Risk assessment of Arsenic in geothermal water from Tangchi, China

摘要

On the basis of health risk assessment methods of contaminated sites recommended by the U.S. Environmental Protection Agency, human health risks due to arsenic in geothermal water of Yunnan Tangchi have been evaluated by combining the speciation of arsenic. The results have shown that total arsenic level in the geothermal water is 0.1655mg·L~(-1), in which As~(3+) and As~(5+) account for 64% and 36% respectively. Arsenic total non-carcinogenic risk index is 75.73; total carcinogenic risk is 1.10×10~(-2), which can lead to strong non-carcinogenic and carcinogenic hazards to human health. Drinking way is the most important route of exposure to risk, which account for more than 90% of the hazards. The health risk of As~(3+) approximately is 107 times that of As~(5+), accounting for 99.1% of the total risk. The speciation have greatly affected the health risks of arsenic. There are some uncertainties in the calculated result in this study, but it can be used for reference in the study of the health risk assessment consisted of the speciation of pollutants.