Study On The Application Of Disability Adjusted Life Year In Health Risk Assessments Of Wastewater Reuses

Faced with the double pressure of the shortage of water resources and seriouswater pollution,urban wastewater reuses becomes the effective way to solve theproblems. So more and more attention are paid to the poisonous and harmful materialsof the recycle process to risk of human health. At present, the stochastic simulationmethod (for example using Monte-Carlo method) to calculate the distribution of thehealth risks is applied in health risk assessment of urban sewage reuse, in order to getthe disease probability of different pollution factors.But the probability of disease can’treflect the degree of disability and the length of time, at same time it can’t reflect deathto the influence of the productive forces which caused by the disease.Using the disability adjusted life year (DALY) as a new index of disease’squantitative burden, when the World bank and the World health organization, Harvardschool of public health were making study of the global burden of disease. DALY takeninto account both the burden of disease caused by death and disability,using year as unit,compared the fatal with nonfatal health outcomes which was more seriously in the samescales.This paper used DALY in sewage recycle regeneration to the risk assessment ofhuman health, researched the methods of DALY in sewage reuse regeneration of theapplication of health risk assessment, and used the city sewage recycle regeneration ofXi’an as a case to study wastewater reuse to the risk of human health, finally made theindexes of disease’s burden quantitative. After analyzing the risk assessment of human health caused by the city sewagerecycle regeneration of Xi’an, the method of health risk assessment which DALY usedin sewage renewable was established. Comparing and analyzing several main pollutionfactors of renewable water of Xi’an which caused disease burden to the human body,knowing that rotavirus and hepatitis a virus of pathogenic microorganisms and the Cd ofcarcinogenic chemicals were the may pollutants which caused disease burden. It couldlead to disease burden were0.86DALY/ten thousand,0.38DALY/ten thousand,1.58DALY/ten thousand people seriously, comparing with other disease burdens that sewagereuse to human health was smaller.