Radon is a colorless, odorless and tasteless radioactive gas that occurs naturally in most rocks and soil. It is produced by the breakdown of uranium in soil, rock and water. Radon is harmlessly dispersed in outdoor air, but when trapped in buildings can increase the risk of lung cancer, especially at elevated levels.
In a National Health Advisory issued on January 13, 2005, U.S. Surgeon General Richard H. Carmona warned the American public about the risks of breathing indoor radon.
"Indoor radon is the second-leading cause of lung cancer in the United States and breathing it over prolonged periods can present a significant health risk to families all over the country," Dr. Carmona said. "It's important to know that this threat is completely preventable. Radon can be detected with a simple test and fixed through well-established venting techniques."
The National Health Advisory went on to say: "Radon gas in the indoor air of America's homes poses a serious health risk. More than 20,000 Americans die of radon-related lung cancer every year. Millions of homes have an elevated radon level. If you also smoke, your risk of lung cancer is much higher. Test your home for radon every two years, and retest any time you move, make structural changes to your home, or occupy a previously unused level of a house. If you have a radon level of 4 pCi/l or more, take steps to remedy the problem as soon as possible."
Radon is not known to cause other illnesses or problems such as upper respiratory infections, colds or allergic reactions. Its only known health effect is an increased risk of developing lung cancer. However, as with those who smoke, not everyone exposed to high levels of radon will develop lung cancer, and the time between exposure and the onset of cancer may be many years.
To protect you and your family, download and read A Citizen's Guide To Radon: The Guide To Protecting Yourself And Your Family From Radon.
Page last updated: December 27, 2019