QUALITY ASSESSMENT OF SOME BOTTLED WATER SOLD IN SAGAMU METROPOLIS, OGUN STATE, NIGERIA
Keywords:
Bottled water, physicochemical analysis, Microbial quality, Sagamu, Coliform bacteriaAbstract
Water is an indispensable resource needed for the existence of all living things, water plays important role in body metabolism and proper functioning of the cells, ingestion of contaminated bottled water brands poses serious health risks, the aim of this study is to evaluate the physiochemical and microbial quality of bottled water samples in Sagamu, Ogun State. The physicochemical analysis of the samples was carried by evaluating the pH, Turbidity, total dissolved solids, hardness, chloride concentration, nitrate concentration and concentration of heavy metals (Lead, zinc, and cobalt). A pocket digital pH meter was used to determine the pH, hardness of water samples were carried out by using titration method with EDTA solution, determination of chlorides was carried out by titrating water samples with silver nitrate solution, determination of turbidity was carried using a portable turbidity meter, Total dissolved solid was determined with a TDS meter. The microbial analysis of the water samples was carried out by determining the bacterial load using a colony counter, presumptive coliform test was used to confirm the presence of lactose fermenters, and differential coliform test was used to confirm the presence of coliform bacteria. Isolated organisms were identified using selective and differential media, gram stain test, catalase test. The pH of the samples ranged from 6.5-7.4, the total hardness 85.43-112.54 also within the acceptable range of 60mg/l to 120mg/l, turbidity of the samples ranged from 1.2-2.9 NTU, total dissolved solids present ranged from 30.6-39.7, chloride concentration ranged from 21.5 to 42.6, Nitrate concentration ranged from 0-1.4. From the study, it is evident that the physicochemical parameters of the water samples were all within the WHO and NAFDAC accepted ranges, thepH of all samples also fell within the acceptable ranges of 6.5-7.5, however the microbial analysis points out that most of the samples tested positive to coliforms with varying MPN values, sample D and F being the lowest (9), thus the other samples are unsafe for drinking