Spatial distribution, bioaccessibility, and human health implications of potentially toxic elements in mining-impacted topsoils in Obuasi Municipality of Ghana

Environ Geochem Health. 2024 Jul 8;46(8):291. doi: 10.1007/s10653-024-02028-w.

Abstract

Potential toxic elements emanating from extracted ores during gold processing present occupational and unintentional health hazards in communities, the general populace, and the environment. This study investigated the concentrations and potential health effects of metal content in the topsoils of Obuasi municipality, which has been mined for gold over the past century. Surface topsoil samples, sieved to 250 µm, were initially scanned for metals using x-ray fluorescence techniques, followed by confirmation via ICP-MS. In vitro bioaccessibility assays were conducted using standard methods. The geoaccumulation indices (Igeo) indicate high enrichment of As (Igeo = 6.28) and Cd (Igeo = 3.80) in the soils, especially in the eastern part of the municipality where illegal artisanal mining is prevalent. Additionally, the southern corridor, situated near a gold mine, exhibited significant levels of As and Mn. Results obtained for the total metal concentrations and contamination indices confirmed the elevation of the studied potential toxic elements in the Obuasi community. A hazard index value of 4.42 and 3.30 among children and adults, respectively, indicates that indigens, especially children, are susceptible to non-cancer health effects.

Keywords: Ecological risks; Environmental pollution; In-vitro bioaccessibility assay; Mining activities; Soil contamination.

MeSH terms

  • Adult
  • Arsenic / analysis
  • Biological Availability
  • Child
  • Environmental Exposure
  • Environmental Monitoring / methods
  • Ghana
  • Gold*
  • Humans
  • Metals, Heavy / analysis
  • Mining*
  • Risk Assessment
  • Soil Pollutants* / analysis

Substances

  • Soil Pollutants
  • Gold
  • Metals, Heavy
  • Arsenic