Physicochemical and Microbiological Assessment of Utaewa Estuary Water

Abstract

Most communities in the oil rich Niger Delta find it difficult to access to potable water due to constant pollution of their natural water sources. The sole aim of this study was to examine the microbiological and physicochemical qualities of the Estuary water at Utaewa to ascertain its suitability for potable use. Standard culture dependent techniques as well as metagenomics approach using Next Generation Sequencing (NGS) on Illumina Miseq platform was used to determine the microbiological characteristics while standard analytical procedures were employed to ascertain the physicochemical properties of Utaewa in Imo River. The average microbial counts ranged as follows: Total Heterotrophic Bacteria; 2.17±0.08x106 to 2.23±0.08x106 cfu/ml, Hydrocarbon Utilizing Bacteria; 1.03±0.06x105 to 1.39±0.08x105 cfu/ml, Total Heterotrophic Fungi; 1.23±0.13x105 to 1.64±0.09x105 cfu/ml, Hydrocarbon Utilizing Fungi; 7.9±0.21x103 to 8.6±1.00x103 cfu/ml. Bacterial isolates belonging to the genera Escherichia, Citrobacter, Bacillus, Salmonella, Shigella, Proteus, Flavobacterium, Vibrio, Micrococcus and Pseudomonas. were isolated and identified. The fungal isolates belonged to the genera Aspergillus, Rhizopus, Fusarium, Penicillium, Saccharomyces and Candida. On the other hand, Unknown (50.16%), Acinetobacter (8.34%), Ignatzschineria (4.73%), Planctomyces (3.28%), Anaerospora (3.27%), RS62 (2.73%), Methylophaga (1.64%), Wohlfahrtiimonas (1.31%), Myroides (1.23%) and Candidatus (0.95%) were captured by metagenomics analysis at the generic level. All the physicochemical parameters conformed to WHO and NIS standards for potable water except for Turbidity and Magnesium. Cultural methods used in this study were able to identify many potential water borne pathogens, metagenomics captured more microbial groups and give a better insight to bacterial composition and diversity. The presence of theses pathogenic bacteria underlies poor water quality and can pose public health threat to man and aquatic fauna. There is need to adhere to good hygienic practices and minimize the direct discharge of waste without proper treatment.