Granite countertops could pose a risk

Shortly before Dr. Lynn Sugarman of Teaneck, N.J., bought her summer home in Lake George, N.Y., two years ago, a routine inspection revealed it had elevated levels of radon, a radioactive gas that can cause lung cancer. So she called a radon measurement-and-mitigation technician to find the source.

"He went from room to room," said Sugarman, a pediatrician. But he stopped in the kitchen, which had richly grained cream, brown and burgundy granite countertops. His Geiger counter indicated the granite was emitting radiation at levels 10 times higher than those he had measured elsewhere in the house.

"My first thought was, my pregnant daughter was coming for the weekend," Sugarman said. When the technician told her to keep her daughter several feet from the countertops to be safe, she said, "I had them ripped out that very day," and sent to the state Department of Health for analysis.

The granite, it turned out, contained high levels of uranium, which is radioactive and releases radon gas as it decays. "The health risk to me and my family was probably small, but I felt it was an unnecessary risk," Sugarman said.

As the popularity of granite countertops has grown in the past decade — demand for them has increased tenfold, according to the Marble Institute of America, a trade group representing granite fabricators — so have the types of granite available. For example, one source, Graniteland, offers more than 900 kinds of granite from 63 countries.

"It's not that all granite is dangerous," said Stanley Liebert, quality-assurance director at CMT Laboratories in Clifton Park, N.Y., who took radiation measurements at Sugarman's house. "But I've seen a few that might heat up your Cheerios a little."

Periodic claims

Claims that granite countertops may emit dangerous levels of radon and radiation have been raised periodically, mostly by makers and distributors of competing countertop materials. The Marble Institute of America has said such claims are "ludicrous" because although granite is known to contain radioactive materials, the amounts in countertops are not enough to pose a health threat.

Health physicists and radiation experts agree that most granite countertops emit radiation and radon at extremely low levels.

They said these emissions are insignificant compared with so-called background radiation that is constantly raining down from outer space or seeping up from the earth's crust, not to mention emanating from X-rays, luminous watches and smoke detectors.

But with increasing regularity recently, the Environmental Protection Agency (EPA) has been receiving calls from radon inspectors and from homeowners about granite countertops with radiation measurements several times above background levels.

"We've been hearing from people all over the country concerned about high readings," said Lou Witt, a program analyst with the agency's Indoor Environments Division.

Recommendations

The EPA recommends taking action if radon gas levels in the home exceed 4 picocuries per liter of air (a measure of radioactive emission); about the same risk for cancer as smoking a half a pack of cigarettes a day. In Sugarman's kitchen, the readings were 100 picocuries per liter.

The average person is subjected to radiation from natural and human-made sources at an annual level of 360 millirem (a measure of energy absorbed by the body), according to government agencies such as the EPA and the Nuclear Regulatory Commission.

The limit of additional exposure set by the commission for people living near nuclear reactors is 100 millirem a year. To put this in perspective, passengers get 3 millirem of cosmic radiation on a flight from New York to Los Angeles.

A "hot" granite countertop like Sugarman's might add a fraction of a millirem per hour and that is if you were a few inches from it or touching it the entire time.

Nevertheless, Witt said, "There is no known safe level of radon or radiation." Moreover, he said, scientists agree "any exposure increases your health risk."

A granite countertop that emits an extremely high level of radiation could conceivably expose body parts that were in proximity to it for two hours a day to a localized dose of 100 millirem over a few months.

David Brenner, director of the Center for Radiological Research at Columbia University in New York, said the cancer risk from granite countertops, even those emitting radiation above background levels, is "on the order of one in a million." Being struck by lightning is more likely. Nonetheless, Brenner said, "It makes sense. If you can choose another counter that doesn't elevate your risk, however slightly, why wouldn't you?"

Radon is the second leading cause of lung cancer after smoking and is considered especially dangerous to smokers, whose lungs are already compromised. Children and developing fetuses are vulnerable to radiation, which can cause other forms of cancer. Witt said the EPA is not studying health risks associated with granite countertops because of a "lack of resources."

As for Sugarman, the contractor of the house she bought in Lake George paid for the removal of her "hot" countertops. She replaced them with another type of granite. "But I had them tested first," she said.