In response to:
Is Britain 'Befouled'? from the November 23, 1989 issue
Is Britain 'Befouled'? from the November 23, 1989 issue
To the Editors:
In his stimulating review on nuclear pollution [NYR, November 23], M.F. Perutz presents a provocative table showing average radiation exposures to people living in the US, compared with residents of the UK. The bottom line, as presented by Perutz, is that UK residents would expect to receive about 50 percent less radiation dose as compared with Americans. Before the British embassy is flooded with visa applications, it is well to point out, as is so often the case with “scientific statistics,” that the difference is probably illusory.
The difference in the Perutz table primarily stems from the much larger radiation dose attributed to radon in the US compared to the UK (Radon is a naturally-occurring radioactive gas, which seeps up into houses from the rocks and soil underneath.) However the estimates of the radiation doses caused by radon in the US and in the UK are derived from significantly different types of surveys: The UK estimate, by their Radiological Protection Board, was based on a recent survey of British houses, measuring radon levels in living rooms and bedrooms. On the other hand, the US estimate, from the National Council on Radiation Protection, was primarily based—in the regrettable absence of a reliable large-scale American study—on a large Canadian survey taken in 1980. However, in this Canadian study, the preferred room for the radon measurement was the basement. Of course, because radon comes out of the ground, basement radon levels are almost always the highest in the house—usually about twice as high as in the other rooms. When this difference is taken into account, the radiation doses caused by radon to residents of the two countries are probably indistinguishable.
Incidentally, the other (much smaller) difference shown in the Perutz table between radiation doses to residents in the UK and the US is due to medically-related exposures, mainly x rays. This difference certainly is real: there are about eighty diagnostic x ray examinations in the US each year for every one hundred people; the corresponding number in the UK is about fifty. Whether the US is too high or the UK is too low is open to debate….
David J. Brenner, Ph. D.
Center for Radiological Research
Department of Radiation Oncology
College of Physicians and Surgeons
Columbia University, New York City
Exact comparisons of radon levels in British and American houses are difficult, because they are built differently. American and Canadian houses generally have basements, but all except the newest British houses merely have an empty space about two feet deep underneath the wooden floorboards of the living rooms, through which radon could easily diffuse. That empty space is connected to the outside by a few perforated bricks that are supposed to let the damp out, but are too small to provide effective ventilation. The radon levels in the living room of a typical British house may therefore be more or less equivalent to those in the basement rooms of a typical American house, except that they would be better ventilated, at least in summer. In Britain areas with high radon emission, like Cornwall and Scotland, tend to be thinly populated, but this is not true of the US. The whole subject is confused and needs further study. To the Editors:
Professor M.F. Perutz, in his review of Marilynne Robinson’s Mother Country is dismayed that her account of the irresponsibility of British nuclear policy was based solely on several hundred stories in the British press, whose scientific accuracy she could not assess. He concludes by suggesting that “she should have stuck to writing novels.”
And yet he concedes the truth of her main charge, saying
There is much to be criticized about the plutonium factories at Sellafield and the misleading information they issued repeatedly about their radioactive discharges.
It is precisely this discovery, which she made while vacationing in the nearby beautiful English Lake district, that forced her to write her book. She learned that Great Britain had assigned to the Sellafield facility the role of the reprocessor of the worlds’ high-level commercial nuclear waste, a decision made by no other nation. Professor Perutz does not deny that today Japan and many other European nations happily dispose of their commercial nuclear waste by sending it to Sellafield for reprocessing. Disposal of the highly radioactive residue is accomplished by the simple expedient of dumping it into the Irish Sea.
Professor Perutz objects to her reliance on English press reports about high cancer rates now being found on both coasts of the Irish Sea as “monstrous exaggerations” since the results of 30 years of such disposal has only
increased the radioactivity of the Irish Sea by just under 1 percent, which can hardly be called a danger.
As a former member of the EPA Science Advisory Board, now engaged in examining official US data linking excess mortality to large scale nuclear releases, I can report that Ms. Robinson has good reason to fear for the health consequences of the radioactive pollution of the Irish Sea.
Professor Perutz fails to acknowledge that manmade low-level radioactivity, which has been introduced into the biosphere only since 1945, differs in one fundamental respect from natural or background radioactivity, which has been present for billions of years. It has been known at least since 1943 that nuclear fission products released into the biosphere have a far greater opportunity than natural radioactivity to enter into the food chain, with lethal results to those who then ingest them.
