Granite Countertops Proved Safe and Pose No Radon Risk

The most comprehensive review of scientific data on radon emissions from granite countertops shows that contribution to indoor radon levels is well below EPA's guideline for action and even levels found in outdoor air.

The study reviewed more than 500 measurements of radon emissions from granite published in peer-reviewed scientific journals. It showed that the average granite slab contributes to indoor radon levels that are:

• 300 times lower than levels of radon in outdoor air,
• 1,000 times below the average concentration of radon found in the air of U.S. homes, and
• 3,000 times less than the action level for indoor air recommended by the U.S. Environmental Protection Agency (EPA).

"We reviewed data reported by every peer-reviewed, published study we could find and the conclusion is clear: No scientific evidence exists to suggest that granite countertops are a source of meaningful exposure to radon," said Dr. John F. McCarthy, president of Environmental Health & Engineering, a consulting firm specializing in indoor environmental exposure assessments, which conducted the analysis. "To be clear, the numbers came from scientific studies that were reviewed by other scientists, which meet a much higher standard for accuracy than the data commonly reported in popular media."

"In considering the public's health, we ask an important question -- how much do natural stone countertops contribute to the amount of radon inside U.S. homes?" McCarthy asked. "The answer is very little, according to the best scientific evidence that is available at this time."

The analysis took the published radon measurements and assessed the impact they would have on radon levels present in the typical home. The findings showed that the average stone would contribute barely measurable amounts of radon. Even the highest emitting stones in the most tightly constructed home would still lead to radon levels 70 times lower than EPA action levels.

"This study is consistent with all the studies we've conducted in the past, which have found that granite countertops pose no health risk," said Jim Hogan, president of the Marble Institute of America, the nation's leading natural stone trade association, which has funded several independent scientific analyses of granite countertops. "Though media reports have created public concerns about the safety of granite countertops, science continues to show that those reports have no basis in fact."

Following recent media reports that granite countertops may be dangerous, a growing body of scientific opinion has reaffirmed that no corroborated scientific research suggests that granite countertops pose any significant health risk. Scientific authorities and public agencies that have vouched for the safety of granite countertops include:

• The American Association of Radon Scientists and Technologists (AARST), whose members are experts in the field of radon testing and research.
• Health Physics Society (HPS), a scientific and professional organization whose members specialize in occupational and environmental radiation safety.
• Dr. L.L. Chyi, professor of geochemistry and environmental geology at the Department of Geology and Environmental Science, University of Akron.
• The Florida Department of Health, whose own tests of granite show the stone poses no risk.
• The Texas Department of State Health Services, which has explicitly said consumers are more threatened by background levels of radiation than by granite countertops.
• The North Carolina Geological Survey, which dismisses granite-based health risk.
• Washington State Department of Health, which said the radon issue should not be the "deciding factor on whether or not to get granite countertops."
• The U.S. Environmental Protection Agency, which recently updated its position on granite countertops: "Based on existing studies, most types of granite used in countertops and other aspects of home construction are not typically known to be major contributors of radiation and radon in the average home."

A copy of the complete study, including citations of all peer-reviewed scientific journals it analyzed, can be downloaded either through the Marble Institute of America at http://www.marble-institute.com/industryresources/countertops_radon_wp.pdf or through the Environmental Health & Engineering website, at http://www.eheinc.com/stonecountertops.htm.