written December 7, 1972
During a talk on "Energy Policy" last week, the speaker (Dr. Griffiths) spoke in glowing terms about the future of nuclear energy in Canada and elsewhere.
The question period which followed made it very plain that many physicists at UBC regard opponents of nuclear power plants as hysterical alarmists who are talking through their hats. The mere mention of Dr. John Gofman's name elicited howls of derision from a number of people in the room.
I would like to propose a public debate on the question of nuclear power plants, under the auspices of the B.C. Environmental Council, if Dr. Griffiths or any other members of the Physics Department would care to participate in such an event.
In the meantime, I have prepared some notes designed to clarify some of the issues involved, which I hope will be of interest to faculty members and graduate students of the department.
Gordon Edwards, Ph.D.
Department of Mathematics
University of British Columbia
An Open Letter to Physicists
Table of Contents
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Biological Ignorance
The history of atomic energy is one of repeated over-optimism, especially with regard to biological effects. Part of the reason for this, no doubt, is that physicists don't generally know very much biology. Nuclear physicists, for example, rarely spend a significant portion of their careers in the study of the biological effects of radiation.One of the factors that is often ignored in talking about the release of low-level radioactive wastes into the environment is the fact that biological organisms can concentrate those wastes to a dangerous level. During the atmospheric testing of the 1950's, the Atomic Energy Commission predicted (correctly) that much less fallout would reach the ground in arctic regions than in temperate regions of the United States. They concluded (incorrectly) that Eskimos would not be in danger of accumulating dangerous amounts of fallout. They didn't know that food chains can behave in peculiar ways.
Lichens (a groups of composite organisms, each of which consists of an alga and a fungus living together) have no functional roots, and often grow on rocks rather than soil. They absorb their mineral nutrition in the form of dust taken directly from the air. As a result they absorb radioactive fallout directly, without the dilution and discrimination processes which operate when fallout is absorbed through roots. Caribou eat great quantities of lichen (many times their own body weight) and therefore take up excessive amounts of radiation from fallout. At the end of the food chain, caribou meat makes up a substantial portion of the Eskimo's diet, producing the unexpectedly large amounts of fallout radiation in their bodies. [1]
Another well-documented case of "biological magnification" occurred in Utah. During a series of tests in Nevada, fallout clouds passing over Utah (which the Atomic Energy Commission had said couldn't happen) deposited a scattering of iodine-131 on the grass. Being widely spread, this caused no alarming readings on outdoor radiation meters. But dairy cows grazed these fields, passing the radioactive iodine on to local children through their milk. Like ordinary iodine, it concentrated in the thyroid glands of these children, leading to abnormal growths in the thyroids of nine of these children almost 15 years later. The Atomic Energy Commission, which had completely ignored the danger of radioactive iodine as a hazard to man, finally admitted that in fact iodine-131 was responsible for the heaviest doses of radiation to man in the entire atmospheric testing program. [2]
Biological magnification is based on the principle that predators always consume many times their own body weight of their prey. If the prey happens to contain some substance that is stored in the body without being excreted (such as DDT), it follows that the predator will end up with a much higher concentration of this substance than can be found in the prey. Thus the substance appears in ever-increasing concentrations as you go up the food chain, and the full extent of this process may not become apparent for many years.
It is important to note that once such a substance is widely disseminated in the environment, even at low concentrations, it will continue to accumulate and concentrate as it goes up the food chain long after the substance has been discontinued in use.
One of the organisms that concentrates radioactivity is seaweed -- and in Wales and the Canadian Maritimes, people eat food made of seaweed. Oysters and shellfish also concentrate radiation. Algae concentrate radioactive phosphorus from the water 200,000 times; this substance also concentrates in the bones and scales of fish. In a river in which the concentration of phosphorus-32 is well below the level demanded for drinking water, fish may eventually become too radioactive for human consumption.
In Par Pond, where the Oak Ridge Laboratory dumped some of its low-level wastes, it was found that even when the concentration of cesium-137 was only 3 hundredths of a millionth of a millionth of a curie, the flesh of the bass caught in the pond contained 100 times this amount. Similarly, strontium-90 in the bones of bluegill was 1,000 times the level in the water, and radioactive zinc was 8,720 times the level in the water.
