Fact Sheet: Illegal Gold Mining in Madre de Dios, Peru

Worldwide, small‐scale mining accounts for one‐third of all mercury pollution; in Madre de Dios alone an estimated 30 to 40 tons of mercury are dumped into the environment annually. Mercury, a potent neurotoxin, is used to amalgamate gold particles and then burned off – generally without even rudimentary technology to protect workers’ health or capture waste or fumes
http://www.amazonconservation.org/pdf/gold_mining_fact_sheet.pdf