Microbiological Assessment of Selected Samples of Bottled Water Sold in Kwale Delta State Nigeria.

Abstract

This research work is aimed at investigating the presence of microbes in selected samples of bottled water in Kwale, Delta State. A total of twenty-six (26) bottles of mineral water (thirteen brands) were obtained from retailers in Kwale of Delta State and all were produced domestically. The bottled water samples were microbiologically examined using the presumptive test and spread plate technique, gram staining technique and various biochemical tests were used for the identification, while for the fungus isolated the cultural and morphological characteristics were noted. The bottled water samples were physically and microbiologically examined, which entailed taking note of the date of manufacture, date of expiration, net volume and method of sterilization. Four brands (samples BW2, BW3, BW8 and BW12) had manufacturing and expiration date and no sterilization methods were written on all the brands. Eleven out of the thirteen brands had pH within the specified range. The total microbial counts of each brand at 24 hours, the bacterial count ranges from 3.5 to 12.5 cfu/ml while the fungal count ranges from 1.4 to 15.2 cfu/ml at 24-72 hours. The bacterium
isolated using the presumptive test method which was Escherichia coli, while bacteria isolated from each bottled water samples include: E. coli and Streptococcus species, and the fungus isolated from the bottled water samples was Aspergillus species. This present result showed that the water samples examined did not meet the required standard.