Korean Water Quality Standards for the Protection of Human Health and Aquatic Life

The Korean water quality standards (WQS) for the protection of human health have recently been expanded. The main reason for the expansion was to address the concern of increasing hazardous pollutants in water environments. A risk-based approach was used to derive the WQS for eight toxic substances including antimony, benzene, carbon tetrachloride, chloroform 1,2-dichloroethane, dichlromethane, diethylhexylphtalate, and tetrachloroethylene. Same methodology has been applied to revise the existing substances, and the WQS for lead and cadmium were reinforced. The method for deriving water quality criteria was revised from the US EPA's equation for deriving ambient water quality criteria. The Korean standard values were used for the input parameters where possible. The water quality monitoring data from four major rivers in Korea were used as an exposure data. Priority chemicals for the consideration of WQS expansion were determined based on the human health risk assessment. Subsequent to the current WQS, Korean ministry of environment plans to expand WQS up to thirty substances by the Year 2015. Ecological risk criteria were also derived and they will be incorporated in the WQC in the near future. This work was conducted as a part of the project entitled 'Development of integrated methodology for evaluation of water environment'.