Bacteriological assessment of the recreational water of Bacuit Bay, El Nido, Palawan, Philippines

Abstract

In early 2018, the recreational water of Bacuit Bay in El Nido, Palawan, Philippines was declared by the Department of Environment and Natural Resources (DENR) to be contaminated with a coliform count of 1,139 MPN 100 ml-1 sample water. Although water quality assessment was done in the area, no study was conducted on the associated clinically important bacterial pathogens. This study was conducted to assess the microbial contamination and presence of some pathogens, and to compare microbial contamination between 2018 and 2019 in Bacuit Bay. Surface water samples were collected from 11 stations in Bacuit Bay in June 2018 and June 2019. The multiple tube fermentation technique was done to assess the coliform contamination. Selective and differential microbial culture media were used to isolate some clinically important pathogens. Results showed that in 2018, all stations were positive with coliform where nine out of 11 stations exceeded the acceptable level of coliform count for recreational waters. Also, there were eight clinically important putative bacterial pathogens isolated, the Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Shigella sp., Salmonella sp., Vibrio parahaemolyticus and Vibrio cholerae. In 2019, the coliform count and the associated bacterial pathogens decreased in number with only two out of 11 stations exceeded the acceptable level and two of eight bacterial pathogens were detected. These could be attributed to the activities that were conducted by the local government unit of El Nido to mitigate the pollution in the coastal environment.