Mercury mitigation and unintended consequences in artisanal and small-scale gold mining

The increased research attention on estimating the global mercury use and emissions in artisanal and small-scale gold mining (ASGM) has improved awareness of the problems associated with ASGM. However, little attention has been paid to the specific effects of particular intervention strategies to mitigate global mercury use and emissions in accordance with the Minamata Convention on Mercury. In this study, we examine the effect of each type of intervention (concentrate amalgamation, use of a retort, and the cyanidation technique). The results show that, despite the massive reduction in mercury emissions associated with the implementation of the retort and cyanidation technique, these interventions created new critical issues. As unintended outcome of these in-terventions, there has been a significant increase in the quantity of global mercury which needs to be properly and permanently managed as a waste (< 1740 Mg in 2050) and also in global hydrogen cyanide emissions (< 46,700 Mg in 2050). The findings of this study indicate that, when taking these measures alone, efforts to mitigate mercury use and emissions in accordance with the Minamata Convention on Mercury generate different risks which, in effect, jeopardize sustainability in ASGM. Comprehensive mercury mitigation strategies which also consider these unintended consequences should be included in the action plans adopted by policymakers at the national level.