Richard Rhodes, on page 511 of “The Making of the Atomic Bomb” relates that in 1943, Fermi, worried that the fission bomb may not be developed in time, consulted with Oppenheimer on the following interesting project. He was generating large quantities of radioactive strontium in his nuclear pile, and wondered why it could not be dropped over the German land mass and thus kill as many millions as would be desired.
Oppenheimer and Teller agreed that strontium-90 “appears to have the most promise” for such a purpose because it would enter into the food chain and be concentrated in the bone marrow. Millions of deaths could result but with no assurance that military men would be affected quickly enough.
By 1958, both Pauling and Sakharov independently published their estimates of how many millions of lives would be prematurely cut short from the ingestion of fission products released into the biosphere from atmospheric bomb tests.
The Natural Resources Defense Council has recently estimated that, based on a detailed analysis of seismic records, US bomb tests in the period 1945–1962 released the equivalent of 585 megatons of explosive power. If one divides this terrifying figure by fifteen kilotons, the estimated power of the Hiroshima bomb, we can calculate that both super powers released into the biosphere the equivalent of 40,000 Hiroshima bombs in this 17 year period. This far exceeds the magnitude of any nuclear exchange deemed able to bring on a Nuclear Winter if concentrated within a few days. So massive an assault on the biosphere helps explain one of the great epidemiological mysteries of the 20th century. From about 1950 to 1965, mortality rates in the US and most advanced nations in Europe with adequate statistics, flattened out after many decades of steady annual improvement. It was only after the Partial Test Ban of 1963, that mortality rates began to decline again, but far more slowly than was true before 1950.
This bit of history suggests that Professor Perutz is right to
wonder why Robinson turned a blind eye to American nuclear plants that have polluted the countryside with radiochemicals.
By all means she should indeed deploy her literary eloquence to dramatize the American contributions to the nuclear madness of our times. In doing so she would be in the same company as such eminent scientists as Rachel Carson, Linus Pauling, Andrei Sakharov, Ernest Sternglass, John Gofman, Arthur Tamplin, Karl Z. Morgan, Thomas Mancuso and Alice Stewart. The latter five were all engaged at one time or another by the US government to study the relationship between cancer mortality and low-level radiation. The services of all five were terminated when they came up with the unwelcomed finding that the dose response of cancer mortality to radiation was “supralinear,” which means that there is not only no radiation level low enough to be “safe,” but that at the lower radiation levels the dose response rises most rapidly.
Professor Perutz should consider what this suggests for the Irish Sea, with only 1 percent so radioactive that its fish can not be eaten. That initial 1 percent may turn out to be capable of killing perhaps as many persons as the final 50 percent, if the pollution were to continue.
Jay M. Gould
Director, Radiation and Public Health
Project, United Church of Christ
Mr. J.M. Gould writes as though I condoned radioactive fallout wherever it comes from. On the contrary, I showed in my review that fallout from atmospheric nuclear tests has been severe, amounting to a collective dose of half a million man-sieverts released in 1963, the year of the atmospheric test ban, and fifty thousand man-sieverts still in 1986. By contrast, the total collective dose released by the accident at Windscale amounted to thirteen hundred man-sieverts, a minute fraction of the total due to the nuclear tests. Mr. Gould writes that Japan and other countries send their nuclear waste to Sellafield for reprocessing. This is incorrect. They send their spent nuclear fuel so that it can be reused. He writes that the radioactive residue is dumped into the Irish Sea. In fact the plant separates waste into high-, intermediate-, and low-level activity. Only the low-level waste was discharged into the sea, and this discharge is now being reduced to near zero. As to the entry of radionuclids into the food chain, my review gives figures for that entry and Mr. Gould will find more details in the literature quoted there. It is not correct that all nuclear fission products released into the biosphere have a greater chance of entering the food chain than natural radioelements. The plutonium released by Sellafield was concentrated in shellfish and seaweed, but the caesium 137 did not enter the food chain. Among the natural radioactive elements, radium, having chemical properties similar to those of calcium; and polonium, having chemical properties similar to those of sulfur and selenium, would also enter the food chain. Mr. Gould writes that the dose-response curve rises at low radiation levels. On the contrary, recent research suggests that spreading out of the dose over long periods reduces the average cancer risk by a factor of three (J. Liniecki, “Cancer risk estimates for high doses and dose rates and extrapolation to the low dose domain,” IBC Conference on Low Dose Effects, London 1989.) Mr. Gould misunderstands the meaning of an increase in radioactivity of the Irish Sea by 1 percent. This does not mean that 1 percent of the Irish Sea has become so radioactive that its fish cannot be eaten; rather it is as if the alcohol content of a glass of beer were raised from 6.0 to 6.06 percent. The additional 1 percent is more or less uniformly mixed in and makes little difference.
