Microbiology and Physicochemical Characteristics of Surface Water from a Local Refinery Site in Port Harcourt, Nigeria

Abstract

Water plays a vital role in maintaining human health but due to an increase in industrialization, urbanization and other anthropogenic activities, surface water pollution is on an increase. This research was carried out to investigate the microbiological and physicochemical status of a crude oil polluted surface water in Iwofe River, Rumuolemini, Port Harcourt. Samples were collected from two points (Upstream and Downstream) bi-monthly for a period of three months. The THB counts for the upstream and downstream samples were 1.7 × 108cfu/ml and 1.4 × 108 cfu/ml, respectively while the THF counts for the samples were 3.0 × 106cfu/ml and 1.4 × 106 cfu/ml, respectively. Hydrocarbon utilizing bacterial (HUB) counts were higher in the upstream (1.5 × 106cfu/ml) than downstream (4.3 ×105cfu/ml) location of the Iwofe River. The Hydrocarbon utilizing fungal (HUF) count ranged from 1.0 × 105cfu/ml to 1.4 × 105 cfu/ml in the upstream and downstream water samples, respectively. The results of all the microbiological parameters analyzed indicated that the total heterotrophic bacterial (THB) and Total heterotrophic fungal (THF) counts were higher in the upstream than in the downstream location. The Most Probable Number (MPN) method used for the determination of coliform counts revealed the presence of coliforms both upstream and downstream, with an MPN index of 1,600/100ml of each sample. Some of the bacterial species isolated were Staphylococcus aureus, Escherichia coli and Vibrio cholerae while the fungal isolates included Aspergillus fumigatus, Penicillium species and Alternaria species. The high level of oil contamination poses a great health threat and there is a need for remediation of the aquatic ecosystem.