湘江湘潭段水环境主要污染物的健康风险评价

依据2001—2005年的水质监测资料，应用健康风险评价模型，对湘江湘潭段水环境主要污染物进行了健康风险评价. 结果表明:在所监测的指标中，pH，ρ(Cr6+)，ρ(Cu)和ρ(Zn)等未超标(GB3838-2002)；ρ(DO)，ρ(Pb)，ρ(CN)，ρ(COD_Mn)和ρ(BOD₅)等偶尔超标；ρ(Hg)，ρ(Cd)，ρ(As)，ρ(挥发酚)，ρ(NH₃-N)和粪(总)大肠菌群等经常超标. 历年来化学致癌物As的个人年风险值均高于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平，而Cd和Cr6+的个人年风险值均低于最大可接受风险水平. 非致癌物的个人年风险顺序为Pb>NH₃-N>Hg>CN>挥发酚，这5种污染物的健康危害年风险值均低于国际辐射防护委员会(ICRP)推荐的最大可接受风险水平. 污染物健康风险比较表明，化学致癌物对人体健康的风险值远超过非致癌物的危害，应作为风险决策管理的重点对象. 

Health Risk Assessment of Main Water Pollutants of Xiangjiang River in Xiangtan City

Based on the local water quality monitoring data from 2001 to 2005, the health risks of some water pollutants from Xiangjiang River in Xiangtan City was assessed. The results showed that the concentrations of pH, Cr⁶⁺, Cu and Zn were lower than those set by the national standard for surface water (GB3838-2002), however, the concentrations of Hg, Cd, As, NH₃-N, hydroxybenzenes, and fecal coliform group exceeded the maximum permissible limits in surface water. Thehealth risks of As to the individual person per year in terms of chemical carcinogens of Xiangjiang River in Xiangtan City were higher than the standard value recommended by International Commission on Radiological Protection (ICRP). The health risk of Cd and Cr⁶⁺ to the individual person per year were lower than those of standard values. The health risk to the individual person per year interms of non-carcinogens followed: Pb > NH₃-N > Hg > CN > hydroxybenzenes, and their risk values were lower than those recommended values. The health risks of chemical carcinogens were much higher than those of non-carcinogens. Therefore, it is an effective way to reduce the discharge of chemical carcinogens such as As and Cd into the Xiangjiang River to decrease the environmental health risk.