Journal of Environmental Health and Sustainable Development

en Evaluating the Efficiency of Aerated Lagoon System regarding the Removal of Indicator Bacteria from Municipal Wastewater Water quality and wastewater treatment and reuse Original articles <div style="text-align: justify;">Introduction: Treatment of municipal wastewater is essential to remove bacteria. This study is designed to evaluate the efficacy of a wastewater treatment plant (WWTP) for the removal of bacteria and using for irrigation or discharge in the Caspian Sea according to the World Health Organization (WHO) regulations. Materials and Methods: A total of 105 samples were collected from 7 stations, including the inlet and the outlet of the WWTP in Bandargaz City (Iran), the intersection point of wastewater effluent with Caspian Sea (Gorgan Bay), and a radius of <st1:metricconverter productid="200 meters" w:st="on">200 meters</st1:metricconverter> in three directions east, west, and north of the intersection point of wastewater in Gorgan Bay. The multiple-tube fermentation technique was used to enumerate bacteria, and results were expressed as the Most Probable Number (MPN) per 100 ml. Results: Bacteriological analysis exhibited that the concentration of total coliform, fecal coliform, fecal streptococci, and Clostridium perfringens were 1.38 ×1010, 5.57 × 107, 5.53 × 109, 1.26 × 109 in inlet, and 1.38 × 1010 , 5.57 × 107, 5.53 × 109 , 1.26 × 109 in outlet of WWTP, respectively. Conclusion: The aeration lagoon has a low performance in bacteria population removal, which may be due to the climate condition of this region (few sunny days and many cloudy and rainy days). This effluent was not generally acceptable for discharge in the environment and reuse. Therefore, it is essential to modify the disinfection process to keep the concentration of bacteria under control. Additionally, continuous monitoring is necessary to control the quality of wastewater  before discharge into the environment or reuse. </div> Environmental monitoring, Bacteria, Wastewater, Seawater, Caspian Sea 2378 2387 http://jehsd.ssu.ac.ir/browse.php?a_code=A-10-118-5&slc_lang=en&sid=1 Sara Salar pargol.salar@gmail.com 0000-0002-2643-8305 No Student Research Committee, Faculty of Health, Golestan University of Medical Sciences, Gorgan, Iran Fatimah Eftekhari f.eftekhari1375@gmail.com 0000-0002-9930-4391 No Student Research Committee, Faculty of Health, Golestan University of Medical Sciences, Gorgan, Iran Maryam Shafipour Maryam.shafipour@gmail.com 0000-0002-8637-2280 No Department of Environmental Health Engineering, Faculty of Health, Golestan University of medical science, Gorgan, Iran Reza Ebrahimnia rsf57ko@gmail.com 0000-0001-8913-4467 No Department of Environmental Health Engineering, Faculty of Health, Golestan University of medical science, Gorgan, Iran Ebrahim Moghadar Al.shahryar@gmail.com 0000-0001-9538-2854 No Bandargaz, Health office, Golestan University of Medical Sciences, Bandargaz, Iran Seyed Abedin Moosavi seyedabedin.moosavi.49@gmail.com 0000-0002-6879-8958 No Bandargaz, Health office, Golestan University of Medical Sciences, Bandargaz, Iran Hassan Safari safari@goums.ac.ir 0000-0002-4541-6478 No Department of Environmental Health Engineering, Faculty of Health, Golestan University of medical science, Gorgan, Iran Navisa Sadat Seyedghasemi seyedghasemi_n@yahoo.com 0000-0001-9206-6311 No Department of Biostatistics and Epidemiology, Faculty of Health, Golestan University of Medical Sciences, Gorgan, Iran. Ali Shahryari Dr.shahryari@goums.ac.ir 0000-0002-5495-7372 Yes Department of Environmental Health Engineering, Faculty of Health, Golestan University of medical science, Gorgan, Iran