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It’s Radon Action Month

Photo: A family in sitting in front of their house.
Radon is a naturally occurring, colorless, odorless gas created by the radioactive decay of uranium. Radon can be found in many homes and work places. Breathing high levels of the gas has been linked to lung cancer.

Prolonged exposure to radon, a radioactive gas, has been recognized as a public health risk since the 1980s.

Radon is a colorless, odorless gas formed when uranium breaks down into radium and other elements. Small amounts of uranium are naturally found in most rocks and soils, although it is more common in some type of rock than in others. Uranium is a radioactive element, which means it is unstable and decays naturally into other elements. The radium formed when uranium decays is also radioactive and decays to form radon, a radioactive gas.

When radon gas is inhaled it can damage lungs. High levels of radon exposure have been linked to an increased risk of lung cancer.

Radon enters the environment from the soil, from uranium and phosphate mines, and from coal combustion. Radon exposure poses a particular health risk to several groups of people. Tobacco smokers who are also exposed to radon have especially high chances of developing lung cancer. Uranium and phosphate miners have high levels of occupational exposure to radon. Generally, many population groups are unaware of the dangers of radon gas.

Radon has been recognized as a public health risk since the 1980s, but many homes and work settings still have not been tested to see if radon exists in high enough concentrations to require monitoring or mitigation. The United States Environmental Protection Agency has set an action level of 4 picoCuries per liter of air (pCi/l). If testing shows levels higher than 4 pCi/l, home and business owners should take action, such as sealing or venting basements, to help lower radon levels in the structure. The levels should also be monitored to confirm radon levels lessen.

Testing for Radon

Many kinds of low-cost "do-it-yourself" radon test kits are available through the mail and in hardware stores and other retail outlets. Trained testing contractors are also available for hire. Contact your state radon office for a list of certified radon testers in your area. Also refer to the US Environmental Protection Agency's "Consumer's Guide to Radon Reduction" for ways to reduce radon in your home.

Radon Exposure

Potentially harmful radon exposure can occur in several settings. Any indoor space can contain radon gas particles. They may seep into the building through the foundation from the rocks and soil below. In an enclosed space such as a house, radon can build up in heavier concentrations than it would outdoors and may reach harmful levels.

Persons can also be exposed to unsafe levels of radon on the job if they work at occupations such as uranium or phosphate mining.

For More Information


Page last reviewed: January 28, 2008
Page last updated: January 28, 2008
Content source: National Center for Environmental Health
Content owner: National Center for Health Marketing
URL for this page: www.cdc.gov/Features/RadonAwareness


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