Assessment of Heavy Metal Concentration in Soils Around Geita the Gold Mine, Tanzania

Authors

Mariam G. MgendiFollow
Mkabwa L. K Manoko, udsmFollow
W.J.S. Mwegoha, The University of Dodoma, TanzaniaFollow
C. Southway C. Southway, University of KwaZulu Natal, South AfricaFollow

Abstract

Health issues related to gold mining cannot be underestimated. Gold mining produce acid mine drainage (AMD), which in turn releases heavy metals into the nearby environment, hence causing environmental pollution. Heavy metals are naturally very toxic, thus pose a great health concern especially when their concentration exceeds the recommended permissible limits. In this study, concentrations of five heavy metals—including Pb, Ni, Cr, Cu and Zn—were assessed in the soil around Geita Gold Mine (GGM). A total of 17 sampling sites were established from which the soil samples were collected at 0-15cm and 15-30cm soil depth. The concentration of both total and available metal concentrations from each soil sample was determined using the Inductive Coupled Plasma-Optic Emission Spectrometry (ICP-OES) Varian 720-ES. Soil characteristics—namely pH, CEC, organic carbon percentage and clay—were also determined to assess their influence on heavy metals availability. The highest total metal concentration observed in the soil was 212.4mg/kg for Cr, followed by 71.0mg/kg, 66.2mg/kg, 61.2mg/kg and 50.2mg/kg for Zn, Cu, Pb and Ni, respectively; while the highest available metal concentration observed was 26.16mg/kg, 20.13mg/kg, 17.99mg/kg, 7.43mg/kg and 2.10mg/kg for Cu, Zn, Pb, Ni, and Cr, respectively. Generally, the concentration of all heavy metals studied—except Zn—were found higher than the safe permissible limits, indicating some degrees of soil pollution. Such trends raise a concern about the quality of local foods grown in the area, and the need to remedy the polluted soil. However, a Monte Carlo Permutation test showed that none of the soil characteristics assessed had significant influence on heavy metals availability in the soil (P> 0.05).

Recommended Citation

G. Mgendi, Mariam; Manoko, Mkabwa L. K; Mwegoha, W.J.S.; and C. Southway, C. Southway (2021) "Assessment of Heavy Metal Concentration in Soils Around Geita the Gold Mine, Tanzania," Journal of Humanities and Social Sciences: Vol. 09 : No. 3 , Article 5.
Available at: https://doi.org/10.56279/jhss.v9.i3.0