Human Health Risks Assessment of Some Heavy Metals in Oreochromis niloticus from a Tropical Reservoir

Abstract

This study evaluated the human health risks of Mn, Fe, Zn, Cu, Cd, Pb, Cr, Co and Ni in Oreochromis niloticus inhabiting Agodi reservoir in Ibadan, Nigeria. The metals’ concentrations were determined with atomic absorption spectrophotometer. Carcinogenic and non-carcinogenic risk of consumers from the intake of metals in the fish was evaluated by Health Risk Index (HRI), Health quotient (HQ) Target Hazard Quotient (THQ) and Target cancer risk (TR). The metal concentrations in the fish were below the recommended limit by Environmental Protection Agencies. HRI and HQ of each examined metal was greater than one, indicating that there was potential non- carcinogenic health risk associated with the consumption of the fish. However, the THQ and TR were less than one. This indicated that Oreochromis niloticus will not pose any immediate carcinogenic threat to its consumers. It is therefore recommended that only eco-friendly activities should be permitted in/around aquatic ecosystems especially Agodi reservoir in order to keep contaminants below safety limit.