World Journal of Advanced Research and Reviews, 2020, 07(01), 111–116 World Journal of Advanced Research and Reviews e-ISSN: 2581-9615, Cross Ref DOI: 10.30574/wjarr Journal homepage: https://www.wjarr.com  Corresponding author: Nwakanma C, Email: Copyright © 2020 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. (R ESEARCH A RTICLE ) Toxicological examination of microbial isolate from sites located in freshwater ecosystem at Ugwuomu-nike, Enugu State Nwakanma C 1, * , Unachukwu MN 2 and Okoli CC 2 1 Department of Environmental Management and Toxicology, Michael Okpara University of Agriculture, Umudike, Abia State. 2 Department of Biological Sciences, Godfrey Okoye University, Enugu State. Publication history: Received on 06 June 2020; revised on 10 July 2020; accepted on 12 July 2020 Article DOI: https://doi.org/10.30574/wjarr.2020.7.1.0190 Abstract The isolation and identification of bacteria associated with influx from human residues located in freshwater ecosystem at Ugwuomu-nike in Enugu State was examined in this study. About eight (8) water samples were collected, four (4) from the lake and the other four (4) from the river close to the residual points. The samples were physiochemically examined for Temperature, pH, Turbidity and Conductivity. Samples were centrifuged and viewed under the microscope for any presence of parasites to be identified. Water culture was carried out using lactose broth to check for possible acid and gas production by the test organisms, and further cultured into eosin methylene blue agar and macConkey agar incubated at 37 o C for 24-48 hours. The isolates were finally cultured on nutrient agar and stored in a stock culture bottles for further analyses. Biochemical testing was also carried out. The microorganisms isolated and identified were Proteus spp, Esherichia coli, Bacillus spp, Staphylococcus aureus, Legionella spp, Enterobacterspp and Micrococcus spp. The Bacillus spp (rod shaped), Staphylococcus aureus (cocci in clusters) and Micrococcus spp (cocci in pairs) turned to be gram positive and non-motile, having Bacillus spp a spore former and the other two species a non- spore formers. Proteus spp, Esherichia coli, Enterobacter spp and Legionella spp as gram negative, non-spore formers and motile microorganisms. Results showed that E.coli isolated was the most frequent organisms and when compared to the remaining microbial isolates after the biochemical analysis, E-coli isolates produced its result as indole positive, oxidase negative, catalase positive, citrate negative, urease negative, coagulase negative. However, when tested on glucose, lactose, and galactose, it produced acid and gas. This study confirms the presences of bacteria at the freshwater ecosystem because of human residues, hence the need for water treatment should be employed to avoid water borne diseases by contact and possible consumption by citizens in that surroundings. Keywords: Toxicity; Micro-organisms; Wastewater; Water analysis; Freshwater ecosystem 1. Introduction Water is an essential resource for life. Water bodies such as streams, rivers, and lakes, are used by humans for multipurpose most importantly for human domestic purposes. An adequate, safe, and accessible supply must be available to all. Improving access to safe drinking water can result in significant benefits to health. Every effort should be made to achieve drinking water with good qualities as safe as possible [1]. Many people struggle to obtain access to safe water. A clean and treated water supply to each house may be the norm in Europe and North America, but in developing countries, like Nigeria access to both clean water and sanitation are not the rule, and waterborne infections are common. Two and a half billion people have no access to improved sanitation, and more than 1.5 million children die each year from diarrheal diseases [2]. According to the WHO, the mortality of water associated diseases exceeds 5 million people per year. From these, more that 50% are microbial intestinal infections, with cholera standing out in the first place. When water becomes contaminated by microorganisms such as bacteria, parasite, viruses, protozoa and so