Caddis fly larvae in the Columbia River (where the Hanford nuclear plant discharges) achieved concentrations 150,000 times that in the water. Birds also concentrate radioactivity, and being higher up in the food chain, they end up with correspondingly higher concentrations. Thus swallows may carry 75,000 times the ambient level, because they feed on insects which in turn have concentrated it from algae which in turn have concentrated it 2,000 times above the level in the water. [3]
Since many of the radionuclides released from nuclear plants have long half-lives, their presence in the environment will be essentially cumulative. It is therefore most important to ask what the long-term consequence of small doses of radiation may be.
Some Biological Effects
Time-lag factors are something which physicists are just not used to taking into account, and -- quite frankly -- they have very little experience to draw on in their particular field of study. It may take twenty years or more before the biological effects of exposure to radiation become known. Studies of the survivors of Hiroshima and Nagasaki showed that all kinds of cancer had a very much higher incidence among those who had been exposed to radiation, but that these cancers did not develop until 5, 10, 15, or 20 years after the event.
There is a "latency period" during which no increase in the incidence of cancer is observed -- and then comes a whopping big increase. For leukemia, the latency period is about 5 years, whereas for other types of cancer it can be much longer -- for thyroid cancer (as hinted above) the latency period is about 13-15 years. Studies of uranium miners as well as silver and cobalt miners (all of whom were exposed to radon gas in the mines) confirm these latency periods. [4]
Before stating Gofman's conclusions with regard to low-level radiation, it might be worthwhile to briefly state who he is, since he seems to be held in considerable scorn by some of the physicists around. He is a full professor in the Department of Medical Physics at Berkeley. Besides being an M.D., he also has a Ph.D. in nuclear physics from Berkeley. He is a co-discoverer of U-232, Pa-232, U-233, Pa-233, and of slow and fast neutron fissionability of U-233. He is also co-inventor of the uranyl acetate and columbium oxide separation processes for plutonium. He has taught in the radioisotope and radiobiology field for over 20 years, and has done research in radiochemistry, macromolecules, lipoproteins, coronary heart disease, arteriosclerosis, trace element determination, and x-ray spectroscopy -- as well as radiation hazards.
In 1963, responding to growing criticism and recognizing that it had made many serious errors in the past, the Atomic Energy Commission asked Dr. Gofman to become an Associate Director of the Lawrence Radiation Laboratory and conduct a thorough long-term investigation into the biological effects of radiation. This investigation took more than six years, and it included careful correlation of studies which had already been done on miners, survivors of Hiroshima-Nagasaki, people exposed to diagnostic medical and dental x-rays, radiation technicians, and even large populations living in different locations where the background radiation levels showed significant differences.
Incidentally, just recently (October 1972) Dr. Gofman was awarded the Stouffer Prize "for pioneering work on the isolation, characterization, and measurement of plasma lipoproteins, and on their relationship to arteriosclerosis. His methods and concepts have profoundly stimulated and influenced further research on the cause, treatment, and prevention of arteriosclerosis." (Quotation from the citation accompanying the award.) The Stouffer prize, which carries a $50,000 cash award, is one of the highest existing honours in the field of heart research.
The purpose of reciting these credentials is not to make Dr. Gofman seem an infallible godlike expert, but to indicate how absurd it is for any physicist to make light of his work without ever having studied it or the data on which it is based in any great detail. After all, physicists are not biologists -- and it would be surprising indeed if a physical knowledge of nuclear processes should make one an expert on the biological effects of such processes. How much weight, I wonder, would physicists give to a community of biologists who scornfully rejected the theory of relativity as ludicrous and patently absurd, because it didn't fit with their biological intuitions?
What exactly was Gofman's "controversial" conclusion? Simply this: that the biological effects of radiation (in terms of increased occurrences of cancer, leukemia, and genetic damage) are linearly related to the accumulated dose of radiation received, regardless of whether it's a big dose administered all at once or a small dose administered over a long period of time. (Even before his work, the International Commission on Radiological Protection and the U.S. Federal Radiation Council had stated clearly that it is unsound to count on any protection against cancer and leukemia from slow delivery of radiation.)
