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What is it and where is it found?

Mercury is a natural rock found in the earth’s crust. This rock or ore is mined, crushed and heated to release vapors. The vapors are are condensed and collected as a liquid. The liquid is shiny, silver and odorless. It continually emits vapors when exposed to air and when heated it becomes a colorless, odorless gas. Mercury also gets into the environment from coal-fired power plants, cement plants and certain other industries, where it is discharged from smoke stacks into the air. The mercury contamination gets carried in the air and eventually settles down onto the land and into water bodies like lakes, rivers, streams and oceans.

How do people come into contact with it?

The main way people come into contact with mercury is by eating contaminated fish. This is because mercury that ends up in water bodies concentrates in the sediment at the bottom of rivers, streams, lakes and oceans. Once there, a biological process turns it into an especially toxic form of mercury called methyl mercury. The sediment dwelling creatures are eaten by the small fish, which in turn are eaten by bigger fish, and so on up the food chain. The longest living, top predator fish like large mouth bass, tuna, and shark, accumulate the most mercury of all.

Other sources of mercury include:

  • Mercury from dental work and medical treatments;
  • Compact Fluorescent Lightbulbs (CFLs);
  • Old mercury-containing thermometers;
  • Jobs involving the use of mercury  (dental, health services, chemical);
  • High school science labs;
  • Rituals that include mercury.

What are the health concerns?

Methyl mercury can damage the developing brain, which can lead to behavior and learning problems later in life. Young children as well as unborn and breast-fed babies are most at risk from mercury contamination. Mercury in a mother’s body passes to the fetus and can cause brain damage, mental retardation, lack of coordination, blindness, seizures, and the inability to speak. Children poisoned by mercury may develop kidney damage and problems with their nervous and digestive systems.

What can I do to protect myself, my family, or my employees?

What's being done to protect public health?

Oregon Department of Environmental Quality (DEQ) sponsors mercury clean-up and collection programs. Mercury thermometers, thermostats, and switches can be turned in at local hazardous waste collection locations and events. DEQ will pick up anything that weighs over one pound. 

Compact Fluorescent Lightbulbs (CFLs) can be recycled at local “big box” and hardware stores or hazardous waste collection sites. Businesses are required to recycle fluorescents bulbs.

Oregon schools are taking measures to eliminate mercury from their schools with the help of EPA and DEQ.

Where can I get more information?

Department of Environmental Quality, Mercury Information