Assessment of Hydro-geochemical and Radiological Contamination Associated with Artisanal and Small-Scale Gold Mining and Its Implications for Human Health and the Environmental Quality

<title>Abstract</title> <p> <bold>Background</bold> Artisanal and small-scale gold mining (ASGM) is widely practiced across low- and middle-income countries and constitutes a major source of environmental contamination and public health risk. The use of mercury amalgamation, poor waste management practices, and the disturbance of mineralized host rocks contribute to the release of toxic heavy metals and naturally occurring radioactive materials (NORMs) into soils, surface water, and groundwater systems. <bold>Objective</bold> This systematic review aimed to evaluate the extent, pathways, and human health implications of geochemical, radiological, and hydrogeological hazards associated with ASGM activities, with particular emphasis on exposure risks to miners and surrounding rural communities. <bold>Methods</bold> A systematic literature review was conducted using peer-reviewed journal articles, reports, and technical documents published over the last two decades. Studies addressing heavy metal contamination, radionuclide exposure, groundwater degradation, and associated health risks in ASGM environments were critically analyzed. Data were synthesized thematically under geochemical, radiological, and hydrogeological impact domains. <bold>Results</bold> The review reveals consistently elevated concentrations of mercury, arsenic, lead, cadmium, and cyanide in soils and water bodies near ASGM sites, frequently exceeding international guideline limits. Radiological assessments indicate enhanced exposure to NORMs, particularly ^226Ra and ^232Th, among miners and local residents, raising long-term cancer risk concerns. Hydrogeological evidence demonstrates widespread groundwater contamination, aquifer vulnerability, and deterioration of potable water quality, with seasonal variability often overlooked. Methodological limitations across studies include small sample sizes, short monitoring durations, and inadequate integration of multi-hazard exposure pathways. <bold>Conclusion</bold> ASGM activities pose significant and interconnected geochemical, radiological, and hydrogeological hazards that threaten environmental sustainability and public health. The cumulative and long-term nature of these risks necessitates integrated assessment frameworks, strengthened regulatory oversight, and the implementation of sustainable mitigation strategies to protect vulnerable populations. </p>