Mercury

Gold Mines are a Source of Mercury Air Pollution

• Gold mines are the fifth largest source of mercury air emissions in the U.S. 
• They produce fully 25% of all mercury air emissions west of Texas.
• Yet there are no federal regulations requiring gold mines to control their mercury emissions.

Ore roaster at Gold Quarry mine, NV.  Photo: EARTHWORKS

Most mercury emissions come from gold mines in northern Nevada because these mines are located in an area where gold ore also contains mercury.  The mercury is released into the air when the ore is heated during the gold extraction process.

Air emissions from these mines may travel great distances, affecting states throughout the Intermountain West.

Serious Public Health Effects
Mercury is considered the most dangerous heavy metal because it is toxic to humans and moves freely through the environment.

Mercury in the air eventually ends up in our nation's rivers and lakes, and ultimately in the fish we eat. 

There is no method of cooking or cleaning that will reduce the amount of mercury in a meal.

According to a 2005 study, between 317,000 and 637,000 children born each year in the United States are exposed in the womb to mercury levels above the Environmental Protection Agency's safety level.  Children of women exposed to relatively high levels of mercury during pregnancy show delayed onset of walking and talking, reduced neurological test scores, and delays and deficits in learning ability.  The study further states that diminished intelligence of children exposed to mercury contamination before birth costs the U.S. economy $8.7 billion a year in lost productivity.

Harm to Fish and Water Resources
Mercury in our nation's rivers, lakes and streams are a particular problem because bacteria convert mercury to methlymercury, an organic form that is toxic to living beings. 

When methylmercury enters the food chain, it becomes progressively more concentrated with each step up the food chain.  So fish at the top of the food chain -- predatory fish like bass and tuna -- can contain mercury in their muscle tissue that is much higher than the mercury concentration in the surrounding water.

In the U.S., 45 states have advised limiting fish consumption due to mercury contamination. Over 750,000 river miles and 13 million acres of freshwater lakes in the U.S. are under a fish consumption advisory for mercury.

Regulations Needed
Gold mines should be regulated, just as other large sources of mercury emissions, under the federal Clean Air Act. 

Federal regulations should be developed to ensure that public health and the environment is protected, mining companies are subject to consistent and equitable regulatory standards, and mercury emission limits are enforceable. 

For More Information

• Read the latest press release on Mercury.
   
• Read the EARTHWORKS fact sheet.
   
• Read the joint report, Three Nevada Gold Mines Grossly Under-Report Mercury Air Emissions
   
• Read the joint report, Dramatic Increases in 2005 Reported Mercury Air Emissions at Two Nevada Mines
   
• Read the Idaho Conservation League report, Mercury Pollution in Northeast Nevada Air
   
• ToxFAQs for Mercury.  Agency for Toxic Substances and Disease Registry, Centers for Disease Control and Prevention

References for this page:

U.S. Environmental Protection Agency (EPA> Toxics Release Inventory data, 2002

U.S. EPA Fact Sheet. Mercury Update:  Impact on Fish Advisories. EPA-883-F-01-011, June 2001

U.S. EPA, 2003 National Listing of Fish Advisories, August 24, 2004

"Unregulated Nevada Mines Spew Mercury," Idaho Statesman, October 30, 2004

2003 Program Summary Report to Nevada Division of Environmental Protection from Barrick Goldstrike, July 2004

Blood and Hair Mercury Levels in Young Children and Women of Childbearing Age --- United States, 1999.  As reported in MMWR Weekly, March 2, 2001, 50(08):140-3.