The Detection And Health Risk Assessment Of Drinking Water In Guiyang City

In order to know the water quality of domestic drinking water in Guiyang, 72 kinds of water quality indexes of 12 sampling site from the terminal tap water of Guiyang Western Suburbs Water Plantin were collected and analyzed in different water period of 2013-2014, such as dry season of March, wet season of July and normal season of December. The potential risk of 13 kinds of heavy metals and 16 kinds of polycyclic aromatic hydrocarbons to human health was assessed by the model which is recommended by the U.S. environmental protection agency(USEPA), which based on the Chinese population exposure parameters published in December 2013. The drinking water and health risk assessment under different consumption habits in Guiyang were also researched.Research shows that:(1) The 72 kinds of drinking water indexes of Guiyang all according with the national drinking water health standards "GB5749-2006". According to the reason of precipitation and productive consumption, the concentrations of Hg, Se, Mo and F were the max valuein March. The concentrations of Pb, Fe, Cu, Ni, benzo [a] pyrene and fluoranthene presented the max valuein July. And the concentration of Mn was the max valuein December.(2) Based on the health risk assessment of Chinese population exposure parameters, the results of 13 kinds of the health risks of heavy metals and 16 kinds of polycyclic aromatic hydrocarbons value did not exceed the maximum acceptable level and threat to the health of residents in Guiyang. Average total cancer risk of adult was 3.4 times as that of children, but the non-cancer risk of average of them were relatively close. The risk of cancer was greater than that of non-cancer. The value of health risks through the mouth exposed way was significantly greater than that though skin exposed healthy. It indicated that the mouth exposed way was the primary exposure route.(3) It indicated that the health risks of molybdenum was the highest than all the carcinogenic heavy metals. The order of the carcinogenic heavy metals average risk value was Mo>Cu>Mn>Ba>Se>Zn>Pb>Ni>Hg>Ag. The total risk of cancer and non-cancer of heavy metals were the biggest in December, and the risk value of PAHs though mouth exposed way was the highest in July.(4) Based on the different exposure parameters such as American and Chinese, health risk value were different, but also the different assessment results was induced between children and adults.(5) The research of drinking water consumption habits in Guiyang suggested the different ways of consumption such as heating and filtration were the effectively impact on water quality index. Retention of water and the dis-retention of water quality has certain difference. The spending time was almost no effect on the water quality of drinking water. Health risk evaluation results showed that the risk of cancer and non-cancer of drinking water under different consumption habits, which through the mouth exposed, did not exceed the maximum acceptable level, and it did no threat to the health of residents in Guiyang.