Water Environmental Health Risk Assessment Of Dalian

This current study has assessed the health risks caused by drinking water inDalian city in the last five years. The assessment was based on the four steps ofenvironmental health risk assessment by American Academy and methods by theAmerican Environmental Protection Agency, and established a health risk assessmentsystem. Hazard identification, exposure assessment and risk assessment of chemicalsubstances in water are made according to the monitoring data of water quality.Meanwhile, dangers are analyzed on the condition that how and why people atdifferent ages are affected by the same water. Referring to the maximum acceptablelimit recommended by the International Radiation Commission, the followingconclusions are made.(1) In the water body of the region in question, arsenic and Cr+6are the largerhazards among chemical carcinogens, the risk for carcinogenic effects are more thanthe maximum acceptable value of5.0×10-5a-1recommended by InternationalRadiation Commission; the minimum risk for Carcinogenic effect is cadmium, it doesnot exceed the standard value for five consecutive years. Among non-carcinogens,nnly fluoride exceeded the standard value of the health risks for five consecutiveyears.Mercury exceeded the standard value of the health risks in2008. Lead andcopper exceed the maximum acceptable level for children in some years. Phenol isone of the non–carcinogens, which causes the smallest danger. The danger caused bycarcinogen is greater than that of the non-carcinogens.(2) Among three groups of people, children, male adults and female adults, whoare exposed to the water, children stand more danger than adults, while female adultsstand more danger than male adults.(3) Drinking water and skin contact are the two routes of exposure. Comparedwith each other, drinking water causes more danger. Especially the risk of carcinogens,arsenic and hexavalent chromium exceeds the maximum acceptable level throughdrinking water. The risk of skin exposure is much smaller.In conclusion, in the water treatment process, arsenic and Cr+6should be dealtwith first. As for non-carcinogens, fluoride should be put in the first place. Chemicalsin water cause much more damage to children than adults, so children need to pay more attention.