Q: I recently read in a magazine article that granite countertops emit radon gas. Is that true? I have granite countertops in my house; should I be worried?
Heather P., Greenville, SC
A: It is true that some radon gas is emitted from granite countertops. Radon is a byproduct of the decomposition of uranium, and uranium and granite tend to be closely associated. The actual threat to your health, however, must be put into perspective.
Radon occurs naturally in our environment, but in dilute amounts. It becomes a health concern when it becomes concentrated inside our homes. It's the exposure to these elevated levels that can contribute to lung cancer. Awareness of the role that radon plays in lung cancer has greatly increased in recent years, and it's commonly considered to be the greatest contributing factor in lung cancer among non-smokers.
At this year's annual symposium of the American Association of Radon Technologists and Scientists, several papers were presented on the topic of radon risk from granite countertops in the home. The general consensus of opinion was that yes, there is some radon gas given off by granite countertops. The total amount contributed to an average volume of indoor air, however, is relatively insignificant. In other words, those with granite countertops need not be alarmed and can breathe comfortably. What does need to be tested is average indoor air exposure--which can be tested with a standard short-term or long-term radon test--with an understanding...