CANDU and SLOWPOKE

While the United States - with its post-World War II enrichment technology and capacity - built power reactors using enriched uranium, the Canadians took a different approach. You may recall that deuterium (2H) reacts with oxygen to form "heavy water" - an unusually good moderator that bounces back and slows down neutrons that might ordinarily escape the reactor. The most interesting thing about the Canadian CANDU heavy water reactor - from the standpoint of community or home power plants - is that it uses natural (unenriched) uranium. This doesn't get them off the hook from an initial energy expenditure, however, since heavy water is expensive to separate - about $100 per pound and costing $100 million dollars for a full-scale 1,000 megawatt reactor. It does, however, eliminate the problem of enrichment. The CANDU design has many parallel fuel assemblies with the heavy water coolant/moderator flowing through each. To refuel the reactor, it doesn't need to be shut down; you just cut off the water to stop the nuclear reaction in a section isolated for refueling, and then change out the "spent" fuel assemblies.

["Spent" fuel assemblies aren't really spent at all - they have more than 95% of the initial fuel remaining with only a few percent of "daughters" that contaminate the rest and absorb the needed neutrons.]

Even more interesting from the standpoint of decentralization is the Canadian SLOWPOKE reactor, which is as safe and secure as a Sierra Club official working for the Environmental Protection Agency. [Safe LOW POwer Kritical Experiment - but it's not experimental anymore, having been in operation for more than twenty-five years. (Canadians may be great reactor designers, but they seem to have a little problem with their spelling.)]

Figure 34 shows a cutaway sketch of this "pool" type reactor - so named because it operates submerged in a pool of water. Unlike PWRs and BWRs, it does not have "defense in depth" - because it doesn't need it. The laws of physics provide it with more than enough protection.

The original design has a maximum operating temperature of 80 degrees Celsius with a cylindrical core about nine inches in diameter by nine inches in height. Surrounding the enriched-uranium fuel assembly are beryllium reflectors, which keep the reactor critical... as long as the water density remains high. If the reactor "heats up," the lower water density slows the reaction bringing the temperature back to the design point. [SLOWPOKE I and II have been operational for some time; the series is now up to V or VI, but I haven't been able to get much information on the later models.]

Suppose all the water evaporates or is sloshed out by an earthquake? Naturally, the reaction stops, as the moderator is gone. But also the power density is so low that nothing happens to the fuel. The reactor just goes dormant until someone takes an action to bring it back to life. [Typically the operators do not have access to the reactor.]

As Canadian scientist Dr. John Hilborn, who conducted experiments leading to the SLOWPOKE, said, "It is safer without operators than with them." [From an interview with Petr Beckmann, Access to Energy, Vol. 8, No. 9, May 1981, pp. 1-2.]

The original SLOWPOKEs were not designed as power reactors. Their heat output (which is considerably higher than any possible electrical output) is a mere twenty kilowatts, equivalent to about thirteen hair dryers. Their function, as mentioned, was not to produce electricity but to transmute certain materials into radionuclides, primarily for medical purposes. But the concept of a low-temperature, inherently safe, non-polluting, inexpensive-to-fuel, produce-power-where-you-need-it reactor is intriguing for those who would like to have energy independence. [Some electric utilities might oppose such a competitive concept, but they would, as mentioned, be in the best position to provide service for local power reactors.]

Power Reactors

In the United States, power reactors are entirely of the PWR (pressurized water reactor) or the BWR (boiling water reactor) types. In both cases, water is used as the coolant and the moderator, which provides a very interesting advantage that probably no one has bothered to mention to you: If the coolant is lost, the chain reaction stops. Depending on the length of time the fuel has been producing power, the fuel rods may or may not be thermally and radioactively "hot" from the daughters of the fissioning process. Even in the worst case, the heat generated is no more than 1% or 2% of that during normal operation. This is why the "disaster" at Three Mile Island didn't really happen - except in the minds of the uninformed.

While the Japanese installed the first Advanced Boiling Water Reactor (ABWR) in 1996, none of the new, modular designs have seen the light of day in this country. Not only have we been blinded by the non-threat of low-level radiation, but the cost of building a nuclear plant has escalated by a factor of seventeen, after considering inflation - mostly from construction delays caused by environmentalist lawsuits. (The above-mentioned Japanese ABSR plant took fifty-two months to build - compared with more than eleven years for the most recent plant in the United States.) I would say the new designs are even safer than the old - but how do you get safer than no deaths, no injuries, and no negative effects to the public from several thousand reactor years of operation with thousands of gigawatt-hours of life-enhancing electrical energy having been generated? [Some of the media scream "disaster" when ten gallons of water with 1/80 the radioactivity of salad oil leak out in the process of heating and otherwise providing life-giving energy to an entire city. Why doesn't it make front-page news when some one falls off the roof to his death trying to clean the solar collector - which provides a few puny kilowatts of solar energy for warming the hot water... when the sun is shining?]

Nonetheless, neither the PWR or BWR has much promise for miniaturization and "local" use as - by nature - they operate with high-power densities, which have the potential to cause a messy and expensive loss-of-coolant accident. They also require pumps, back-up pumps, and relatively elaborate controls.

