一重要城市的最大水源地进行分析,结果表明,该水源中12种致癌物质总致癌风险为4.76×10-5,其中砷是最主要的致癌污染物,致癌风险为4.00×10-5;24种污染物总危害指数为0.906,其中位列第一、第二位的是氟化物和砷,其危害指数分别为0.393和0.207;不同类型污染物健康风险的分析对比表明,无机污染物是最主要的风险贡献源,应予以重点监控;汛期与非汛期健康风险的对比表明,汛期应为水质重点监控时段,同时应重视面源污染的治理.

Water source quality safety evaluation based on health risk assessment

The health risk assessment is introduced to assess the quality of water source provided for city, the cancer risk and hazard index are used to characterize the carcinogenic potential and chronic toxicity hazard of contaminants respectively. This method is applied to assess the quality of drinking water providing to an important city in east of China. The analysis shows that the arsenic is the major carcinogenic substance with cancer risk 4.0×10-5, and the cumulative cancer risk caused by 12 kinds of carcinogenic substances is 4.76×10-5. The total hazard index caused by 24 kinds of contaminants is 0.906, in which the hazard index of fluoride is 0.393 and that of arsenic is 0.207. The comparison of health risk for different kinds of contaminant indicates that the non organic contaminant is the major source of risk contributor which must be emphatically monitored. Furthermore, the comparison of risks in flood season with that in dry season reveals that more attention must be paid to flood season and at the same time the management of non point pollutant should be emphasized.