Ecological Risk Assessment of Three Chlorophenols in the Main Rivers in China

Chlorophenol chemicals are one kind of the priority pollutants widely distributed in the waters of China.The ecological risks of a mixture of three chlorophenols(pentachlorophenol,2,4-dichlorophenol and 2,4,6-trichlorophenol) in the main rivers in China were assessed by deriving the risk quotient for mixtures(RQm) of chemicals with a similar mode of action.The RQm values of the chlorophenol mixtures in all the rivers were lower than 1.The value was the highest(0.377) in the Yellow River,while the values in the Yangtze,Huaihe,Haihe and Songhua Rivers were 0.055,0.039,0.035 and 0.010,respectively.The values of RQm in the other rivers in China were lower than 0.010.In general,the mixed ecological risks of the three chlorophenols to aquatic organisms were higher in the Northern rivers than in the Southern rivers in China.