Just how dangerous are low doses of radiation?
Mar 12, 2012, Vol. 17, No. 25 • By TOM BETHELL
After Japan’s tsunami a year ago, about 20,000 people either drowned or were lost along the country’s northeastern coast. The same tidal wave overwhelmed nuclear reactors at Fukushima Daiichi. But no ill-health effects from radiation have been reported to date.
Ahhhh: Radon springs in Misasa, Japan
Separately, a professor of toxicology at the University of Massachusetts analyzed decades-old data on the biological effects of radiation. He concluded that studies after World War II claiming that low-level radiation is hazardous were deceptive. Since the 1950s, the U.S. government has relied on these studies to argue that there is no safe level of ionizing radiation.
U.S. policy was established by the National Academy of Sciences in 1956. The risk of harm was deemed proportional to the dose. A low dose would still do some harm, in other words, and there is “no threshold” below which radiation can be considered harmless. In 1977 the National Academy of Sciences Committee on Safe Drinking Water applied the same standard to chemicals, imposing huge cleanup costs on society; for example, at “Superfund” sites.
The research on which the “no threshold” policy was based was recently challenged by Edward J.
Muller, who won the Nobel for Physiology or Medicine, had earlier shown that atomic radiation can induce mutations in fruit flies. There is no doubt that it can—if the dose is high enough. The contentious issue is whether low doses are also harmful. After months of research at the American Philosophical Society, Calabrese has concluded that U.S. radiation experiments conducted after 1945 failed to confirm that low doses are hazardous.
A test in 1946 by a well-known radiation geneticist at the University of Rochester, Curt Stern, helped by one colleague and showing no safe dose, was contradicted by a later and better-designed test, also by Stern but with a different colleague. The later test showed a “threshold” below which no effects are seen. The second test used effective dose levels that were far lower, but still well above normal background radiation levels.
Muller knew that the latter result had contradicted the earlier one: But as though nothing had happened, he said in his Nobel lecture that there was “no escape from the conclusion that there is no threshold.” No safe level, in short. Both studies were later published in the journal Genetics, then edited by Curt Stern. But a key sentence published earlier, noting “the possibility of a tolerance dose for radiation,” was omitted.
In the Proceedings of the National Academy of Sciences last December, Calabrese wrote that the U.S. government’s “no threshold model” for the assessment of risk became the regulatory standard “as a result of ideological motivations and manipulations of the scientific literature at the highest possible level.” He was referring to Muller’s Nobel speech.
As to his political views, Muller was employed as a geneticist in the Soviet Union from 1933 to 1937. The experience is said to have cured him of his earlier Communist sympathies, but he remained a socialist. Elof Carlson’s biography of Muller notes that from the mid 1950s, Muller “favored a cessation of nuclear tests as a step to disarmament.”
In an email to me, Calabrese wrote that he has received some criticism for his remarks on Muller, but his critics “have not been able to attack any factual basis.”
For years, Calabrese has argued that low-level radiation not only does no harm, but is actually beneficial. There is much to support that claim, and the evidence for it was favorably reviewed by Science in 2003 [v. 302,
Since the 1960s, the Atomic Bomb Disease Institute of Nagasaki University kept records of approximately 120,000 survivors of the Nagasaki bombing, comparing their health with that of matched cohorts of unexposed Japanese. Conclusion: Low doses of atomic-bomb radiation increased the lifespan of atom-bomb survivors.
The world is constantly exposed to natural radiation—from uranium in the rocks, from radon gas, and from cosmic rays from outer space. Areas of high background radiation in the United States (the Rocky Mountain plateau) have cancer rates markedly lower than areas with low background radiation (the Mississippi Valley).
With the passage of time, as the half-lives of various radiation sources dwindle away, background radiation is constantly declining. Calabrese told me that we live in a “radiation-deficit environment.”
Theodore Rockwell, who worked on the Manhattan Project at Oak Ridge and was hired by Admiral Hyman Rickover to work on the Naval Nuclear Propulsion program in the 1950s, says that locations with high natural background radiation have levels “as much as a hundred times greater than the forbidden areas” around the Fukushima accident site in Japan.
One of these high background radiation places is Misasa Hot Springs in Japan, which advertises itself as containing “a high percentage of health-promoting radium.”
Radium emits radon, and many of the traditional European spas, celebrated since the 19th century for reducing aches and pains, correspond to what are now known to be high-radon sites. Klaus Becker, who was head of applied dosimetry at Oak Ridge National Laboratory and is now retired in Germany, told me that in Bad Gastein in Austria customers pay $550 for ten hours’ inhalation of radon at over 1,000 times the EPA-recommended level.
The irony is that the Austrian government pays for antiradon remediation measures while the public health service pays for treatment (for bursitis, rheumatic and asthmatic conditions) at the radon-rich spas.
For antinuclear activists, meanwhile, Fukushima has been the gift that keeps on giving. Germany— its reactors provide 23 percent of the country’s electricity—will phase out all nuclear power by 2022. The engineering firm Siemens will stop building nuclear plants. Italy’s plan to generate 25 percent of its electricity with nuclear power was rejected in a June referendum. Switzerland’s five nuclear reactors (yielding 40 percent of its electricity), will not be replaced at the end of their life span. Only two of Japan’s 54 reactors, which previously provided 30 percent of its electricity, are still running. Most have been shut down for safety checks, and this winter the country is facing power shortages.
Plans to start up a newly constructed nuclear reactor on the southern tip of India have been obstructed by antinuke activists, some of whom came from as far away as the United States and Australia. They effectively demonstrated that environmental activism is an indulgence of the wealthier classes. Many people are so confused that they believe an accident at a nuclear power plant could turn it into an atom bomb; antinuke activists do nothing to allay such fears.
The “no threshold” theory is also convenient for antinuclear activists because government regulations do their work for them. The government says that additional radiation will cause additional cancers—end of story. Crusading journalists have no need to delve into details about rems, sieverts, rads, and roentgens. Tokyo residents can detect “hotspots” with store-bought dosimeters, but the radiation levels are low enough to be harmless, or perhaps beneficial.
Gov. Andrew Cuomo wants to shut down the Indian Point nuclear plant 36 miles north of New York, which faces license renewal challenges. As Indian Point supplies 25 percent of the city’s electricity, it might provide a salutary lesson if Cuomo were to prevail.
Meanwhile, in France, where nuclear power provides three-fourths of the country’s electricity, there has been no retreat. President Sarkozy said that “one has no right to play up medieval fears.” Also undeterred is China, which is continuing with plans to build 36 new reactors over the next decade. Vietnam’s plan to build two reactors (with help from the laid-off Japanese reactor companies) also remains on track.
In view of the ease with which public fears can be aroused, and the huge costs involved in shutting down reactors and replacing them (as is optimistically planned in Germany) with offshore wind farms, those old experiments with irradiated fruit flies should be repeated. This time the exposure should be as low as that found near a damaged reactor.
Tom Bethell is a senior editor at the American Spectator.
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