淠河灌区集中式饮用水源地水质健康风险等级研究

The health risk level of water quality in the centralized drinking water sources of the River Pihe irrigation district

为了解淠河灌区集中式饮用水源地水质健康风险状况，选取Cr6＋、As、Cd、Pb、Mn、Cu、Zn、Fe、F、NH4＋-N等10项污染因子作为健康风险指标，运用三角模糊集理论和α-截集技术，确立置信度为0.8，得到各污染指标的健康风险区间值；同时建立模糊化特征的风险等级判别标准和判别方法.结果表明，该水源地水质总健康风险值为4，风险等级为Ⅳ级（一般）.3种化学致癌物Cr6＋、As、Cd合计风险区间值介于5.58610-5-9.36510-5之间，风险由高到低的顺序依次为：Cr6＋〉As〉Cd，浓度在空间上变化不大，具有一定的负面效应，但均未超过美国环保署推荐的最大可接受水平1.010-4；Cr6＋风险区间值较大，风险等级较高，应将Cr6＋作为首要的健康风险管理控制指标. 其余7种非致癌化学有毒物没有风险，不存在负面效应，非致癌健康风险明显低于致癌风险.

The health risk level of water quality in the centralized drinking water sources of the river Pihe irrigation district was studied by selecting the pollutants of Cr6＋, As, Cd, Pb, Mn, Cu, Zn, Fe, F and NH4＋-N. The interval values of the health risk of each indicator for confidence degrees of 0.8 were identified based on the triangular fuzzy mathematics theory and α_cut set technique. In addition, a new classification model characterized by an assessment criterion of seven-graded health risk based on the fuzzy set theory was developed. The results indicate that the gross value of health risk is four with the risk level of Ⅳ in this district. The risk values of three chemical carcinogens range from 5.58610-5 to 9.36510-5 and are in the order Cr6＋〉As〉Cd. With little spatial variation, the risk level has some negative effects, but lower than the maximum allowance level recommended by U.S.EPA （1.010-4 a-1）. Cr6＋ is considered the primary polluting factor due to its higher interval values, and controlling the emissions of the waste water containing Cr6＋ should be prioritized in prevention and management. The seven non-carcinogens are risk-free and have no negative effect, thus their non-carcinogenic risks are significantly lower than the health risks caused by the carcinogens in the drinking water.