IMPACTS OF INDUSTRIAL EFFLUENTS ON THE WATER QUALITY OF THE RECIPIENT WATER

ABSTRACT

Untreated industrial effluents are sources of pollution particularly in aquatic ecosystems where they alter the quality of water and threaten aquatic life. This study was carried out to determine the alterations to the physicochemical, microbiological and heavy metal concentrations of Ikpoba River upon the input of industrial effluents from a beverage industry in Benin City, Nigeria. The water samples were collected from upstream, discharge point and downstream portion of the river. The samples were analysed using standard methods. The results obtained showed that the physicochemical properties of the water samples were within regulatory limits of the USEPA and WHO with the exception of pH in the discharge point and downstream samples. The concentrations of selected heavy metals (Cr, Cd and Fe) exceeded the limits recommended by the USEPA for heavy metals in water. Heterotrophic and coliform counts of the bacteria present in the samples ranged from 1.75±0.75 x 10 4 cfu/ml to 3.20±0.99 x 10 4 cfu/ml, and 37.25±4.27 to 91.25±13.94 cfu/ml. These bacterial counts pose a potential health risk to people using water from the river. The values obtained for the physicochemical, heavy metals and microbiological properties of the water samples in the three sampling points were in the following order: discharge point > downstream > upstream. This showed that the discharge of effluents into the river affected the quality of the water. Proper treatment for removal of heavy metals and microbial contaminants is recommended.