ABSTRACT

This study is about the microbial risk assessment of different borehole water samples from primary schools within Ugbowo. Four different samples of borehole water used as a drinking source for pupils were collected from different Primary Schools (school A, School B, School C and School D) and the total coliform count using the MPN method were tested also the physicochemical parameters of the samples were also tested. The physicochemical parameters analyzed were all below WHO standard these parameters includes; pH, temperature, turbidity,  salinity, electrical conductivity, suspended particles, turbidity, nitrate, phosphate, sulphate, dissolved oxygen (DO),  biological oxygen demand (BOD), chemical oxygen demand (COD), lead, cadmium, zinc and chromium. These water samples were also analyzed for the presence of micro-organisms, total coliform counts using a MacConkey broth. The MPN coliform index per 100 ml of water samples ranged from 23 to 540 the results also showed the presence of fecal coliform as the organism Escherichia coli which is an indicator organism was present in all samples. Bacteria isolate such as Proteus vulgaris, Enterobacter aerogenes, Bacillus subtilis, Klebsiella oxytoca and Morgenella spp. were also isolated from the water samples. Most of these organisms are Gram negative microorganisms and are usually associated with gastrointestinal illness. From a safety perspective, these organisms could be pathogenic to the pupils and steps should be taken in providing and maintaining clean water sources for the pupils.