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What is it?

Radon is a radioactive, extremely toxic gas that is formed naturally from the decay of uranium or thorium in rocks and soil. It is more common in some areas of the country than others.

Radon comes in air through cracks and gaps in buildings and homes.

Radon levels may be used to predict earthquakes, study atmospheric transport, and explore for petroleum and uranium.

See also: Air Pollution Mines Homes Uranium Tailings Cancer

Where is Radon found?

  • Air – indoors and outdoors
  • Water – contaminated surface, well, and groundwater

How can I be exposed to Radon?

Radon commonly enter(s) the body through:

Ingestion (swallowing)
  • Drinking contaminated water
Inhalation (breathing)
  • Indoor or outdoor air, as gas or particles attached to dust

What happens when I am exposed to Radon?

Exposure to radon can cause:

  • Lung cancer
  • Emphysema
  • Damage to lung tissue

Who is at risk for exposure to Radon?

  • Cigarette smokers
    • Cigarette smokers have an increased chance of developing lung cancer.
  • Residents of areas rich in uranium or thorium 
    • More radon will be released by rocks and soil.

Reduce your risk

If you think your health has been affected by exposure to radon, contact your health care professional. 

Always wash your hands thoroughly after handling chemicals. For poisoning emergencies or questions about possible poisons, please contact your local poison control center at 1-800-222-1222.

  • Do you live in an area where the amount of uranium and thorium is high?
  • Have you tested your home for radon levels?
  • Do you use well water?
  • Visit the EPA web page on how to find a radon test kit and mitigation professional:
  • Test radon levels in your home with a professional radon test kit.
  • If radon levels are high, contact a professional radon mitigation firm that will seal the pathways where radon can enter the building, and install a ventilation system that routes air from underneath the home to the outdoors.
  • Contact your state radon office or a nationally certified professional radon testing and mitigation firm: American Association of Radon Scientists and Technologists, and National Radon Safety Board.
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