Evaluation of the Bacteriological and Physicochemical Qualities of Some Brands of Bottled Water Sold in Owerri, Imo State

Abstract

This work was carried out in order to detect the presence of bacterial agent in the bottled water samples, and to evaluate the physicochemical qualities of these bottled water. Twenty samples selected from four different brands of bottled water sold in Owerri, were examined to determine their bacteriological and physicochemical qualities. Bacteriological analyses using Membrane filtration technique was carried out to determine the heterotrophic bacteria, total coliform and fecal coliform counts. Physicochemical qualities were also determined using standard methods. The heterotrophic bacterial count ranged from 0.00 to 12.00 CFU/ml, total coliform count ranged from 0.00 to 7.50 coliform/100ml. There was absence of fecal coliform in the samples. The pH, Color, Turbidity and Conductivity of the samples ranged from 5.18 to 7.28, 0.00 to 18.00 PCU, 0.55 to 1.62 NTU and 16.00 to 262.00 µs/cm respectively.  The Chloride, Iron and Nitrite content of the samples ranged from 16.99 to 27.98 mg/L, 0.01 to 0.07 mg/L Fe, and 0.00 to 0.34 mg/L respectively. The bacterial species isolated belong to the genera Staphylococcus, Proteus, Klebsiella, Bacillus and Escherichia. Quality wise, most of the water samples met the XYZ standard for bacteriological and physicochemical quality for drinking water with the exception of few. It can be deduced from this study, that none of the bottled water is suitable for drinking with regards to the bacteriological and physicochemical parameters tested. Though some samples passed the bacteriological examination, most of them were acidic and therefore not safe for consumption.