The toxic metal used at thousands of remote mining sites travels through the atmosphere and contaminates fish worldwide. It harms not only local workers, but people around the globe
KERENGPANGI, INDONESIA - A gold miner stands waist-deep in a polluted pond, dumps a capful of mercury into a bucket of ore and mixes it in with his bare hands.
The darting liquid metal wraps itself around the gold to form a silver pellet the size of a marble.
The use of mercury in gold mining is illegal in Indonesia because the metal is toxic to humans and the environment. But the price of gold has tripled since 2001, and mercury is the easiest way to extract it.
"Of course I'm worried," said miner Handoko, 23, a grim man in a baseball hat who goes by one name. "But this is the job."
Tens of thousands of remote mining sites have sprung up mostly in Asia, Latin America and Africa, using as much as 1,000 tons of mercury each year. The mercury ravages the nervous system of miners and their families. It also travels thousands of miles in the atmosphere, settling in oceans and riverbeds in Europe and North America and contaminating fish.
Small-scale gold mining is the second-worst source of mercury pollution in the world, after the burning of fossil fuels. And Indonesia ranks behind only China in the use of mercury in gold mining.
Mercury's impact is evident in mining regions like Central Kalimantan, on the island of Borneo. Acres of former tropical forest are now virtual desert. Villagers say fish populations have dropped by 70%. The Galangan gold mining site stretches several miles, stripped of trees and dotted with mercury-laced ponds.
"This area is finished," said Fauzi Achmad, a gold shop owner, as he drove past the moonscape-like dunes and abandoned mines.
Despite the hazards, buying mercury at gold mining sites is as easy as purchasing toothpaste. The international trade in mercury is largely unregulated. And most of the 55 countries where small-scale gold mining is rife lack the political will or capacity to prevent the metal from falling into the hands of 10 million to 15 million poor miners.
"The continued use of mercury in gold mining threatens millions of people all over the world, since mercury is a global air pollutant," said Michael Bender, a coordinator for the Zero Mercury Working Group, a coalition of 40 groups worldwide that campaigns to reduce mercury use. "We're talking about a neurotoxin that science clearly shows threatens pregnant women, their fetus and those who eat large amounts of fish."
The use of mercury in gold mining dates back thousands of years. The Romans forced slaves and criminals to extract gold and silver with mercury.
By the 20th century, mining companies had abandoned mercury in favor of chemicals like cyanide. But small-scale miners like it because it's easy to use, fast, cheap and leaves the gold cleaner than traditional panning.
"The miner cannot be separated from the mercury," said Achmad, the gold shop owner, who has campaigned to persuade miners to use less mercury. "With mercury, it makes the work fast."
Traders once relied on mercury from Spain, Algeria, China and Kyrgyzstan, but most mercury mines are now shuttered and China supplies only its own market. So mercury comes from the leftover stockpiles of closed mines or the dozens of companies in Europe and the United States that recycle the metal from old light bulbs, batteries and industrial waste, according to the United Nations and the Zero Mercury Working Group.
Flasks of mercury worth hundreds of dollars are sold into an opaque and largely unregulated network of brokers who crisscross the globe, said Peter Maxson, a Brussels-based expert on the trade. They divert mercury supplied for legal purposes to the gold mines instead, where it can fetch prices 10 times higher than on the world market, he said.
"Countries import several hundred times the mercury they need for dental and other legal uses," said Pablo Huidobro, project manager for the U.N. Industrial Development Organization's Global Mercury Project. "The excess makes its way to the miners through the black market."
Maxson and other experts said it can be almost impossible to track the liquid metal as it passes through brokers and even criminal gangs on its way to a gold mine. A flask of mercury can originate in Spain, be sold to brokers in India, go on to popular transit points such as Singapore or Vietnam and then get dumped in Indonesia.
The United States alone exported nearly 498 tons of mercury in 2007, up from 378 tons in 2006. It mostly was sent to Canada, Suriname, Hong Kong and Mexico, according to the U.S. Geological Survey.
"The whole trade has gone underground in the last five to 10 years. It's very secretive," Maxson said. "The companies dealing mercury won't tell you who their customers or even who the end users are."