基于模糊化的长株潭地区地下水重金属健康风险评价

健康风险评价是表征环境污染物对人体健康危害程度(或致死)的一种风险评价方法. 主要研究了长沙、株洲和湘潭三市地下水由于重金属污染而造成的人体健康风险. 采用模糊化原理将评价标准分为6个等级,即低风险、低～中风险、中风险、中～高风险、高风险以及极高风险,可直观地反映地下水中重金属所致健康危害的风险水平. 结果表明:2002-2006年长沙、株洲和湘潭三市地下水重金属所致健康风险水平较高;致癌重金属比非致癌重金属所致个人年均风险值大,其所致健康危害的风险大小依次为Cr 6+＞As＞Cd;在重金属所致健康危害的总风险水平中,2002-2006年长沙的个人年均风险值处于逐年降低的趋势,而湘潭和株洲的个人年均风险值都出现了先增高后降低的趋势,这可能是由于近年来长株潭地区加强了地下水的监测与污染防治工作所致.

Health Risk Assessment from Heavy Metals in Groundwater of Changsha-Zhuzhou-Xiangtan District Based on Fuzzy Theory

Health risk assessment is a method of risk assessment to represent the degree of health harm (or death) to people caused by environmental contamination. The health risks from heavy metals in the groundwater of Changsha, Zhuzhou and Xiangtan Cities in Hunan Province were investigated. Fuzzy theory was adopted to establish the risk assessment system, in which the risks were classified according to the six levels "low", "low-medium", "medium", "medium-high", "high" and "very-high". Compared with previous research, the system adopted in this study can represent the levels of health risk of heavy metals more directly. The results showed that the groundwater health risk level of heavy metals in Changsha, Zhuzhou and Xiangtan Cities was quite high. The health risk caused by carcinogenic heavy metals was far higher than that caused by non-carcinogenic heavy metals, and the sequence of each carcinogenic heavy metal was Cr~(6+)＞As＞Cd. The health risk of heavy metals in the groundwater of Changsha decreased from 2002 to 2006, while the health risk of heavy metals in the groundwater of Zhuzhou and Xiangtan increased first and then decreased from 2002 to 2006, as the water quality monitoring and groundwater pollution prevention programs were strengthened in Changsha, Zhuzhou and Xiangtan.