A new technology from Japan could be the key to cleaning up mercury pollution caused by centuries of gold mining, reports Foreign Confidential editor-at-large André Pachter.
Gold mining is "the surprising source of most mercury pollution," as Douglas Main recently noted in LiveScience, followed by burning coal to produce electric power.
And, despite international efforts to deal with mercury--click here to read about the Minamata Treaty and here to read about Minamata Disease--there has not been a practical solution to the problem that is poisoning the planet and is especially acute in Peru and other developing countries, where artisanal and small-scale gold miners use mercury to extract the precious metal. The miners isolate gold by mixing mercury with ores dug from the ground or from stream beds. The mixing forms an amalgam. When the amalgam is burned, the elemental mercury vaporizes into a toxic plume that leaves the gold behind.
Since gold mines are almost always set up near rivers, excess chemicals are often distributed directly into waterways.
A solution seems to be in sight, however. Foreign Confidential has learned that a promising new technology developed in Japan to treat toxic heavy metals found in coal ash, such as arsenic, lead, selenium, and hexavalent chromium--all of which cause increased risk of cancer, learning disabilities, neurological disorders, birth defects, reproductive failure, asthma, and other illnesses--could also be used to clean up the mercury morass. Foreign experts have shown serious interest in the waste treatment technology; and commercialization agreements are said to be in various stages of development.
In addition to gold mines and coal-fired electric utilities, mercury pollution sources include bleaching of paper and textiles, bleach production, and agricultural pesticides.
Mercury that is released into the atmosphere by coal-fired power plants or into rivers by gold miners is converted by bacteria into methylmercury, which gets bio-accumulated in the food chain.
High levels of mercury contamination can cause birth defects and brain damage.