Assessment of heavy metal concentrations in fish, water and sediment of Koramar Wanke Dam Gusau, Zamfara State, Nigeria

Abstract

Pollution of heavy metals in water bodies is a threat to public water supply as well as to consumers of fishery resources. This study was aimed at investigating the distribution of heavy metals in some fish species, water column and sediment of Koramar Wanke Dam. Water and sediment samples were collected from 4 different sampling stations across the dam, while fish species (Bagrus bayad, Clarias gariepinus, and Oreochromis niloticus,) were bought at Dabar Masunta fish landing site of the dam on monthly basis for a period of three months from August 2023 to October 2023. Heavy metals Cadmium (Cd), Copper (Cu), and Lead (Pb) were analyzed in water samples, fish samples and sediment samples the dam using Atomic Absorption Spectrophotometry (AAS). The heavy metal level ranges in fish samples examined were Cd, 0.02 mg/kg-0.04mg/kg; Cu, 0.02 mg/kg-0.08 mg/kg; and Pb, 0.02 mg/kg-0.06 mg/kg. The result also showed the mean concentration range of 0.01-0.02 mg/l for Cd; 0.06-0.12mg/l for Cu; and 0.03-0.11 mg/l for Pb in water samples examined. The mean concentration of detected in the sediment samples ranged from 0.08-0.29 mg/kg; 0.14-0.21 mg/kg; and 0.08-0.17 mg/kg for Cd, Cu, and Pb respectively. The results obtained show minimal concentrations of the examined heavy metals in the water body below the recommended permissible levels. However, it is advisable to continue to take adequate measures to prevent entry of sewage, toxic substances and contaminants from industrial sources and agricultural residues from pesticides and insecticides into the water body, and to conduct further study at another period.