Granite Countertops and Radiation
Recent news stories have raised concerns about the possibility of radiation coming from granite countertops.
Granite, as with other kinds of rocks and soils, contains some naturally occurring radioactive elements commonly referred to as Naturally Occurring Radioactive Material (NORM). NORM is made up of elements such as thorium, uranium, and potassium, which contribute to what scientists call “background” radiation. Background radiation is a combination of terrestrial and cosmic radiation that individuals are continuously exposed to as part of living on planet earth. In Alabama, on average, we receive about 250 millirem each year from these sources. A person would receive approximately 20 millirem from a routine chest x-ray.
The amount of radioactivity in most granite is quite small. While it is possible to get a measurable level of direct radiation from some granite, in general most granite emit less radiation than we are regularly exposed to from background radiation. These levels are so low that they are not harmful to human health. However a very limited number of the more exotic colors have reportedly been found with more radioactivity than desirable. The granite countertop industry is reportedly taking action to remove these from the market.
Radon is a naturally occurring radioactive gas that can be released during the decay of radioactive elements in granite countertops but more commonly it can seep into homes from underground uranium deposits, and build up to higher than normal levels inside the home. (See: What is Radon?) Most areas of Alabama are considered to be at a low or moderate risk level for excessive indoor radon levels; however we do have 15 counties that are considered high risk. (See: Alabama Radon Map), no matter where you live it is still a good idea to test, and know for sure.
The Alabama Department of Public Health, along with the U.S. Environmental Protection Agency and the U.S. Surgeon General, encourages everyone to test their home for radon. As a public service the Alabama Cooperative Extension System sells radon test kits at wholesale prices in the Extension Offices in Alabama’s high radon counties for citizens to use to test their homes. (See: Where Do I Get a Radon Test Kit?)
For more information about the possibility of radon gas coming from granite countertops, please see the EPA’s Frequently Asked Questions about this issue. Some additional information about this issue may be found on the Health Physics Society’s website.
For information on radiation surveys and general information on radon, contact Jim McNees toll-free at 1-800-582-1866 or by email. For email contact, please add "radiation surveys" or "general information" in the subject line.