洞庭湖水环境健康风险评价

Health Risk Assessment of the Water Environment of Dongting Lake

为研究洞庭湖水环境污染对人体健康产生的危害风险，根据2009-2011年洞庭湖水质监测数据，采用美国环境保护署（USEPA）推荐的水环境健康风险评价模型，对洞庭湖通过饮用水途径引起的水环境健康风险进行了评价。结果表明：由毒性物质所致健康危害的个人年总风险在1.37×10-5～3.06×10-5/a之间，平均为1.84×10-5/a，低于美国环境保护署（USEPA）推荐的最大可接受风险水平1×10-4/a。毒性物质总健康风险主要来自As，水环境健康风险表现为东洞庭湖、南洞庭湖＞西洞庭湖的空间分布特征和丰水期＞枯水期＞平水期的水期变化特征。水环境健康风险污染物As主要来源于湘江，因此，加强湘江流域重金属,特别是As的污染治理是降低洞庭湖水环境健康风险的有效途径。

To study the risk of water pollution in Dongting Lake on human health, based on the monitoring data of water quality of Dongting Lake from 2009 to 2011, we assessed the potential health risk of supplying drinking water from Dongting Lake using the model for health risk assessment of water environment recommended by USEPA. Results showed that the total health risk caused by toxic substances to the individual persons per year were 1.37×10-5/a ~ 3.06×10-5/a, with an average of 1.84×10-5/a, less than the maximum acceptable level of 1×10-4/a recommended by USEPA. The total health risk of toxic substances was mainly from As. A spatial pattern of the risk was found larger in East Dongting Lake and South Dongting Lake than in West Dongting Lake, while a temporal pattern of the risk was： rainy season ＆gt; dry season ＆gt;normal season. The water pollutant As was mainly from Xiangjiang River, therefore, a stricter control of heavy metals, particularly As, in Xiangjiang River basin is an effective way to reduce the water environmental health risk of Dongting Lake.