Heavy metal bioaccumulation in food crops grown around Babban Tsauni gold mines and assessment of farmland soil contamination

K. A. Odelami; Y. Musa

doi:10.61298/pnspsc.2026.3.313

Authors

K. A. Odelami
[email protected]

Department of Physics, Kaduna State University, Kaduna, Nigeria
Y. Musa
Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria

Keywords:

Heavy metals, Bioaccumulation factor, Farm soil, Soil contamination, Gold mining

Abstract

Heavy metal bioaccumulation in food crops is a serious environmental and public health concern, especially in regions affected by artisanal mining. This study assessed the bioaccumulation potential, expressed as bioaccumulation factor (BF), of selected heavy metals---lead (Pb), arsenic (As), nickel (Ni), chromium (Cr), manganese (Mn), zinc (Zn), cobalt (Co), and iron (Fe)---in twelve food crops, comprising four tubers and eight grains cultivated around the Babban Tsauni gold mines. The contamination status of nearby farmlands was also evaluated. Heavy metal concentrations were determined using instrumental neutron activation analysis (INAA) and X-ray fluorescence (XRF). The mean BF values for tubers were 19.176 (Pb), 0.015 (As), 0.101 (Ni), 0.796 (Cr), 0.079 (Mn), 2.839 (Zn), 1.334 (Co), and 0.879 (Fe), while those for grains were 43.290 (Pb), 0.258 (As), 0.419 (Ni), 2.162 (Cr), 0.152 (Mn), 3.827 (Zn), 0.529 (Co), and 0.653 (Fe). Pb showed the highest bioaccumulation in both crop groups, followed by Zn, indicating strong plant uptake in contaminated soils. The pollution load index (PLI = 2.25) indicated soil pollution, whereas the overall potential ecological risk index (RI = 87.61) indicated low ecological risk. The occurrence of Zn and Mn may be attributed mainly to natural geogenic sources rather than human activity. The elevated accumulation of Pb and Zn calls for appropriate remediation strategies, including land-use restriction, crop selection, and supervised mining in mining-impacted agricultural areas.

Dimensions

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