This observation agrees with the theoretical supposition, that if a cell is alive and able to reproduce after exposure to radiation, but with damaged DNA or RNA instructions, its descendants may become manifested as cancerous growths many years after the original exposure. The probability of a cell being damaged in such a way is presumably proportional to the dose of radiation, regardless of how it is delivered. Thus uranium miners have consistently displayed almost three times the incidence of lung cancer than the rest of the population, although the onset of cancer may be delayed from 10 to 20 years after initial exposure -- often, indeed, after the men have retired or taken up some other form of employment. [5]
If Gofman is right, then there is no such thing as a "safe" threshold level below which no damage is done. To argue that there's a "background level" of radiation anyway, so it's all right to expose people to radiation as long as it doesn't exceed the background level, is sheer sophistry of the worst kind. It amounts to saying that it is "acceptable" to have twice as many people die from cancer, leukemia, and genetically-related diseases than would have died from natural irradiation. Gofman figured that if the U.S. population were exposed to this dose (the dose the Atomic Energy Control Board considers "acceptable" here in Canada is three times larger!) there would be at least 32,000 additional deaths every year from cancers and leukemias, over and above the spontaneous rate of incidence of these illnesses, and a much higher number of deaths from genetic causes. [6]
The extent of genetic damage as a result of radiation exposure, though known to be great, is still a mystery. Since the defective genes will be passed on through successive generations, the full effects will not be known for a long time -- another "time-lag" effect, but on an even larger scale. Even such non-cumulative radionuclides as carbon-14 and tritium are potentially very dangerous in this respect. Being chemically identical to ordinary carbon and hydrogen , these isotopes can be built right into any type of living tissue, including DNA molecules, where they can wreak genetic havoc. Tritium may prove to be a major biological hazard. The advent of thermonuclear plants would make the tritium problem very severe indeed.
One of the problems with tritium is that it is very hard to control -- it leaks out of aluminum and stainless steel fuel canisters, and it passes most valves and seals. Incidentally, the Canadian reactor produces not only more high-level waste than its U.S. counterpart, but also very much more tritium. It is well known, of course, that the traditional radioactive pollutants are genetically very dangerous too. Strontium-90 (a chemical relative of calcium) accumulates in bone tissue, for example; but when it disintegrates it produces yttrium-90, which tends to lodge in the gonads, where it can cause damage to eggs or spermatozoa. [7]
Nuclear Power Plants
It is true that, under "normal" operating conditions, the amount of radioactive material released from a reactor through exhaust stacks or effluent water is very small in comparison with background levels. Nevertheless, the chemical properties of these substances may result in biological magnification, producing doses very much larger than anticipated. Moreover, these substances may tend to concentrate in one part of the body (e.g. iodine-131 in the thyroid, strontium-90 in bone, cesium-137 in muscle tissue) creating specialized hazards.
Professor Pendleton has shown that cattle thyroids in Utah were still displaying radioactive iodine in 1962; in view of the ban on atmospheric testing and the short half-life of iodine-131 (8 days), this could only come from reactors and reprocessing plants. In 1968 the U.S. Public Health Service confirmed the presence of radioactive iodine in cattle thyroids in Georgia, Iowa, Kansas, Louisiana, both Carolinas, Oklahoma, S. Dakota, Tennessee, and Texas.
The longer half-lives of other radionuclides (e.g. 28 years for strontium-90 , 33 years for cesium-137 , and 6000 years for carbon-14) makes it impossible to say for certain whether increased levels of these radionuclides are due to recent additions to the environment or have simply worked their way up through the food chain. For a long-lived substance, a thousand emissions of one curie each amounts to much the same thing as one emission of 1000 curies. Also, in times of abnormal functioning, sizable amounts of radioactivity may be released from nuclear power plants, and there are plenty of documented instances of this. [8]
But the really crucial consideration is the possibility of a major accident at a nuclear plant. A single 200 megawatt reactor, after one year of operation, contains more radioactive cesium, strontium, and iodine than the amounts produced in all the nuclear weapons tests ever conducted. These high-level wastes have to be perfectly separated from the environment, not just for 600 years, but for over 1,000,000 years -- far longer than any political entity has existed in the whole of human history.
Long term management of high-level radioactive waste is an extremely difficult problem, and any attempts to minimize it are in vain.
And what about accidents? In its famous Brookhaven Report of 1957, the Atomic Energy Commission indicated what the results of a single major accident at a relatively small reactor 40 miles from a city might be:
- 3,000 to 4,000 deaths immediately from radiation poisoning,
- 50,000 deaths later on from radiation-induced injuries;
- up to 150,000 square miles of land contaminated,
not to mention
- contamination of water supplies and
- evacuation of half a million people.
