Human health risk assessment from heavy metals in three dominant fish species of the Ankobra river, Ghana

This study assessed heavy metal contamination of fish and its associated health risk to communities around the Ankobra River in the Western Region of Ghana. Species of fish randomly collected from different sections of the river were analyzed for Cd, Ni, Zn, Pb, Mn, Hg, As, Co and Cr using Atomic Absorption Spectrophotometry. Three commonly consumed fish species, Clarias gariepinus, Sarotherodon melanotheron and Pseudotolithus senegalensis, were analyzed. The health risks were assessed based on the potential non-carcinogenic effect associated with the daily consumption of fish by communities around the river. Concentrations of all the metals were higher in gills than the muscles of all three species. On average, levels of Mn (6.65 +/- 7.30 mg.kg(-1)), Zn (2.24 +/- 1.99 mg.kg(-1)) and Hg (3.06 +/- 1.53 mg.kg(-1)) in all three species were above the permissible limits recommended by the World Health Organization. The health risk estimated for all the heavy metals was < 1, significantly below the >= 1 index associated with the incidence of cancer. This suggests that fish species examined in this study pose no significant non-carcinogenic risk and are safe for human consumption.