Homeowners should test their homes for radon, advise the Environmental Protection Agency (EPA), the American Lung Association, and other health organizations. Radon, a chemical element, is an invisible, odorless, radioactive gas found in rocks, soil, and water. It seeps into buildings through cracks and holes in floors, walls, and foundations as well as through building joints. The gas also can be released from building material or from well water. It is found in all 50 states, and about one in every 15 U.S. homes has elevated levels (depending on local geology and building construction).
Radon (and its decay products) is the second leading cause of lung cancer after smoking, accounting for 21,000 lung cancer deaths in the U.S. every year, according to EPA estimates. People who smoke and are exposed to radon have the highest risk of developing lung cancer, but it is also the leading cause of lung cancer among nonsmokers, each year killing about 2,900 Americans who never smoked. Because of the interaction between smoking and radon exposure, the best way to prevent lung cancer caused by radon is for smokers to quit smoking.
Radon exists in the air at very low levels outdoors, and virtually everyone breathes in some radon every day. The link between radon and cancer was first discovered after studies showed that underground uranium miners who had been exposed to it had higher rates of lung cancer deaths.
What you should do
Since you can’t see, smell, or taste radon, testing is the only way to know if your home has high levels. Tests that measure average concentration for more than 90 days are considered the best, because radon levels can vary from day to day or from month to month. The test should be done in the basement (or first floor, if there’s no basement), where radon levels tend to be highest.
Simple do-it-yourself test kits are available at hardware and home improvement stores. The National Radon Program Services at Kansas State University sells kits—$15 for a short-term (2 to 4 days) test kit, $25 for a long-term kit (3 to 12 months)—online, or you can order them by calling 800-SOS-RADON (767-7236). After using it, you mail in the kit for analysis and can access the results online.
While there is no safe level of radon, a result over 4 should prompt remedial action. Even if all your neighbors have had their homes tested and found no problems, you should still have your home tested. That’s because the radon risk for your house is specific to its structure, building materials, and the soil under and around it—and no two houses are precisely the same.
Radon problems can be fixed by installing special ventilation systems and sealing foundation cracks. For more information, including a free “Citizen’s Guide to Radon,” “Consumer’s Guide to Radon Reduction: How to Fix Your Home,” and “Home Buyer’s and Seller’s Guide to Radon,” as well as a color-coded national radon map, visit epa.gov/radon. Or call the National Radon Helpline at 800-55RADON (557-2366).
This article first appeared in the UC Berkeley Wellness Letter.
Also see 13 Ways to Cut Cancer Risk.