Bayram Hashemzadeh - Department of Environmental Health, Khoy School of Medical Sciences, Khoy, Iran
Sahar Geravandi - Razi Educational Hospital, Clinical Research Development Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz,Iran
Mohammad Javad Mohammadi - Abadan School of Medical Sciences, Abadan, Iran- Student Research Committee, Department of Environmental Health Engineering, School of Health and Environmental Technologies Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Ahmad Reza Yari - Research Center for Environmental Pollutants, Qom University of Medical Sciences, Qom, Iran

Background & Aims of the Study: The most important compounds in hospital wastewater areantibiotics, disinfectants, anesthetics, radioactive elements, static cytotoxic agents, otherchemicals and hazardous materials that caused to be different domestic sewage. The purpose ofthis study was the evaluation of performance of extended aeration biological system in pollutantsremoval from Razi Hospital wastewater treatment plant (WTP), Ahvaz city of Iran.Materials and Methods: The hospital wastewater disposal and treatment in Razi hospital havebeen studied in this cross-sectional research. Total of 12 samples from effluents of wastewatertreatment plants were collected and tested for pH, Biological Oxygen Demand (BOD5),Chemical Oxygen Demand (COD), Total Suspended Solid (TSS) and Total Coliform (TC). EPAstandard method was used for conducted trials. Finally, the relationship between results atdifferent months and stations was done, using SPSS18 and descriptive statistics.Results: Results shown that parameters average in effluent was pH=7.46 ،BOD= 48.58 mg/l,COD=99.25 mg/l, TSS=54 mg/l, NH3=5.65mg/l, Turbidity=29.57 NTU. Also total coliform andfecal coliform of effluent were 46.19 MPN/100 ml and 36.65 MPN/100 ml, respectively.According to results, the percentage of BOD, COD, TSS and TC removal in WTP were 85.21,82.46, 86 and 90.15.Conclusion: Based on these findings, Razi hospital effluent wastewater treatment plant wasmitted at Iran environmental standards for discharge to recipient wasters. Based on the result ofour study, Extended Aeration Biological System is a comparatively suitable process for BOD,COD, TSS and TC removal from hospital wastewater.

Wastewater treatmentHospital wastewaterExtended aerationOrganic matterPollutantsAhvazIran