Review of pollution trends and impacts in artisanal and small-scale gold mining in Sub-Saharan Africa: Advancing towards sustainable practices through equitable redistribution of gold spin-offs

The use of mercury, often combined with cyanide, is common in gold processing at artisanal and small-scale mining (ASGM) sites in sub-Saharan Africa (SSA). These methods cause severe chemical pollution, harming the environment, wildlife, and human health. This article provides an overview of the trends and impacts of chemical pollution from ASGM in SSA, analyzes the underlying causes of the persistence of polluting practices and proposes mitigation strategies for more sustainable processing. Methodology involved reviewing and synthesizing 167 relevant publications from 1995 to 2024. The results show significant trends of chemical pollution and associated impacts due to the expansion and intensification of ASGM activities. The highest levels of mercury pollution in mining soils are observed in West Africa-a region with a long history of ASGM-particularly in Burkina Faso (185.94 mg/kg) and Ghana (71 mg/kg). Aquatic ecosystems exhibit similar levels of pollution, with the highest value measured in Uganda (1.21 mg/L). The analysis reveals that the underlying causes of the persistence of polluting practices at ASGM sites are primarily due to a conflict of interest in the redistribution of gold spin-offs among key stakeholders, including the state, local holders, and artisanal miners. Major points of conflict include ownership of gold resources, accessibility, distribution of gains, gold purchasing rights, tax obligations, and responsibility for supervising activities and pollution management. This study demonstrates that a more equitable approach that considers the interests of each stakeholder could create synergy in the supervision and regulation of the activity, promoting its sustainability. The strategies employed by stakeholders to maximize their gold profits and the corrective proposals for a fair redistribution of gold spin-offs are highlighted through graphical summaries. The study also notes that promoting mercury-free processing technologies is a promising alternative towards which the ASGM industry should aim. However, the challenge lies in the accessibility of the technology and its potential to increase miners' incomes for widespread adoption. The findings suggest that ASGM stakeholders in gold-producing countries of SSA should adopt an inclusive governance approach to extractive activities and ensure equitable redistribution of its spin-offs to promote a more environmentally friendly ASGM.