ASSESSMENT OF HEAVY METAL POLLUTION POTENTIALS AND DISTRIBUTIONS IN THE TAILINGS FROM ITAGUNMODI GOLDMINE OSUN STATE, NIGERIA

Abstract

The speciation of some heavy metals (Cu, Ni, Cd, Cr, Zn and Fe) in Itagunmodi goldmine tailing was determined using multi- step sequential extraction. Physico-chemical properties such as pH, conductivity, Cation Exchange Capacity, organic matter, residual humidity and particle size were also analyzed. The percentage recovery of Ni ranged from 95.25-99.24%. The high Mobility factor and Bioavailability factor values of tailing Ni may be interpreted as symptoms of relatively high liability and biological availability of the metals in tailings. Similar characteristics distribution patterns were observed for Cd, Cr, Fe and Zn except Cu. The pollution characteristics of Cu, Ni, Cd, Cr, Zn and Fe in goldmine tailing were studied. The results indicate that the contamination degree followed the sequence of 5>1>3>2>4. The concentrations of Cu, Zn Ni and Cr in the soil were low, so their potential ecological risks were far lower than other heavy metals and exerted no potential harm to environment. The bioaccumulation and translocation factors of Ni, Cd, Cr, Zn and Cu in Platycerium coronarium, Vernonia amigdalina, Chromolena odorata and Talinum fruticosum were investigated. Bioaccumulation factor of all element are lower than one which indicated accumulator. Translocation factor of Cd, Ni and Cr more than one and hence, Platycerium coronarium and Chromolena odorata could be considered as potentially useful for remedying Cd, Ni and Cr contaminated soil.