Assessment of Heavy Metal Pollution in a Gold Mining Site in Southwestern Nigeria

Abstract

The unwanted release of environmental contaminants predisposed by mining activities had reached an alarming proportion that deserves attention. Hence, the purpose of this study was to determine the degree of heavy metal contamination which soil and plants were exposed to in Ijana gold mining site, southwestern Nigeria. To this, Zinc, Arsenic, Cadmium, Lead, Nickel, Chromium and Copper concentrations were measured using Atomic Absorption Spectrometry. Obtained values were used to evaluate the degree of soil pollution and plant contamination using physicochemical analysis, bioaccumulation factor and translocation factor of metals into plant in surrounding mine site. Zinc and Lead show a slightly higher presence than other metals tested. Mean concentrations of Zn (0.70 mg/kg), As (0.09 mg/kg), Cd (0.13 mg/kg), Pb (0.216 kg/mg), Ni (0.08 mg/kg), Cr (0.148 mg/kg), Cu (0.629 mg/kg) in soils around the mining area were considerably the same with the concentration of metal accumulated in plant, respectively. All metal tested showed minimal accumulation in plants. Translocation factor also implicated Zn to be the highest among all the heavy metals analyzed.