Bacteriological and Physicochemical Assessment of Selected Brands of BottledWater in Ilorin, Nigeria

Abstract

 Twenty different brands of bottled water sold in Ilorin metropolis, Kwara State, Nigeria were examined for their
bacteriological and physicochemical qualities. Bacteriological analyses were carried out to determine the counts of
heterotrophic bacteria, total coliform and faecal coliform. Physicochemical qualities such as pH, chloride content, total
hardness and total suspended solids were also examined. The heterotrophic bacterial count ranged from 0 to 121cfu/ml while
the total coliform count ranged from 0 to 1100 coliform/100ml of the sample. There was absence of faecal coliform in the
bottled water samples. The pH, chloride content, total hardness and total suspended solids ranged from 6.50 to 8.40, 3.55 to
4.79mg/l, 1 to 90mg/l, and 0.001 to 0.003 g/100ml respectively. The bacterial species isolated belong to the genera
Staphylococcus, Micrococcus and Aeromonas. In terms of quality, 19 (95%), 18 (90%) and 0 (100%) of the 20 brands of
bottled water samples met the standard for heterotrophic bacteria, total coliform, and faecal coliform respectively. All the
bottled water samples conformed to the standard for pH, chloride content, total hardness and total suspended solids. It can be
concluded from this study that 85% of the bottled waters were suitable for drinking with regard to bacteriological and
physicochemical parameters tested. It is recommended that stringent measures should be adhered to in the manufacture of
bottled water, the bottles should be properly capped, and information on the manufacturing date, expiry date and batch
number should be written on the bottles for easy recall.