Bacteriological evaluation of some sachet water on sales in Owerri metropolis, Imo State, Nigeria

Abstract

Aims: Continuous increase in the sale and indiscriminate consumption of packaged drinking waters in Nigeria is of public health significance. In order to safe guard public health, it is essential that the available packaged water is of the highest quality. This study was carried out to evaluate the bacteriological quality of packaged water on sale in Owerri metropolis, Imo State of Nigeria. Methodology and Results: From 30 registered sachet water factories, 8 samples each was purchased randomly fifteen of the brands of sachet water all over Owerri metropolis in Imo State, Southeastern Nigeria. These were analyzed for presence of bacterial indicators of water quality. Four weeks later, a second batch of the samples was collected from other brands. A mean plate counts was taken and the organisms from each water sample identified using standard procedures. The results showed that 11 (73.3%) sachet water brands had growths of pathogenic organisms in the first batch while 10 (66.6%) had growth in the second batch. The isolates were identified to be Klebsilla spp., Serratia spp., Proteus spp., Pseudomonas aeruginosa and Chromobacterium spp. The study showed that Klebsiella pneumoniae [7(29.2%)] was the most predominant. This was closely followed by Serratia spp. [6(25.0%)] and Proteus mirabilis [6(25.0%)]. Pseudomonas aeruginosa [3(12.5%)] and Chromobacterium spp. [2(8.3%)] was least predominant. Mean total heterotrophic bacteria plate counts (HPC) per millilitre ranged from 0.0 to 6.0 x 10 2 CFU/mL at 22 ° C and 0.0 to 7.0 x 10 2 CFU/mL at 37 ° C (first batch) and 0.0 to 5.0 x 10 2 CFU/mL at 22 ° C and 0.0 to 10.0 x 10 2 CFU/mL at 37 ° C for the second batch. Thus they fell below the United States Environmental Protection Agency (USEPA) and World Health Organization (WHO) drinking water standard of 100 HPC per millilitre of water. Bacteriological examination of different brands of sachet water samples collected from different locations showed that only Vince water and Akudo table water was found to be safe for drinking while the other brands of sachet water from mobile vendors in Owerri metropolis was not potable. Conclusion, Significance and Impact of study: Hence, the bacteriological quality of some of the brands of sachet water on sale in Owerri was of poor quality index. The study suggests that sachet water could be a route of transmission of enteric pathogens among the populace. In order to safe guard public health, highest quality brands of sachet water is therefore advocated.