水源水水质风险评价的讨论及实例——以南方N市为例

Discussion on the Risk Assessment of Raw Water quality——Regarding one Southern City as the Case

水质风险评价是环境风险评价的重要组成部分。文章从数据收集以及评估、有毒性评价、暴露评价、风险表征等四个方面,探讨了以长江水为饮用水源水的N市水质健康风险评价体系的构建,并利用相关数据进行分析讨论。结果表明,水源水体中致癌物质六价铬、砷的风险值较高,镉的风险值虽未超标但也已经接近国际标准;非致癌物质氟化物、铅、铁、氨氮、汞、氰化物、锰、挥发酚的非致癌风险都低于国际水平;水源水中11项污染物的危害指数排序为:砷>氟化物>六价铬>铅>镉>铁>氨氮>汞>氰化物>锰>挥发酚,其绝对值大部分都超过了1。

Water quality risk assessment is an important part of environmental risk assessment. Based on 4 aspects of data collection and evaluation,toxic evaluation,exposure to toxic evaluation,risk characterization,this paper discusses the construction of health risk assessment system for water quality of one city which uses the Yangtze River as raw drinking water and analyzes the related data. The results show that cancerogenic substances,hexavalent chromium and arsenic are high risk,cadmium doesn＇t exceed the standard,but close to the international standard; risks of non carcinogens,such as fluoride,lead,iron,ammonia nitrogen,mercury,cyanide,manganese and volatile phenol are lower that of the international level; the order of risk shows： senic fluoride hexavalent chromium lead cadmium iron ammonia nitrogen mercruy cyanide manganese volatile phenol and the absolute value mostly exceeds 1.