Artisanal Gold Mining: A Dangerous Pollution Problem

Artisanal gold mining is one of the most significant sources of mercury release into the environment in the developing world, with at least a quarter of the world's total gold supply coming from such sources[5]. Artisanal gold miners combine mercury with gold-laden silt to form a hardened amalgam that has picked up most of the gold metal from the silt. The amalgam is later heated with blow torches or over an open flame to evaporate the mercury, leaving small gold pieces. The gaseous mercury is inhaled by the miners and often by their immediate family, including their children. Mercury that is not inhaled during the burning process, settles into the surrounding environment or circulates globally for future deposition far from the site, where it is absorbed and processed by a variety of living organisms. This transforms elemental mercury into methylmercury. Methylmercury is one of the most dangerous neurotoxins that contaminate the food chain through bioaccumulation.
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