Artisanal gold mines operate in more than 55 countries, generating around a quarter of the world’s gold supply. These smaller-scale mines use rudimentary methods of extracting and processing metals.
In artisanal gold mining, most miners use mercury to isolate and transport gold. By the Environmental Protection Agency’s estimation, this practice results in the second largest source of global mercury pollution.
When mercury is mixed with silt that contains small gold particles, it binds to the gold, forming an amalgam. When this amalgam is later heated, the mercury is vaporized—leaving behind the captured gold.
Mercury fumes and mine tailings pollute the environment near artisanal mining operations, which employ some 15 million men, women, and children. By the World Bank’s estimation, it is: “a poverty driven activity, typically practiced in the poorest and most remote rural areas of a country by a largely itinerant, poorly educated populace with little other employment alternatives.”
With gold at record-high prices, artisanal mining is unlikely to ebb. Programs like the United Nation’s Global Mercury Partnership are working with mining communities to minimize mercury pollution through improved practices and alternative technologies, like low-cost centrifuges—but change has been slow.
It is hoped that reducing the amount of mercury available on the global market will help drive alternatives. Over the past several years, both the U.S. and the European Union have enacted mercury export bans. Both had been significant suppliers.
More work needs to be done. For now, gold produced by larger mines that don’t use mercury is better for all of us.
Web Links
Environmental Health Perspectives
http://ehp.niehs.nih.gov/2012/11/120-a424/
Artisanal Gold Mines
http://www.epa.gov/international/toxics/mercury/asgm.html
Human Rights Watch
http://www.hrw.org/news/2011/12/06/mali-artisanal-mines-produce-gold-child-labor
The World Bank
EPA Mercury Emissions Breakdown, Global
http://www.epa.gov/international/toxics/mercury/mercury_context.html#types
Global Mercury Partnership
http://www.unep.org/hazardoussubstances/Mercury/GlobalMercuryPartnership/tabid/1253/Default.aspx
Photo, taken on June 19, 2010, courtesy of Gabriele Battaglia via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY, with partial support from the Field Day Foundation.