Under-Exposed: What if Radiation is Actually Good for You? by Ed Hiserodt, 247 pp, paperback, $14.95, ISBN 0930073355, Little Rock, Ark., Laissez-Faire Books, 2005.
The linear no-threshold (LNT) hypothesis for radiation carcinogenesis could be the costliest error in the history of science.
It was invented by Linus Pauling to win the debate with Edward Teller on banning atmospheric testing of nuclear weapons, according to Pauling's long-time close collaborator Arthur B. Robinson (personal communication). It uses the concept of collective dose to calculate huge numbers of casualties from tiny exposures. By the same reasoning, if 1,000 aspirin tablets will kill one man who takes them all, one death will also occur as a result of 1,000 men each taking a single aspirin.
Hiserodt demolishes the LNT in his brief, lucid book. Though written for the lay public in a chatty, coloquial style, the technical exposition is solid and footnoted, and it will not insult the intelligence of physicians.
Radiation, like many (if not most) chemicals, exhibits a biphasic dose-response curve, also called hormesis. While high doses of radiation are lethal, doses within a certain low range have a nonspecific stimulatory effect on the organism, enhancing growth, immune response, or DNA repair mechanisms.
Hiserodt reviews the most important animal and human data, with clear charts and graphs showing findings that will astonish those indoctrinated in the belief that any dose of radiation is harmful.
Among A-bomb survivors, longevity was increased at low-to-intermediate doses (1-199 rads). Mortality in Americans weapons plant workers was significantly less than expected. Nuclear shipyard workers exposed to radiation had lower all-cause and cancer mortality than their non-exposed counterparts. The actual evidence is consistent and convincing, as long as one looks at the data itself, and not the conclusion that prestigious committees draw for the abstracts.
The Environmental Protection Agency's campaign to reduce indoor radon exposure is based primarily on data from uranium miners, who do indeed have a higher risk of lung cancer. However, the potential role of other factors present in uranium mines, such as particulates and fumes from diesel engines, was never considered. The cancers are deep in the lungs, like those of South African miners exposed to amphibole-type asbestos, rather than concentrated in the bronchial epithelium as would be expected.
A multimillion-dollar, 5-year effort to demonstrate the harm caused by radon levels in homes, however, showed a highly significant protective effect. Bernard Cohen wrote: "It came as a great shock to me that my data ran contrary to LNT, and I didn't fully believe it until about 1993 - when I shut off the $1,200 radon reduction system in my house to save electricity." But it didn't make the news, and bureaucrats and health physicists - who have a vested interest in overzealous radiation protection - appear to pretend that the data either don't exist, or can be explained away. If radon were recognized as "Vitamin R," a lot of regulators would be looking for another job.
While the LNT-predicted radiation casualties are purely hypothetical, the deaths caused by belief in the LNT assumption are tragically real. After the Chernobyl accident, between 100,000 and 200,000 babies were aborted in Europe because their mothers believe they might be carrying "nuclear monsters." The actual dose from Chernobyl was about 1.4 SXR in Greece, and 0.5 in France: the SXR being a Hiserodt-coined unit for the dose received from one "shoe x-ray" in the days when good shoe stores had a fluoroscope to check the fit of the shoes. One could also receive 1.4 SXR from residing in Colorado instead of Texas for about 19 months.
Hiserodt includes a fascinating discussion of benefits that we have forgone because of misunderstanding radiation: the plutonium-powered pacemaker that never needs a battery change; a car that could conceivably get 5 million miles to the pound of plutonium; and small, intrinsically safe nuclear power generating stations. Promising medical benefits blocked by the LNT include low-dose radiation for cancer prevention, and even treatment; potential cure of rapidly lethal infections such as gangrene; and relief of conditions such as arthritis.
Reasons to keep this book on the reference shelf include its clear explanation of dose units; its tables of exposures from sources such as power reactors, your own blood, or jet flight; the specific activities of dangerous substances like salad oil and whisky; and the table on the manifestations of acute radiation syndrome. Even if you don't need the chapter on remedial nuclear physics, you'll probably learn something about what goes on in a nuclear reactor.
This is a good book to give to nervous patients, students, teachers, physics-challenged reporters and public officials. But do keep one for yourself.
Jane M. Orient, M.D.
Tucson, AZ
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