An increasing number of illegal, small-scale gold miners have been blamed by scientists for intensifying mercury pollution in Madre de Dios, a region in Peru’s southeastern Amazon Basin.
Researchers from Duke University, in North Carolina, say the upsurge in small-scale gold mining over the past 20 years has caused extensive environmental damage. Large tracts of land have been cleared, allowing the mercury used by illegal miners to erode the soil and increase environmental and human exposure to the neurotoxic substance.
Exacerbating the problem is the fact that these miners often use far more mercury than is necessary. Routinely used in the gold extraction process, mercury is burnt off and toxic gas is released into the air. Gold mining waste containing mercury also moves through the soil more quickly in cleared areas, easily making its way into nearby water sources.
“This means mining practices can hit people three times with mercury—once from direct contact, once from atmospheric transport and deposition, and once from soil mercury mobilization due to land clearing,” explains Associate Professor William Pan, who is part of a team developing a model to predict the amount of mercury being released into the ecosystem by deforestation and small-scale gold mining.
If current deforestation trends persist, scientists predict the amount of mercury released into the local river system could increase by 20 – 25% by 2030.
Clean tech clean-up
Clean Mining, a part of the Clean Earth Technologies group, is developing breakthrough technologies to eliminate mercury from the gold extraction process altogether, by replacing it with a proprietary thiosulphate-based solution. The company is also developing an innovative clean-up tool, a sulphur-based polymer, that remediates mercury pollution in its various forms—a potential lifesaver for vulnerable communities like those in Madre de Dios.
*Source: Science Daily