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What’s Called For Is A Grain Of Salt

Thu., Aug. 14, 1997

For more than a decade, the U.S. Environmental Protection Agency has proclaimed radon a potent carcinogen that causes between 7,000 and 30,000 lung cancer deaths yearly.

Extrapolating from past studies of uranium miners, the agency has insisted that radon poses a widespread domestic menace.

The EPA has relied on an alarmist methodology that ignores the distinction between low residential and high occupational exposures, and it has clung like a barnacle to the “linear no-threshold” theory - that is, the theory that any level of radon is a dangerous level of radon. Regrettably, it has ignored emerging evidence that its understanding of radon toxicity is fundamentally mistaken.

Radon is an innocuous element. Colorless, odorless and tasteless, it escapes constantly into the atmosphere. It is produced by a nuclear-decay chain that starts with the uranium in rocks and soil present virtually everywhere in the United States.

Radon is part of the air we breathe, an unavoidable element of omnipresent background radiation.

Radon has elicited an intense reaction because it is radioactive.

The gas is unstable, decomposing shortly after it appears but rarely causing lung damage because it is exhaled before it decays. It gives rise, however, to short-lived “daughters” whose swift decay releases radioactivity.

Lodged in the lungs, radon’s progeny again decay, irradiating surrounding tissue, possibly causing cell damage and setting the stage for lung cancer, or so the EPA has claimed.

Radon fear originated after the post-World War II period, as the feverish search for uranium expanded mining on the Colorado Plateau. Working in dusty, dirty “dog holes,” miners were exposed to high levels of radon. Most of the miners smoked, which increased their risk.

Meanwhile, studies in Europe and the United States confirmed that prolonged exposure to radon caused lung cancer. In the 1960s, the U.S. Health Service limited miners’ occupational exposure to the gas.

Radon remained a concern of the Western states, however, until the day in 1984 when Stanley Watras, an engineer, set off a radiation detection device on his way into a nuclear plant under construction in Pennsylvania.

It turned out that his house had a radon level 16 times that permitted uranium miners. It also turned out that his house was sitting atop an abandoned uranium mine. Suddenly, radon became a household threat nationwide.

Using the lung cancer rates of the highly exposed miners as a standard, EPA asserted that radon in homes posed an equivalent risk, despite the different levels and conditions.

To avert the dire threat of lung cancer, the EPA declared that every home in the country should be inspected and the danger mitigated if testing showed an “action level” of radon.

Testing would cost an estimated $10 billion to $20 billion, and remediation of “unsafe levels,” from $50 billion to $1 trillion.

Congress went further. The Indoor Radon Abatement Act of 1988 enunciated as a national goal that the air within buildings “should be as free of radon as the ambient air outside of buildings.”

This was science-free analysis. The pressure differentials of manmade constructions suck in soil gases, so radon levels inside buildings will always be higher.

The cost of sealing cracks in the basement and installing a ventilating system runs between $300 and $2,500, and can soar. Happily for their wallets, Americans have remained largely apathetic.

Frustrated, the EPA has instituted a campaign of toxic terror. Billboards in the Washington subway scream, “Call 1-800-RADON.”

A television spot depicted a family gathering at which the children, exposed to radon, turned into skeletons.

That tactic backfired: The ad created such protest that it was canceled.

In the rush for testing and remediation, the role of smoking is often overlooked. The EPA does note that smokers have a higher risk of radon-induced cancer than do nonsmokers, but it fails to observe that smoking multiplies the risk rather than simply adding to it.

Changing one’s lifestyle could bring greater benefits than the agency’s expensive strategies.

Smoking aside, several analyses suggest that the risk fails to warrant the EPA’s massive campaign.

A Finnish case-control study, published in 1996, tracked a cohort of Finns for nearly 20 years, adjusted for smoking, and concluded that there was no increased risk of lung cancer from exposure to indoor radon.

University of Pittsburgh Professor Bernard Cohen has demonstrated that the linear no-threshold theory grossly overestimates the risk from low-level radiation.

Data on about 90 percent of the U.S. population compiled from 1,729 U.S. counties show that low-dose radiation stimulates the immune system and suggests that it may actually protect against cancer.

More striking, Professor Cohen’s results suggest an inverse relationship between radon and lung cancer.

With or without correction for the prevalence of smoking, he notes “a statistically indisputable tendency for lung cancer rates to decrease with increasing radon level.”

The EPA has stolidly refused to acknowledge that evidence. Ironically, its insistence on absolute safety may be harmful.


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