A REPORT in the New York Timeslast week suggesting that granite countertops in people's kitchens represent a radon hazard has been played down by the Radiological Protection Institute of Ireland (RPII).
The report, What's Lurking in Your Countertop?, said that the US environmental protection agency had been receiving more calls in recent months from radon inspectors about granite countertops with high levels of the cancer-causing radiation.
It cited one routine inspection at a house at Lake George, New York, which found its granite countertops were emitting radiation at levels 10 times higher than those measured elsewhere - including the basement.
Stanley Liebert, of New York-based CMT Laboratories, who used a Geiger counter to take the measurements, told the newspaper: "It's not that all granite is dangerous. But I've seen a few that might heat up your Cheerios a little."
The report noted that while there have been more reports of "hot" or potentially hazardous countertops, health physicists and radiation experts agree that most granite countertops emit radon gas at extremely low levels compared with background radiation or X-rays, luminous watches and smoke detectors.
Dr Tony Colgan, the RPII's director of advisory services, agreed that granite "would naturally have a higher uranium level than other building materials, such as concrete blocks, plasterboard or paint".
But he said he "wouldn't be really concerned about it".
He noted the rock beneath a house was the main source rather than building materials or countertops. "I haven't seen this in any scientific paper," he said.
According to the New York Times, research scientists at Rice University in Houston, Texas, found that a "handful" of 55 samples of granite countertops had levels 100 times or more above background radiation.
"Allegations that granite countertops may emit dangerous levels of radon and radiation have been raised periodically over the past decade, mostly by makers and distributors of competing countertop materials," the newspaper claimed.
"The Marble Institute of America has said such claims are 'ludicrous' because although granite is known to contain uranium and other radioactive materials like thorium and potassium, the amounts in countertops are not enough to pose a health threat."