What is radon and why should I care?

This is an updated revision of a previously published column.

What is radon and why should I care?

Dr. Charles E. Crutchfield, III

Radon is a radioactive, tasteless, odorless and colorless gas that escapes from the ground. It can build up inside homes, especially in the winter when ventilation is limited. Almost all homes contain some radon.

Radon is strongly associated with lung cancer, the leading cause of cancer death in the United States. Radon gas is a significant, yet rarely discussed problem in Minnesota homes. Here are some facts about radon and radon exposure:

  • Every 30 minutes someone dies from radon-associated lung cancer in the United States.
  • Radon associated cancer is preventable.
  • Forty percent of homes in Minnesota have dangerously elevated levels of radon gas. The Minnesota Department of Health recommends that all Minnesota homes be checked for radon.
  • Winter is the very best time to test your home for radon gas.
  • Radon testing kits are now available for less than $10 at radon.com.
  • For those who can’t afford the kits, a grant for a limited number of free kits are available through the Crutchfield Foundation on a first-come-first-served basis by calling 651-209-3628.

Why should I care about radon?

When radon is mixed in with air and wind outdoors, it poses no health risk. When radon accumulates in an enclosed space, such as in a home, it can build up to dangerously high levels. Ongoing exposure to radon has been associated with an increased risk of lung cancer. In fact, after smoking, it is the second-leading cause of lung cancer.

What causes radon?

Radon is formed by the natural breakdown of uranium in soil, rocks and water.

The amount of radon in a home depends on:

  • The type of rocks under and around a home
  • The amount of soil around the home
  • The local weather
  • How well insulated a home is
  • How air-tight a home is
  • The integrity of the home’s foundation

How is radon diagnosed?

The only way to know if your home has high levels of radon is to test for it. The most common test kits are called alpha track system kits.

There are a variety of testing kits available online at such websites as Amazon.com. Most of the kits are used and mailed back in for analysis. The cost of the kit commonly includes the cost for the lab evaluation.

The test kit detectors should be placed in the lowest level of a home where they are easily accessible but unlikely to be disturbed. Most detectors are left in place for three months, and then you will send the detector back to the laboratory for analysis.

The highest levels of radon are most commonly found in basements, so that’s an especially important area to test, as well as any other areas where you may have poor ventilation. Winter is an excellent time to test because it’s indicative of normal conditions in your home when your windows are closed.

Can radon exposure be prevented or corrected?

When purchasing a home, make sure you get a full radon test report on that home. Radon reports are becoming required by law in many states. If you have a home that has tested positive for unacceptably high levels of radon, many times the fix can be as simple as ensuring that major entry routes are closed off. This includes covering any exposed soil in crawl spaces and ensuring that any foundation floor cracks are completely sealed.

Sometimes a professional may be required to correct a high radon level problem, and most reputable contractors are experienced in correcting such problems. Just make sure you hire someone with experience and a good reputation. Consumer resources such as Angie’s List, or some of the sources listed at the end of this article, or even the good folks working at your local hardware store, can help with such references.

Action steps

The only way to know if your home has high levels of radon is to test for it. We take safety precautions every day. We wear seat belts, test our homes for carbon monoxide, use smoke and fire detectors and alarms, and use security systems. It’s time for all Americans to add radon detection to our normal, regular safety checklist and take corrective action if the radon levels are found to be high.

Radon levels in homes can be reduced by a certified radon mitigation specialist. A list of these specialists can be found at www.mn.radon.com.

Sources for additional information

  • Minnesota Department of Health website: health.state.mn.us/divs/eh/indoorair/radon/index.html
  • 1-800-SOS-RADON (1-800-767-7236):National Radon Hotline. Purchase radon test kits by phone.
  • 1-800-55RADON (1-800-557-2366):National Radon Helpline. Get live help for your radon questions.
  • 1-800-644-6999:National Radon Fix-It Line for general information on fixing or reducing the radon level in your home.
  • 1-800-426-4791:Safe Drinking Water Hotline, operated under contract to EPA. For information on testing, treatment, radon in water, and drinking water standards.
  • Or visit epa.gov/radon/pubs/citguide.html.


Charles E. Crutchfield III, MD is a board-certified dermatologist and Clinical Professor of Dermatology at the University of Minnesota Medical School. He also has a private practice in Eagan, MN. He has been selected as one of the top 10 dermatologists in the United States by Black Enterprise magazine and one of the top 21 African American physicians in the U.S. by the Atlanta Post. Dr. Crutchfield is an active member of the Minnesota Association of Black Physicians, MABP.org.