Health Risk Assessment of the Water Environment of Dongting Lake

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 dry season 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.