Franchising and Artisanal Miners

The lack of training also leads to inefficient mining and processing practices, often resulting in poor rates of gold recovery.  For example, studies of Brazilian ASM show that miners often do not have the capacity to either concentrate or grind completely or even partially liberate the ore.   In addition, the ASM sectors’ practices for liberating and recovering gold ore contribute to a number of environmental and social ills.  In particular the extensive use of mercury and cyanide are problematic.  Mercury (and its close cousin methylmercury) creates numerous difficulties in the environment, though the environmental consequences of vaporized mercury are as yet unknown.  For humans, however, the consequences of mercury intake are well documented.  There are two ways in which mercury impacts people: inhalation of mercury vapor or intake of methylmercury through the consumption of contaminated fish.  When the amalgam is burned in the open air, without the benefit of a hood for example, it becomes available for inhalation.  Inhalation of mercury vapors causes blood mercury levels to rise and can result in such symptoms as gingivitis, exaggerated emotional responses, tremors, impaired cognitive function, and sleep disorders.^[2]  Another way in which mercury enters the environment occurs when the whole ore is amalgamated.[3]  Droplets of mercury get caught up with the tailings and enter the environment.  Once in the tailings mercury can be oxidized and methylated forming the toxic methylmercury.   Methylmercury can enter the food chain via fish where it is bio-accumulated and can later be biomagnified through predation and scavenging.   Once in the food chain mercury can find its way into humans via fish consumption.  In humans mercury accumulates in the brain causing motor neurological problems and ultimately death.
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