Thesis Abstract

Thesis Overview

<p> </p><p>This study was undertaken to assay the elemental concentration in some Irish potatoes and soils from farmlands in an ex-mining area at Dahwol-vwana village, Jos-south L.G.A, Plateau state, Nigeria. The total heavy metal concentrations (for Irish potato and soil samples) were obtained using Atomic Absorption Spectrometer. It was observed from the soil sample concentration values gotten at the end of the AAS analysis (Pb, ranges from 0.0445-3.9343ppm; Cd, from 0.0086- 0.1200ppm and Zn, from 0.0751-39.0302ppm) are higher than the concentration values obtained from control area (Pb- 0.0088ppm, Cd-0.0029ppm and Zn-0.0101ppm), but lesser than the international threshold values (<strong>EU</strong>:- Pb-300ppm, Cd-3.0ppm and Zn-300ppm. <strong>USA</strong>: - Pb- 300ppm, Cd-3.0ppm and Zn-250ppm. <strong>UK</strong>:- Pb-70ppm, Cd-1.4ppm and Zn-200ppm). While that of Irish potatoes: - Pb, ranges from 0.0741-1.5042ppm; Cd, from 0.0081-0.0931ppm and Zn, from 0.1038-88.0503ppm). A modified sequential extraction procedure of Tessier <em>et. al</em>., (1979) was used in separating the total metal concentrations into four operationally defined fractions (exchangeable and carbonate, Fe and Mn oxides, organic matter, and residual fractions). Where it was discovered that the bulk of metals were partitioned to the residual fraction (Zn- 138.85ppm, Pb-55.59ppm and Cd-2.5ppm) which implies that the soils of the farmland are not polluted by any of the metals studied. Pollution indices also as compared with Banat <em>et. al</em>., (2005) standards, indicated minimal contamination of the soils matrix with Cd, which had enrichment factor value of</p><p>15.4 and I-geo factor of 4. The bulk partitioning of the metals onto the residual fraction indicates a lithogenic origin of the heavy metals, i.e. the heavy metals were directly inherited from the parent material, and also a low risk of contaminant transfer under normal cultural practices. However, heavy perturbation of the soil, such as mining, would lead to significant pollution of soil, and water bodies as well enhanced Irish potatoes and other plants uptake of the metals, thereby resulting in a threat of biomagnifications.</p><br> <br><p></p>