Health Risks of Heavy Metals in selected Food Crops cultivated in Small-scale Gold-mining Areas in Wassa-Amenfi-West District of Ghana

Abstract

An assessment of heavy metals (Pb, Cu, Zn, Ni, and Cd) in soils, Cassava (Manihot esculenta crantz) and plantain (Musa paradisiacal) was conducted in Wassa-Amenfi-West District, a small-scale gold-mining area in Ghana. Metal levels in soil samples were within the permissible limits of Indian and EU standards even though, the Pollution Load Index (PLI) revealed significant metal loading. PLI values were 26.35, 4.81, 54.18, 2.01 and 1.55 for Cd, Ni, Pb, Zn and Cu, respectively.  Metals in food crops were higher than in soils, with ranges of 19.63-53.93, 19.45-142.39, 99.42-357.15, 27.01-76.21, and 1.42-5.84mg/kg for Ni, Cu, Zn, Pb and Cd, respectively. Pb, Cd, Zn and Cu in plantain exceeded FAO/WHO recommended values while in cassava, Pb, Cd and Zn exceeded recommended levels. Analysis of daily intake of metals (DIM) and health index (HRI) for cassava and plantain showed that local inhabitants were not safe and were at risk of potentially long term health effects from dietary Pb, Cd, Ni, Cu and Zn.

Keywords: Cassava, Ghana, Heavy metals, health risk, Plantain, Wassa-Amenfi-West