Heavy metal concentrations in five fish species from the Gulf of Guinea and their human health implications

A major impact of marine pollution is the contamination of fish, which has become an issue of concern due to the potential adverse human health effects. Therefore, this study assessed heavy metal (Cu, Ni, Fe, Cd, Pb, Zn and Hg) concentrations in different parts of five fish species namely S. aurita, E. encrasicolus, S. colias, B. auritus and P. bellottii from the Gulf of Guinea and their implications for human health. The results showed that Cd and Pb concentrations in all the analysed fish species were below their respective detection limits of 0.01 mg kg⁻¹ dw and 0.05 mg kg⁻¹ dw and thus pose low health risks. On a wet weight basis, the mean metal concentrations in fish muscle ranged from 0.04 to 0.31 mg kg⁻¹ for Cu, 1.23 to 3.87 mg kg⁻¹ for Fe, 0.20 to 0.39 mg kg⁻¹ for Ni, 0.17 to 0.42 for Zn, and 0 to 0.05 mg kg⁻¹ for Hg. Although these measured metal concentrations were within permissible limits for human consumption, the calculated hazard quotients indicated that the concentrations of Hg in S. aurita, S. colias and B. auritus pose significant health risks.