Anyway, how do you compute the probability of an accident? Do you count on the possibility of sabotage? (It would make an even bigger splash than kidnapping Pierre Laporte). Or the possibility of war? (What would happen if an old-fashioned conventional bomb were dropped on such a reactor?) What about the possibility of an airplane crashing into a reactor? (Remember, Pickering is also going to be the site of a huge airport. Only last month we witnessed the spectacle of a band of hijackers threatening to crash the plane they had hijacked into a nuclear installation. It could happen accidentally too.)
All of this doesn't begin to consider the very real possibility of a large industrial accident occurring within the plant as a result of mechanical and/or human failure. Accidents have occurred at Chalk River (resulting in the release of 10,000 curies of fission products), the Enrico Fermi plant outside Detroit (leading to a partial meltdown of the core and fears of explosion), the Windscale plant in Great Britain (which spewed vast quantities of radioactive debris into the environment), and others. In 1970 there was a close call at the huge Hanford reactor and a failure at the Oak Ridge Research Reactor, the later involving an "almost unbelievable" combination of 3 separate human errors, 2 installation errors, and 3 design errors. [9]
There are many other reasons why nuclear reactors are considered unsafe. One is the very serious problem of waste disposal. Another is the problem of transporting high-level wastes to a proper disposal site : how do you guarantee against an accident en route? Another problem is concerned with a black market in plutonium, which is the essential ingredient for making cheap atom bombs. According to expert testimony, it is by no means inconceivable for a terrorist group of moderate means to manufacture a home-made atom bomb. (Instead of holding an airplane hostage, they could hold a city hostage!)
Another problem, often overlooked, is the mountains of radioactive uranium tailings which have been shown to be potentially dangerous sources of radioactive contamination. In the U.S. there are now 30 million tons of this sand-like stuff, generally lying in uncovered heaps, being washed into water systems by wind and rain. The water in the San Miguel River in Colorado was found to contain 30 times the "acceptable" level of radiation, while algae and alfalfa were much more heavily loaded, as a result of uranium tailings being washed into the river. There is also the matter of thermal pollution, which is again a complex biological question, not to be dismissed lightly. [10]
A Rational Energy Policy
Energy consumption has been doubling in Canada every ten years or so. In large part, this is the result of intensive advertising to "Live Better Electrically", combined with preferential rates for large users of electricity. This growth in electricity consumption is related more to the production of garbage than to the quality of life -- for example, aluminum (requiring huge amounts of electricity for smelting) is increasingly being used for disposable beer cans and TV Dinner Trays.
The first priority in any energy policy should be to reverse these trends by urging people to use less (not more) electricity, as is being done by Consolidated Edison of New York, and by eliminating preferential rates for electricity gluttons. [11] There should also be a radical new policy of honesty with the public, to find out whether they are actually willing to take the risks in order to get more electrical energy. At present, they are lulled into thinking that there are no risks associated with nuclear energy.
In the Atomic Energy of Canada Ltd. report to the Nanaimo Chamber of Commerce , entitled "Nuclear Power for Vancouver Island", it was stated that "At very low doses, radiation is harmless -- that is, physiologically tolerable." That is a lie, and the Atomic Energy of Canada Ltd. knows it -- or should know it.
To someone who dies of leukemia, it doesn't much matter whether it was caused by a large or small dose of radiation. It's a bit like the photoelectric effect: the magnitude of the effect is independent of the intensity of the dose, only the frequency of the effect is dependent on dosage. Moreover, there is reliable evidence indicating that infants and children are far more susceptible to damage from radiation than an adult, and foetuses are more sensitive still, presumably because of the much more rapid division and growth of their cells. In the vicinity of a nuclear plant, there is no way of preventing these young people from accumulating radiation internally.
It has been shown that a single diagnostic x-ray to the abdomen of a pregnant woman can increase the chance of the unborn child developing childhood cancer or leukemia by 50 percent.
X-rays can be avoided; food cannot. Thus the question of nuclear power is an ethical question of great scope, and the people who are going to take the risks should be asked whether they are willing to have a small number of human sacrifices to pay for more electricity. [12]
Small? Well, assuming, of course, that there are no major accidents.
Footnotes
- See chapter 2 of Science and Survival by Barry Commoner for an account of the arctic fallout question and the iodine-131 scandal in Utah.
