| In China both water pollution and waste problems are very serious. Wastewater treatment and reuse is an effective measure to solve them. Recent years, the wastewater reuse has become the studying key in the world. With increasing quantity of wastewater reuse, the dangers which would cause by reclaimed water become more and more important. So it is important to study the influence of the reclaimed water on human health and the environment using the method of risk assessment.This paper monitored and analyzed the concentration of the usual chemical pollutants, microbial pathogens and Endocrine Disrupting Chemicals in the effluent water from secondary settling tanks of oxidation ditch process of Handan East Wastewater Treatment Plant and that in the reclaimed water by MCM, MCM-UF, MCM-NF and MCM-RO treatment techniques. The monitoring data were analyzed with nonparametric hypothesis testing method and it was found that the concentration of all pollutants fit with lognormal distribution well. Thus, the lognomal distribution was used in this study as the statistical model for the pollutants concentration and variability in reclaimed water.Referring difference wastewater reuse standard, the probability of the reclamation water by wastewater reuse technical process meets the quality standards was calculated, The usual chemical pollutants in secondary effluent and the effulent water of MCM was safty for irrigation (Irrigation of public access areas, parks, etc), industry and agricultural irrigation, while they presented high risk to human health and ecological environment for recreational impoundment (swimming, full body contact) and groundwater recharge. The usual chemical pollutants in MCM-UF are safty for irrigation (Irrigation of public access areas, parks, etc), industry, agricultural irrigation and groundwater recharge. The microbial pathogens in secondary effluent and the effulent water of MCM and MCM-UF presented high risk to human health. The usual chemical pollutants and the microbial pathogens in MCM-NF and MCM-RO is safty for irrigation (Irrigation of public access areas, parks, etc), industry, agricultural irrigation, groundwater recharge and recreational impoundment.Three common reuse applications-landscape irrigation (Irrigation of public access areas, parks, etc), agricultural irrigation, and recreational impoundment (swimming, full body contact) were taken into consideration for evaluation of the health risks. The exposure pathways include inhalation of aerosols, ingestion of water or food, absorption through the skin via dermal contact. For landscape irrigation, the exposure was estimated as 1mL per day for 104 days; for agricultural irrigation, the exposure was judged as10mL on each of the 365 days in a year; and for recreational impoundment, a swimmer was exposed to 100mL of reclaimed water on each of 40 days during summer season.The noncarcinogenic risk of DEP and DHP was calculated and analyzed. The results show noncarcinogenic annual risk for the three reuse applications was distributed in the range of 10-13/a. to 10-11/a.and which was much lower than the recognized neglectable risk level 10-7～10-8/a.The simulation results show that health risks caused by DEP and DHP in reclaimed water are acceptable or negligible.
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