Water Environmental Health Risk Assessment For The Drinking Water Source Of Xinyang City

China’s current water pollution situation is relatively serious,the safety of drinking water sources has a certain threat and residents of drinking water safety issues is a major concern.The domestic water of Xinyang city is from Nanwan Reservoir which is the only source of drinking water,the reservoir water environment due to the destruction caused when drinking water health hazard has occurred,the evaluation of drinking water sources on water quality standards for managers does not directly reflect the relationship with human health.Water environmental health risk assessment as a new environmental assessment method,the difference in previous risk assessment only focus on chemical pollutants concentration was improved,it is expressed on its degree evaluation index,the water environment pollutants and human health link,a quantitative description of the water of various pollutants to human health risks.This paper for 2010 to 2014 Xinyang City drinking water source of the water environment of health risk assessment,proposed by the American Academy of health risk evaluation of four-step and the United States Environmental Protection Agency proposed health risk evaluation two methods based on the theory,a healthy risk evaluation system.According to the water quality monitoring data of drinking water in ammonia,fluoride,cyanide,copper,zinc,mercury,arsenic and hexavalent chromium eight kinds of pollutants hazard identification,exposure assessment and risk evaluation.Analysis and comparison of different exposure groups to health hazards in the community drinking water,and routes of exposure cause the skin to the International Commission Radiological Protection（ICRP）recommended maximum acceptable limits as the reference standard,the evaluation results were analyzed.The main research results are as follows:From 2010 to 2014 eight kinds of pollutants in Xinyang city drinking water source of drinking water by way of personal health risk,non cancer risk caused by three kinds of exposure groups were in the order of magnitude of 10^-8,the maximum value of fluoride risk,more than the International Commission on Radiological Protection（ICRP）recommended maximum the acceptable limit of 1.0×10^-9a^-1,the non carcinogenic risk values were lower than the maximum acceptable limits,carcinogenic health risks from larger arsenic for children in 2010 has exceeded the ICRP recommended maximum acceptable limits of 5.0×10^-5a^-1 and six chromium for adults and children the value of risk were lower than the maximum acceptable limit.From 2010 to 2014 Xinyang City drinking water source water 8 pollutants through skin to skin contact caused by way of personal health risk in non carcinogenic substance is still the value of risk of fluoride,fluoride risk of adult females and children values were more than recommended by the ICRP maximum acceptable limit of 1.0×10^-9 a^-1 and carcinogenic substance arsenic and chromium（Ⅵ）caused by exposure group health harm personal annual risk values are very low,value at risk and ICRP recommended maximum limit value of 6 or 7 orders of magnitude lower,it does not do harm to human health.Carcinogenic substances in drinking water pathways accounted for a greater health risk,compared to non carcinogenic substances greater harm;and for the skin exposure to non carcinogenic substances under the value of the risk of more weight,compared to the carcinogenic substance.Combined with the two exposure ways of health risk value found that risk trend of the overall trend of health risk value and the way of drinking water and skin contact way is basically the same,from 2011 showed the trend of decreasing year by year.According to the analysis of the health risk assessment results of three kinds of exposure groups,we found that the risk value of children is much greater than the value of adult and the value of adult women is greater than adult men.Comprehensive analysis,the water quality management of drinking water source in Xinyang City,priority should focus on carcinogens arsenic.It is carcinogenic risk in drinking water sources of the main factors,and the non carcinogenic risk of fluoride in material were more than recommended by the ICRP maximum acceptable limits,compared to other non-carcinogenic substances should be given priority attention.But overall,the water quality of drinking water source in Xinyang city is good.