Adhesion of Heterotrophic Bacteria on the Surface of Containers Used for Well Water Storage in Garoua (North Cameroon)

Aims: The abundance of heterotrophic bacteria adsorbed on the walls of four types (polypropylene, glass, aluminium, clay) of containers used for well water storage in Garoua was compared.

Methodology: Water samples were obtained from two wells. In each well water sample, 3 sterilized slides of each type of container were introduced, at mid-depth from the surface. Their immersion times were respectively 24, 48 and 72 h. After an immersion time, slides were aseptically removed from the water samples and transferred into sterile test tubes containing 10 ml of saline. The resulting bacterial suspension was used to determine abundance of heterotrophic bacteria adsorbed on the slides.

Results: The maximum abundance of adsorbed bacteria (8.06x104 CFU/cm2 to 2.47x106 CFU/cm2) was obtained on the clay slide while the minimum (45 CFU/cm2 to 5.90x103 CFU/cm2) was recorded on the aluminium slide from first to third day of water storage. The bacterial abundance differs significantly depending on the slide type and the duration of water storage (P <0.001).

Conclusion: Rather than using massively clay pots for drinking water storage, people in North Cameroon are recommended to use metallic or glass containers to reduce bacterial adhesion.