OCCURRENCE OF FAECAL COLIFORMS FROM SELECTED BOREHOLE WATER IN LAPAI METROPOLIS, NIGER STATE, NIGERIA

Abstract

This study was carried out to assess the coliform bacteria contamination of selected borehole water in Lapai metropolis. Thirty-six (36) borehole water samples were collected from four (4) different cardinal points (North, South, West and East). The water samples were analyzed for selected physico-chemical parameters. Total bacteria count and the Most Probable Number (MPN) of coliforms were also carried out on the water samples, based on standard experimental procedures. Isolates from positive MPN bottles were sub- cultured on Eosin Ethylene Blue (EMB) Agar. They were subjected to Gram staining and other biochemical tests. Results revealed that bacteria count was from 1.43 x 10⁸ to 1.45 x 10⁹. Coliform counts ranges from 1 – 20 MPN/100 mL. There was no significant difference in MPN values at 5% significant level (P> 0.05). Escherichia coli, 35 (48.61%) predominates among the bacteria identified, while the least bacteria isolated wasPseudomonas sp, 2 (2.77%). Physico-chemical properties of borehole water such as temperature range from 23.0^oC - 29.0^oC, pH from 6.68 - 8.80, and turbidity values ranges from 2 – 6 FTU. Significant difference was observed in the pH level and Turbidity of the sampled water at 5% significant level (P < 0.05), while significant difference was not observed in the Temperature of the sampled water at 5% significant level (P> 0.05). The results showed that the water samples failed to meet the World Health Organization (WHO) standard for portable water, because the water samples harbor bacteria contaminants. It is therefore recommended that a proper treatment be carried out before use.