It's been almost 10 years since doubts about the real dangers of radon gas began nagging Dr. William K. Grosh, then a family doctor in Akron.

"I had talked with some of our local oncologists and radiologists and was surprised to learn that in spite of high levels of radon in the Reading Prong area, there was a low level of lung cancer there," says Grosh, 81, now a Moravian Manor resident.

A new study of lung cancers in Lancaster County again has Grosh wondering if the radon scare is overblown.

Studies have repeatedly shown Lancaster County has some of the country's highest readings of radon, a naturally occurring gas found in the soil from decaying uranium.

The federal government says radon is the second-leading cause of lung cancer, after smoking, and the U.S. Environmental Protection Agency estimates about 20,000 people in the country die each year from preventable exposure to radon.

According to the state Department of Environmental Protection, 65 percent of homes tested in Lancaster County have been found with radon levels high enough that homeowners should take action to reduce them.

The average radon level in Lancaster County is more than three times higher than the level state and federal officials consider safe.

Yet, a state compilation of lung cancer deaths in Lancaster County spanning 2001-2005 — released by the Pennsylvania Department of Health — shows a lower rate of lung-cancer deaths here than nationwide.

But radon experts warn that drawing conclusions based on county data for radon is "meaningless" because of the relatively few number of cases and unknown health habits of the population.

However, Grosh, for one, thinks the statistics here and elsewhere raise doubts about the actual severity of radon as a health threat.

"It doesn't add up when you see the maps," says Grosh, who had high levels of radon cleared from his Ephrata home when he sold it seven years ago.

"I think it's a scare that has not been proven to that degree."

Turns out that Grosh — while perhaps in the minority — is not alone.

Bernard Cohen, professor emeritus of physics at the University of Pittsburgh, has been a doubting Thomas of the radon danger at lower levels of exposure for 20 years.

Cohen has long criticized the government's method of determining radon's danger: Taking the cancer rates suffered by uranium miners exposed to high levels of radon, and extrapolating from that a risk to homeowners, whose exposure is much lower.

Cohen, a physicist who is known for his longtime advocacy of nuclear power, says that his research shows that there is no evidence of harm from being exposed to radon until levels reach almost three times that of the accepted danger level.

"My research completely convinces me that the risks from low-level radon exposure has been grossly exaggerated. However, I must admit that I have not convinced the 'powers that be' of that conclusion," Cohen said in an interview.

His proof: Nationwide health studies that he says show lung cancer rates are lowest in regions of the country with the highest levels of radon in homes.

Cohen took lung cancer mortality rates in more than half of all U.S. counties, compared them to radon exposures and adjusted for more than 500 possible confounding factors, including smoking, geography and race.

The results, he says, show that the risk of cancer from low levels of radon is "grossly over-estimated."

Cohen also criticizes the government's use of linear no-threshold reasoning, or LNT. Such reasoning assumes that because a cancer risk has been demonstrated at a high level of exposure, those exposed to low levels are also at risk.

"Beyond failure of the LNT, there is substantial evidence that low-level radiation may be PROTECTIVE against cancer," he wrote in a 2002 paper published in the American Journal of Roentgenology.

"This means that the cancer risk from the vast majority of normally encountered radiation exposures is much lower than given by usual estimates, and may well be zero or negative," Cohen wrote in the paper.

Rubbish, say a host of other scientists involved in radon research.

"Not only is Cohen in the minority on this, but it has been rejected by those who had previously believed what Bernie said was correct," says Jay Lubin, senior investigator at the National Cancer Institute's Division of Cancer Epidemiology and Genetics.

Lubin says the National Council on Radiation Protection and Measurements organized a committee to analyze Cohen's data. "They also came to the conclusion that his approach is really without validity," according to Lubin, who says that using county-level data can't be done accurately because there are too many unknowns about the residents studied.

"On the other hand," Lubin continues, "there have been over two dozen studies of residential radon exposure and lung cancer. Virtually all these studies have found higher lung cancer rates with those higher residential radon levels.

"Moreover, the estimates they found are virtually identical from extrapolations based on models developed among underground miners."

That includes substantial risks of developing lung cancer even at low levels of radon, Lubin says, adding that as many as one-third of all radon-caused lung cancer deaths may come from long-term exposure to low levels.

Exposure from radon, he stresses, is cumulative.

Unfortunately, there is no signature for lung cancer caused by radon, Lubin says, referring to the difficulty in proving the sources of some lung cancers. In addition to smoking and radon, lung cancer can be caused by asbestos, diesel exhaust, arsenic in the air and other occupational and environmental causes.

As for Cohen's statement that low levels of radon might actually ward off lung cancer, Lubin said animal studies indicate that alpha radiation may indeed prime cells against cancer, but that doesn't occur with radiation from radon.

Lubin's criticisms of Cohen's approach of pairing up county cancer rates and radon levels are echoed by Kevin Stewart, a Lancaster County resident and the American Lung Association's director of environmental health for the Mid-Atlantic region.

"Ecological studies have been deemed inappropriate by scientists many years ago. You've got to follow people and their lifetime histories, rather than geographic areas," he said.

Elizabeth Hoffmann is a Wisconsin woman who is sure she developed lung cancer from higher-than-accepted levels of radon found in her home. She formed an advocacy group, Cancer Survivors Against Radon, to convince homeowners everywhere to test for radon and to put a human face on radon.

She says that attempts to compare lung cancer rates with radon levels are bound to be faulty. "One thing is that it can take years for lung cancer to be found. People move, not everyone exposed gets lung cancer, radon is not mentioned with smokers with lung cancer, et cetera."

When Dr. Randall A. Oyer, program director of oncology at Lancaster General Hospital, moved to Lancaster city a couple of years ago, tests showed that his home had radon levels just above normal.

He was advised he could leave windows open regularly and check levels again the following year.

But he decided to pay to have radon blown out of his home.

"Over the years, I've seen many more people with lung cancer who didn't smoke or weren't exposed to second-hand smoke in the workplace. I considered radon as one of the possible (causes) of their lung cancer."

Still, Oyer thinks a disproportionate amount of emphasis is put on radon prevention when campaigns against the dangers of cigarette smoking and testing for early signs of colon cancer would benefit a greater number of people.

Hoffmann, though, thinks the choices are clear enough.

"What I don't understand," she says, "is that radon is a known carcinogen and Lancaster is high for radon and the tests are easy, inexpensive and mitigation is also relatively low-cost.

"Why not be safe? It's too late to do anything once the doctor says, 'You have cancer.'"


Staff writer Ad Crable can be reached at acrable@LNPnews.com or 481-6029.