Cyanidation of Mercury-Contaminated Tailings: Potential Health Effects and Environmental Justice
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There is a variety of health and environmental issues associated with artisanal and small-scale gold mining (ASGM), which includes concerns regarding mercury pollution. In many countries, intervention programs and policies emphasized the importance of reducing mercury use by focusing on viable alternative methods to amalgamation that may include a transition to cyanidation. ASGM communities that now employ a combination of both methods may be increasing health and environmental risks by using mercury-contaminated tailings in the cyanidation process. This review provides a current overview of mercury and cyanide use in ASGM including the dangers of centralized processing centers that lack best practices. The combination of amalgamation and cyanidation has the potential to adversely affect many ASGM communities around the world and necessitates additional investigations to determine environmental and health impacts.
KeywordsArtisanal and small-scale gold mining Mercury Amalgamation Cyanidation
The authors acknowledge the following support: UNIDO Project No.100271. We also thank Bruce G. Marshall for helpful comments and suggestions on the manuscript.
Compliance with Ethical Standards
Conflict of Interest
Kevin Drace, Adam M. Kiefer, and Marcello M. Veiga declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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