IJEP 41(9): 1041-1045 : Vol. 41 Issue. 9 (September 2021)
Sreedevi Sarsan*, G.R. Ksheeraja, Manne Supriya, S. Dedeepya Maha Lakshmi and D. Anusha
St. Pious X Degree and P.G. College, Department of Microbiology, Hyderabad, Telangana, India
Abstract
Water pollution has become a perennial concern all over the world especially in developing countries due to rapid urbanization and increased industrialization. This polluted water is of great concern which impacts our social life, health and environment. There are various conventional wastewater treatment methods available, like activated sludge, trickling filters, slow sand filtration, UV radiation, etc., but they have certain limitations, like expensive equipment requirement, skilful manpower requirement and formation of carcinogenic bypro-ducts. Constructed wetlands are effective and environmental friendly ecosystems that are applicable for the reduction of pathogens from wastewater apart from the removal of chemical pollutants. There are many types of pathogens found in wastewaters that originate from human and animal activities. It is practically impossible to identify all the microbial species present in a wastewater sample due to technical difficulties, complexity and expense. Also, due to the complexity of pathogen removal mechanisms and various influencing factors, the knowledge on the fate and removal of bacteria in constructed wetlands (CWs) is still not sufficient. The main objective of our study was to test the efficiency of constructed wetlands in the reduction of pathogens from wastewater. The inlet and outlet water samples were collected from the constructed wetlands, serially diluted and spread plated on specific media plates. The colonies obtained were identified as well as enumerated using viable count technique and percentage reduction in pathogens was determined. The results showed that there is a 60-80% reduction in the number of different bacterial pathogens in the wastewater samples treated by Cw systems.
Keywords
Wastewater treatment, Constructed wetlands, Pathogenic microorganisms, Bacteria isolation
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