United Nations Report of the Special Rapporteur on the human rights obligations related to environmentally sound management and disposal of hazardous substances and waste

The methods of primary concern for the scope of thisreport are the chemical processes involving cyanide leaching and mercury amalgamation.The predominant method used to beneficiate gold ore and other metals is cyanide leaching.This technique uses aqueous solutions of sodium or potassium cyanide as leaching agents(lixiviants) to extract the desired metal from the ore. In the amalgamation of gold, metallicgold is wetted with mercury to form a solution of gold in mercury. The amalgam is later roasted in open air, releasing elemental mercury emissions into the atmosphere. Artisanaland small-scale gold mining (ASGM or ASM), supplying an estimated 13 per cent of theworld gold production, is the largest demand sector for mercury globally
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