ABSTRACT
Heavy metals are naturally occurring elements, which have a high atomic weight and a density at least 5 times greater than that of water. This research evaluates the physiochemical analysis and some heavy metals content in fish from the Okerenkoko River, Nigeria. The physicochemical parameters of the water samples were measured in situ and the laboratory. The parameters include pH, electrical conductivity, total dissolved solids, suspended soil, turbidity, alkalinity, hardness, sulphate, nitrate, ammonium-nitrogen, phosphate, chloride, calcium and magnesium. This research also examines the accumulations of nine heavy metals in Fish, including Potassium (K), Iron (Fe), Copper (Cu), Zinc (Zn), Manganese (Mn), Nickel (Ni), Cobalt (Co), Lead (Pb), Cadmium (Cd). Thus, determined by atomic absorption spectrophotometry (sampled from the Okerenkoko River). Physicochemical parameters of the water samples and heavy metal concentrations in the fish species obtained also from Okerenkoko River were examined using standard methods. And its values were below WHO and FEPA limits. However, with exception of Turbidity, alkalinity, and chloride which go beyond permissible limits. The order of mean concentrations of heavy metals in fish samples from high to low is shown as follows: Potassium (372.49 mg/l) > Iron (25.782 mg/l) > Zinc (6.4186 mg/l) > Copper (3.1842 mg/l)> Manganese (2.6085 mg/l)> Nickel (0.4216mg/l)> Cobalt (0.178mg/l)>Lead (0.071mg/l).>Cadmium (0mg/l). Heavy metals concentration in fish exceeded WHO and FEPA standards. In exemption of, Cadmium and Lead, these values exceeded WHO, and FEPA limits thus suggesting that the fish and water of Okerenkoko River, are unfit for consumption, therefore, frequent monitoring of physicochemical parameters and scrutiny of fishes of Okerenkoko River is imperative.
