Keywords: 
• Cr(Ⅵ) /
• chemical carcinogens /
• the mainstream of Hun river /
• water environment /
• health risk assessment

Abstract: With rapid growth of economic development, more and more pollutants were poured into river and it had exerted negative effects on human health. The conventional water quality assessment could't reflect the risk degree to human health. So the health risk assessment was essential. Based on the water quality monitoring data about the eleven monitoring indexes in surface water during 2009-2010, this paper assessed the environmental health risk through drinking water with the model for USEPA water environmental health risk analysis in the mainstream of Hun River. The results showed that the concentrations of heavy metals and CN-were lower than National Grade l]I (GB3838-2002), and the concentrations of NH₄⁺-N and volatile hydroxy-benzene exceeded the maximum permissible limits of National Grade llI. The health risk of NH₄⁺-N was the greatest in non-carcinogens. But compared with the health risk of carcinogens, the health risk of non-carcinogens was negligible. The greatest health risk for individual person per year was caused by Cr(VI), and it were higher than the standard value recommended by International Commission on Radiological Protection (ICRP). The total health risk in Hun River was the smallest in wet season, and the biggest in normal water season. The health risk in Hun River decreased from the upstream to downstream, but the health risk exceed the standard value in every sampling sites. Cr(VI) was the main risk factors in Hun River. So an effective way to reduce and control the discharge of Cr(VI) must be carried out to decrease the environmental health risk, and the management of wastewater in agricultural non-point source and industry must been strengthened.