Comparative Assessment of Bacteriological Quality of Drinking Water using Membrane Filtration and Multiple Tube Fermentation Methods

Abstract

Comparative assessment of 13 different drinking water sources (sachet, bottled, pipe borne and borehole) was carried using the conventional direct coliform plate count (CPC), multiple tube fermentation (MTF) and membrane filtration (MF) techniques. Physicochemical analyses indicated that the water samples meet WHO guidelines for pH, temperature and turbidity. However, the bacteriological analyses showed that none of the drinking
water source is potable according to WHO guidelines. The confirmatory and completed tests revealed the presence of faecal coliforms in some of the samples. Findings of this study demonstrate that CPC is a poor method to assess water potability while MTF and MF techniques compared relatively well. There is need to intensify effort at the monitoring of activities in the rapidly expanding packaged water industry with a view to improving the standards.

Keywords: drinking water, membrane filtration, multiple tube fermentation, coliform