- In 1960, Dr. Knapp (a member of the Atomic Energy Commission's Fallout Studies Branch) was asked to write a report on "The Contribution of Hot Spots and Short-Lived Activities to Radiation Exposure in the US from Nuclear Test Fallout". Just before this paper was published, he made what he called a "startling discovery". He found that the Atomic Energy Commission had totally overlooked the effects of iodine-131 during the period 1951-1953 through a total lack of any monitoring for this substance. He also found that the dosage of iodine-131 had been underestimated by as much as 1000 percent in certain parts of the USA. For instance, he reckoned that infants in the town of St. George Utah, had received doses of from 120 to 440 rads to their thyroids, as a result of the heavy fallout from the 32 kiloton shot HARRY, which was exploded 120 miles from the town on May 19, 1953.
In 1963, Drs. Pendleton and Mays testified that approximately a quarter of a million children in the state of Utah may have been exposed to average thyroid doses of 4.4 rads prior to age 2, and that in 1953, several hundred infants in St. George (Utah) received doses to the thyroid ranging from 136 to 500 times the maximum permissible dose. See Fallout, Radiation Standards, and Countermeasures, JCAE Hearings, Part I (June 1963) and Part II (August, 1963).
In late 1962, the Atomic Energy Commission admitted that radiation dosage from iodine-131 may have reached 1.5 rads/year in some parts of the country (New York Times, October 18, 1963). While still far below the estimates of Knapp, Pendleton and Mays, these doses are the largest that the Atomic Energy Commission has ever admitted to in connection with fallout in the U.S.A.
- Most of these figures can be found in Sheldon Novick's book, The Careless Atom. However, any book on radioecology will provide similar information -- see for example Radioecology of Aquatic Organisms by Polykarpov (translated from Russian).
- Information about latency periods can be found in any recent book on the biological effects of radiation. For some time, it was erroneously believed that leukemia was the only cancer that resulted from low-dose exposure; it is now well-established that almost all other kinds of cancer can also result. The reason these other cancers were missed before is that they have a much longer latency period. Today it appears that the risk from low-dose radiation is at least 20 times greater than was thought 20 years ago, when the radiation standards were set.
- For a complete account of the callous disregard for minimal safety standards in US uranium mines until very recently, see Peter Metzger's excellent book, The Atomic Establishment.
- 'Population Control' through Nuclear Pollution, by Arthur Tamplin and John Gofman.
- Joshua Lederberg, Nobel Prize winner in Genetics, estimates that if the entire U.S. population were exposed to the maximum permissible dose of radiation, then the extra public health burden due to genetically related diseases induced by radiation would eventually cost 10 billion dollars a year. (Washington Post, July 19, 1970). His estimate is based on a 10 percent increase in mutation rate at this dose level. Gofman and Tamplin have estimated that mutations may increase by as little as 5 percent or by as much as 50 percent at this dose level. The dangers of carbon-14 have been pointed out by Linus Pauling (winner of two Nobel prizes) among others. Useful information about tritium can be found in a 1968 Atomic Energy Commission publication by D. G. Jacobs, entitled "Sources of Tritium and its Behaviour upon Release to the Environment"
- Chapter 8 of The Doomsday Book by Gordon Ratty Taylor contains much valuable information of this kind.
- The 3 major accidents that are mentioned here and the Brookhaven Report are all well described in The Careless Atom by Sheldon Novick.
- Waste disposal is discussed in many books. The most recent scandal, the "Salt Vault" episode, is described in The Atomic Establishment by Peter Metzger. Articles have appeared in the Wall Street Journal (June 18, 1968), Science magazine (April 1971), and many other places regarding the plutonium problem. For information on uranium tailings, see The Atomic Establishment by Peter Metzger or The Great American Bomb Machine by Roger Rapoport.
- An excellent article in Science (December 8 1972) argues that we could cut our energy consumption by 1/4 without any significant changes in life-style. Consolidated Edison of New York has already begun to advertise for less rather than more electrical consumption. It has been proposed by many people that large users of electricity should be charged more per kilowatt-hour rather than less. There are also many articles dealing with alternative energy sources in the l972 issues of Science magazine and other places.
- The study of the effects of radiation on foetuses was done by Dr. Alice Stewart in England. It is acknowledged to be one of the most careful studies ever done in the field of radiobiology. Her results were subsequently confirmed by Dr. Brian MacMahon of the U.S. (Harvard University) using American data.
[ Uranium: Known Facts and Hidden Dangers (Salzburg address) ]
[ Reactor Accidents at Chalk River -- The Human Fallout ]
[ The Health Hazards of Tritium -- Excerpts from Source Documents ]