All of these U.S. power reactors use enriched uranium as a fuel, as do reactors in France (where 80% of the electrical power comes from nuclear energy), Japan, England, and most other countries. The enrichment process starts with natural uranium, which is dissolved in acid to produce uranium hexafluoride gas. This ultra-corrosive gas is then pumped thousands of times through membranes where the lighter U235 passes through just a little bit easier than the U238. For power reactors, the U235 is enriched from 0.7% to about 3.5%, which takes not only lots of time but considerable energy. ["Bomb grade" U235 must be enriched to 90% - an extremely difficult process. Thank goodness, or any crackpot might be able to do it.)]

Mankind and Energy

The history of mankind is, in large part, a history of the harnessing of energy sources. Prehistoric man had only his own muscle power to wrest a livable habitat from his rugged environment. The discovery and control of fire eventually yielded metals, which improved the efficiency of muscle power and allowed the practical cultivation of crops. Domestication of animals - the horse, ox, donkey, elephant, dog - multiplied the energies of a man by severalfold. And this is where mankind remained for several thousand years.

While water wheels were used by several cultures for irrigation, the harnessing of hydropower was the product of the Industrial Revolution in mid-eighteenth-century England. The windmill was another attempt by man to increase his energy - one which is still going on, and still has the problem (as does hydropower) of requiring the cooperation of nature to utilize energy from the sun. (Both hydro and wind power are actually forms of solar energy, as are fossil fuels; but wood, coal, oil and natural gas don't require quite as much cooperation from nature.)

Man's (and beast's) burden was lessened immeasurably by English engineer Thomas Savery who, in 1698, invented the "fire engine" to pump water from mines. Thomas Newcomen in 1705 and James Watt in 1763 improved the design to where the steam engine could be used for a variety of purposes, including transportation.

As the Industrial Revolution moved east to the continent, so did the desire for ways to deliver more energy - with less human and animal effort. Frenchman Jean Joseph Etienne Lenoir is credited with building the first gasoline internal combustion engine in 1860, while German Rudolf Diesel patented his engine in 1892 (and mysteriously disappeared from a London-bound German ship just prior to World War I). The late nineteenth century saw the discovery and application of electrical principles by Dane Oersted, Frenchman Ampere, German Ohm, Englishman Faraday, American Henry, and Scotsman Maxwell - thus allowing energy to be transmitted from point of generation to point of need.

If we track both population and energy availability, we see that there has been a sixtyfold increase in industrialized countries since Savery (compared with a world population that had been constant for a thousand years) and the same order of magnitude of energy usage per capita. [Aren't you glad? - or there would be only a 1.6% chance that you would be here.] But today, we have reached a plateau.

Under the Grandstand

The first man-made chain reaction occurred under the grandstand of the University of Chicago football field on December 2, 1942, in what was known as an atomic "pile." It was so named because it was constructed of a "pile" of 45,000 high-purity graphite bricks (250 tons), with 19,000 drilled holes to contain the approximately 93,000 pounds of uranium metal and uranium oxide along with the cadmium control rods. When operating at its design point, it generated a half watt of power - enough to almost power a pencil sharpener. (Fortunately, it was not designed as a power reactor, but as an experiment to prove the "chain reaction" hypothesis.)

Why the "high-purity graphite bricks?" It has to do with the statement a few paragraphs back about "... if the energy of the neutron is within a certain range." When we want to make little rocks out of big rocks, we are accustomed to using a bigger hammer and swinging hard. Not so in the nuclear world. In order for a neutron to have a decent chance at fissioning a U235 nucleus, it must be slowed down by the action of a moderator. Carbon - as long as it is of high enough purity to avoid absorbing the neutrons - is a good moderator, although, as Chernobyl demonstrated, it has a few potential problems - which is why U.S. power reactors never use this material... or this type of "graphite reactor." It is typically used in military reactors for the production of plutonium - which reportedly was one of Chernobyl's functions, in addition to generating power. [Other uses would be in research reactors, as well as in reactors for use in creating medical radionuclides.]

Footnote to chapter: There is much evidence that a natural reactor "happened" in Western Africa in the Republic of Gabon at Oklo some 1.7 billion years ago when the ratio of U235 to U238 was considerably higher. It appears to have operated in accordance with the Nuclear Regulatory Commission rules of that time and was safely shut down after several hundred thousand years of operation. See Oklo Reactor, Scientific American, August 1976.

Enter the Atom

Let's return for a short graduate course from Hormesis U. about "splitting the atom."

We've already seen that U238 is an isotope of uranium with a half-life of 4.5 billion years. [I realize I said I was going to refer to isotopes in the form of 238U or uranium 238. But U235 and U238 are such commonly used abbreviations to denote these isotopes that I will be using them in this chapter.]

With a lump of this element and the proper instruments, you would find there is another isotope, U235, which amounts to only 0.7% of the total mass. Yet it is this tiny fraction that makes uranium the tremendous source of safe and reliable energy - not to mention the fearful master - that it has become.

