What is Radon?

Radon is...

  • A radioactive, colorless, odorless gas
  • An environmental health concern
  • A real physical health risk

Radon is a radioactive, colorless, odorless gas derived from the radioactive decay of uranium in the soil.

The United States Environmental Protection Agency (U.S. EPA) considers radon an environmental health concern because it is the second leading cause of lung cancer, surpassed only by smoking.

Radon gas decays into airborne radioactive particles that can get trapped in your lungs. As these particles decay further, they release small bursts of radioactive energy that can damage lung tissue and lead to lung cancer over the course of your lifetime.

Studies of lung cancer in underground miners prove that long-term exposure to elevated levels of radon presents a real physical health risk.

The primary risk factors for developing radon-induced lung cancer include:

  • The amount of radon in your home
  • The amount of time you spend in your home
  • Whether or not you smoke or have ever smoked

Radon contributes to thousands of lung cancer related deaths each year. In fact, radon is the second leading cause of lung cancer in the United States today, surpassed only by smoking. Many who have died from radon-induced lung cancer never heard of radon or realized they had a radon problem in their home until they had already developed advanced stages of lung cancer.

Though you can't see or smell radon, you can find out if you have a radon problem in your home by performing a simple, inexpensive test. If you find that your home has a radon problem, there are cost-effective solutions.

Radon in Your Home

Diagram: How radon enters a home
Radon occurs naturally in the soil and usually enters homes from below.

Radon moves up through the soil to the air above and enters your home through cracks, gaps, and other holes in the foundation. Your home traps the radon inside, where it can accumulate.

Every homeowner should test his/her home for radon because any home (new and old, well-sealed and drafty, with or without a basement) may contain elevated levels of radon.

According to the U.S. Environmental Protection Agency (EPA), nearly one home in fifteen in the U.S. has elevated radon levels—that is, a radon concentration above the U.S. EPA action level of 4 picocuries per liter of air (pCi/L). These homes require mitigation to reduce or eliminate the health risks associated with radon.

Radon in Your Water

If you have questions about radon in your drinking water in Illinois, you should call the IEMA Radon Hotline at 1-800-325-1245, or the EPA Safe Drinking Water Hotline at 1-800-426-4791.

Radon can also enter a home through the water supply, but in most cases this presents a much smaller health risk than radon in the air. Though not present in most municipal water supplies, radon may exist in well water. Water vapor from the shower and other household uses can release radon particles into the air. Also, research suggests that ingesting water with high radon levels may pose some health risks.

If your water comes from a well and if you've tested and detected elevated radon levels in the air, contact a laboratory that is certified to measure radiation in water to test your water supply. If your water comes from a municipal water supply and you are concerned that radon may be entering your home through the water, contact your public water supplier.

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