Effect of Convergent Rays on Coliform and Total Culturable Heterotrophic Bacteria in Water

Abstract

Aims: Verification of the effect of convergent rays on coliform and total culturable heterotrophic bacteria counts (TCHBC) in River (surface water), well and borehole (underground) water bodies around Choba and Aluu communities. Place and Duration of Study: The efficiency of convergent ray’s disinfection of surface (Rivers) and underground (well and Borehole) water bodies was conducted on Choba and Aluu communities water samples in River State, Nigeria in the Department of Microbiology laboratory, University of Port Harcourt between November, 2012 to December, 2013. Methodology: Different volumes of water samples were exposed to converged rays for 0, 2, 4, 6 and 8 hours intervals using a circular-dish ray concentrator covered with Aluminum foil paper as the reflecting material. The TCHBC was determined using bacterial plate counts while the coliform population was determined using the most probable number multiple tube technique. Results: The study showed that coliform and TCHBC population had the same logarithmic values at 0 hour and after 2 hours of exposure (1.2 logMPN/100 ml and 2.2 log cfu/ml). The coliform population of the 2 and 4 Litre aliquots decreased from 1.2 and 2.2 to 0.0 log MPN/100 ml after 8 hours while the total culturable heterotrophic bacterial population decreased from 2.1 and 2.2 for 0 hour to 0.9 and 1.2 log cfu/ml after eight (8) hours of exposure. The pH of water samples were as follows; River water 5.0, Well 6.4 and borehole 7.0 respectively. Conclusion: The research was able to provide satisfactory and dependable results compared to World Health Organization and Environmental Protection Agency WHO and EPA drinking water standard with MPN/100 ml to be 0.0 log MPN/100 ml and 0.9 and 1.2 cfu/ml total culturable heterotrophic bacteria count after 8 hours of exposure compared to 1.2 log MPN/ml and 2.2 logcfu/ml before the convergent rays exercised; thus, the study justifies the use of convergent rays for water disinfection.