Human and Ecological Risk Assessment of Potentially Toxic Elements in Soils from Artisanal and Small-Scale Gold Mining Areas.

Abstract

Artisanal and small-scale gold mining (ASGM) plays a significant role in the economies of many developing countries, including Ghana, but it is also associated with serious environmental and health risks due to the release of potentially toxic elements (PTEs) into the ecosystem. This study assessed the concentrations, sources, ecological risks, and human health implications of PTEs in soils from Gbani, a prominent ASGM area in Ghana. Using a Niton XL3t GOLDD+ field portable X-ray fluorescence spectrometer, the levels of key metals such as As, Pb, Cd, Cu, Zn, Cr, Ni, Co, Ti, V, and Mn were quantified. Multivariate statistical methods, including Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF), were employed to identify pollution sources. Pollution indices such as the Geo-accumulation Index (Igeo), Enrichment Factor (EF), and Potential Ecological Risk Index (PERI) indicated moderate to high contamination levels, primarily of anthropogenic origin. Non-carcinogenic and carcinogenic risk assessments were conducted for both children and adults via ingestion, inhalation, and dermal pathways. While most metals remained below regulatory thresholds, elevated concentrations of Cd, Cu, Zn, and V exceeded Dutch intervention values, suggesting a potential ecological threat. However, the Hazard Index (HI) and Hazard Quotient (HQ) values for all exposure pathways were below 1, indicating no immediate health risk. The study highlights the need for regular environmental monitoring and the implementation of mitigation strategies to safeguard human health and ecological integrity in mining communities.