Microbiological Dynamics of Potable Water under Storage Durations

Abstract

The microbiological dynamics of potable water under different storage durations was carried out. tap and sachet water samples obtained from Elele were analyzed weekly for changes in total aerobic plate bacterial count, coliform count, Escherichia coli count, Salmonella-Shigella­ count, Vibrio cholerae count and fungal count during storage. Nutrient agar, MacConkey broth, eosin methylene blue agar, Salmonella-Shigella­ agar, thiosulphate citrate bile salt sucrose agar and Sabouraud dextrose agar were respectively used for the enumeration. The pour plate technique was employed and the statistical analyses used were analysis of variance and standard deviation. The total aerobic plate bacterial count for the borehole and satchet water samples ranged from 4.26 ± 0.4Log₁₀cfu/mL   to 4.78 ± 0.1Log10cfu/mL and 0 ± 0.00Log₁₀cfu/mL to 4.53 ± 0.2Log₁₀cfu/mL respectively. The coliform count ranged from 9MPN/100mL to 240MPN/100mLand 0 ± 0.00MPN/100mL to 28MPN/100mL respectively. The Escherichia coli count ranged from 1.78 ± 0.5Log10cfu/mL to 3.59 ± 0.2Log₁₀cfu/mL and 0 ± 0.00Log₁₀cfu/mL respectively. The Salmonella-Shigella­ and Vibrio cholerae counts were 0 ± 0.00Log₁₀cfu/mL. The fungal count ranged from 0 ± 0.00Log₁₀cfu/mL to 2.90 ± 1.0Log₁₀cfu/mL and 0 ± 0.00Log₁₀cfu/mL. The bacteria isolated from the water samples were   Escherichia coli, Enterobacter species, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella species and Bacillus species.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            Drinking of potable tap water stored for over a period of time may pose threat to the consumers if sanitary measures are not put in place during treatment of water.

Key words: Dynamics, durations, microbiological, potable, storage