1.Assessment on health risk of drinking water in Hangzhou
Ming XUE ; Quan JING ; Liqun ZHANG ; Xiaofang WANG ; Zhongqiao YANG ; Tianbin BIAN ; Like GONG
Journal of Preventive Medicine 2019;31(1):28-32
Objective:
To assess the health risk associated with drinking water in Hangzhou from 2016 to 2017,and to provide evidence for the safety of drinking water .
Methods:
The monitoring data of 5 genetic toxic substances(arsenic,hexavalent chromium,cadmium,chloroform,tetrachloromethane)and 13 body toxic substances(lead,mercury,selenium,cyanide,fluoride,nitrate,iron,ammonia nitrogen,manganese,copper,zinc,aluminum,volatile phenol)from 36 source water samples,36 finished water samples and 288 tap water samples in the main urban areas of Hangzhou were collected from 2016 to 2017. The health risk of drinking water containing the chemical pollutants mentioned above were assessed based on the evaluation models recommended by United States Environmental Protection Agency .
Results:
The concentrations of 5 genetic toxic substances and 13 body toxic substances in source water,finished water and tap water were all within the reference limits issued by Standards for Drinking Water Quality(GB 5749—2006). The carcinogenic risk,non-carcinogenic risk and total health risk caused by the chemical pollutants in the source water were 2.18×10-5/a,7.75×10-9/a and 2.18×10-5/a. The carcinogenic risk,non-carcinogenic risk and the total health risk caused by the chemical pollutants in the finished water were 1.08×10-5/a,3.70×10-9/a and 1.08×10-5/a. The carcinogenic risk,non-carcinogenic risk and total health risk caused by the chemical pollutants in the tap water were 1.96×10-5/a,3.61×10-9/a and 1.96×10-5/a. The carcinogenic risk and total health risk caused by chemical pollutants ranged from high to low in the source water,tap water and finished water. The non-carcinogenic risks ranged from high to low in the source water,finished water and tap water .
Conclusion
The health risks of 18 chemical pollutants in drinking water in Hangzhou were at a low level,with the greater carcinogenic risk than the non-carcinogenic risk. Hexavalent chromium had the highest carcinogenic risk,while fluoride and aluminum had the highest non-carcinogenic risk.