mercury in artisanal and small scale gold mining

To recover the gold from the amalgam, it’s burned, which most miners do out in the open (or on their kitchen stoves), which vaporizes the mercury and releases it to the atmosphere. Apart from breathing the fumes, as mercury re-enters the environment it threatens the health of the miners, communities, wildlife and all who consume poisoned proteins. Finally, the spent ore is dumped on site or into a water body.

Mercury releases from small scale gold mining are now the second leading cause of mercury pollution on the planet, second only to the burning of fossil fuels. An estimated one third of annual mercury consumption is attributed to small scale gold mining, with an estimated 1000 tons of mercury being released into the environment annually. 
http://www.artminers.org/artminers/mercury.html