It is important to make a distinction between one’s attitudes to nuclear weapons and nuclear energy. Nuclear weapons pose a threat to mankind’s survival, while nuclear fuels could make man’s precarious reserves of fossil fuels last longer without contributing to the greenhouse effect. They are vital for countries like France and Japan which possess no indigenous fossil fuels. Mr. Gould quotes my opening sentence about the malpractices at Sellafield, but not my closing sentence, saying that none of these malpractices had the ecological consequences of global significance that Robinson attributes to them.
Sir Rudolf Peierls has pointed out an error in my review. I stated that the Hanford reactor used water as a coolant and as a moderator. In fact it uses graphite as a moderator. Furthermore I failed to spot a misprint in the proofs. Footnote eight states that one gram of radium undergoes 1010 atomic disintegrations per second. The correct number is 1010 (ten to the power of ten).
To the Editors:
If a nuclear power plant blew up in a forest but nobody was there to flee it, then would radioactivity really fall in the forest? Of course it would, but data on man-sieverts of radioactivity would disguise the incident. The data would show high radioactivity measured in terms of sieverts, but since no victim was present to receive the fallout there would be zero man-sieverts recorded. If we want to know how many people happened to be close enough to get hurt, then man-sieverts are a useful measure; but also we may simply want to know how intense the radioactivity level was, and on that issue measurements of man-sieverts tell us absolutely nothing.
In his apology for nuclear power M.F. Perutz compared the Three Mile Island, Windscale, and Chernobyl disasters in terms of man-sieverts. This tells us nothing about how intense the radioactivity levels were in the three incidents…yet Perutz allows or even encourages the reader to believe such information has in fact been conveyed. Since Perutz obfuscated on the meaning of his data, I don’t trust his sanguine conclusion or his macho sneer (“She should have stuck to writing novels”) at those who do worry about nuclear waste.
Alan Day Haight
Mr. Haight regards my use of man sieverts to convey the risk of exposure to radiation as misleading and would have preferred me to quote instead the total release of radioactivity from nuclear accidents. I am glad to provide this additional information. The table on the previous page lists the total radioactivity released, the total dose absorbed by the exposed populations, and also the dose absorbed by the most exposed persons, after the nuclear accidents at Windscale, Three Mile Island, and Chernobyl. Radioactivity and Nuclear Accidents
The total radioactivity released was three times greater after Three Mile Island than after Windscale and in that sense the accident at Three Mile Island was the more severe. On the other hand, the total dose received by the entire exposed population and the maximum dose received by the most exposed individual were greater after Windscale than after Three Mile Island. Therefore Windscale had a more severe effect on health and this is why I quoted man-sieverts rather than becquerels. Man-sieverts would not necessarily measure zero if no one lived near the nuclear accident. After Chernobyl, much of the collective dose was received in Byelorussia, several hundred kilometers from Chernobyl, because the radioactive cloud was carried there by the wind.
To the Editors:
M.F. Perutz, in his review of Mother Country made two mistakes in one paragraph. It was Arthur Young, not Adam Smith, who wrote “Every one but an idiot knows that the lower classes must be kept poor, or they will never be industrious” in his Eastern Tour of 1771. Also, England introduced universal schooling in 1870, not 1880.
J. Kevin Branigan
Rochester, New York
I took my quotation: “Everyone but an idiot knows that the lower classes must be kept poor or they will never be industrious” from J.A. Sharpe’s book Early Modern England, where it is attributed to Adam Smith. I am grateful for the correct attribution; 1880 instead of 1870 for the introduction of universal schooling was a copying error for which I apologize.