U235, like its more plentiful sibling, is an alpha emitter - but has a considerably shorter half-life... a mere 3,800,000 years, meaning that it was considerably more plentiful a billion or so years ago. [U235 is sometimes referred to as "actinium" or "uranoactinium."] It, along with plutonium 239 and U233, are the only isotopes that are fissionable - a phenomenon described below.

Under normal conditions, we can expect to see a U235 atom occasionally decay into an isotope of thorium and a helium nucleus (an alpha particle) similar to all radioactive isotopes experiencing alpha decay. ["Occasionally" takes on a new meaning in the atomic world. Our roughly penny-sized gram of U235 would experience approximately 80,000 nuclear disintegrations per second.]

But let us suppose that a stray neutron smacks into the nucleus of an unsuspecting U235 atom. If the energy of the neutron is within a certain range, our U235 target atom fissions, that is, breaks into pieces. [This was first observed by an unbelieving Lise Meitner in December 1938. She had observed barium, with an atomic number of 56, arising when she bombarded "actinium" with neutrons.]

It usually splits into two roughly equal parts, and most important, ejects about two neutrons. Obviously no atom could eject or emit about two neutrons, but, on average, that is what a fissioning U235 atom sends out of its nucleus.

Imagine, then, one of these neutrons hitting another U235 atom, which emits two neutrons with at least one of these splitting another atom... and so on, and so on. As you have no doubt already figured out, this is what is known as a chain reaction. When the ratio of fissioned atoms in successive generations is equal to one - that is, when one splitting atom causes exactly one more to split - the reaction is said to go critical. What happens to the other neutrons? They either escape from the volume of uranium, or they are absorbed - either unintentionally by structural material, or purposely by control rods made of boron, aluminum, cadmium, or several other neutron-absorbing materials - in order to keep the reaction under control (that is, to keep it from going super-critical). Does a super-critical reaction cause a bomb-like explosion? Not at all; if it did, bomb development by the Manhattan project would have been relatively simple rather than requiring the best theoretical physics minds on two continents. But super-criticality is no picnic. It causes rapid rises in fission reactions, leading to very high temperatures that cause structural damage, torrents of neutrons, and "steam explosions." Bad, yes, but still light years away from the mushroom-shaped cloud.

Let's look at a few different types of reactors, with an eye for those that might allow decentralization of electric power generation.

Mankind and Energy

The history of mankind is, in large part, a history of the harnessing of energy sources. Prehistoric man had only his own muscle power to wrest a livable habitat from his rugged environment. The discovery and control of fire eventually yielded metals, which improved the efficiency of muscle power and allowed the practical cultivation of crops. Domestication of animals - the horse, ox, donkey, elephant, dog - multiplied the energies of a man by severalfold. And this is where mankind remained for several thousand years.

While water wheels were used by several cultures for irrigation, the harnessing of hydropower was the product of the Industrial Revolution in mid-eighteenth-century England. The windmill was another attempt by man to increase his energy - one which is still going on, and still has the problem (as does hydropower) of requiring the cooperation of nature to utilize energy from the sun. (Both hydro and wind power are actually forms of solar energy, as are fossil fuels; but wood, coal, oil and natural gas don't require quite as much cooperation from nature.)

Man's (and beast's) burden was lessened immeasurably by English engineer Thomas Savery who, in 1698, invented the "fire engine" to pump water from mines. Thomas Newcomen in 1705 and James Watt in 1763 improved the design to where the steam engine could be used for a variety of purposes, including transportation.

As the Industrial Revolution moved east to the continent, so did the desire for ways to deliver more energy - with less human and animal effort. Frenchman Jean Joseph Etienne Lenoir is credited with building the first gasoline internal combustion engine in 1860, while German Rudolf Diesel patented his engine in 1892 (and mysteriously disappeared from a London-bound German ship just prior to World War I). The late nineteenth century saw the discovery and application of electrical principles by Dane Oersted, Frenchman Ampere, German Ohm, Englishman Faraday, American Henry, and Scotsman Maxwell - thus allowing energy to be transmitted from point of generation to point of need.

If we track both population and energy availability, we see that there has been a sixtyfold increase in industrialized countries since Savery (compared with a world population that had been constant for a thousand years) and the same order of magnitude of energy usage per capita. But today, we have reached a plateau.

What's Cookin' in Those Reactors

The use of thorium in CANDU type reactors would give earthlings sufficient energy to provide for the next seven ice ages. - Edward Teller [From "CANDU Is Really Remarkable," Power Projections, May, 1980.]

Evidence in the preceding chapters strongly indicates that hormetic stimulation from low levels of radiation has great potential for improving human health and vitality. For this to come about, we must be freed from the fears promoted by the Linear No-Threshold (LNT) theory and the principles of "collective dose."

Freedom from these unreasoned fears would also promote the growth of other nuclear technology, the most important of these probably being power generation. Availability of energy can be seen to coincide with both standard of living and health. The environmental primitivists would have us live in a pristine wilderness - precisely where we see the absolute worst of the human condition. (And no McDonald's.)

Many of us would be interested in achieving greater independence from the utility companies (often government monopolies) and the government itself. We see all manner of solar toys and wind generators in Mother Earth News, which promise energy independence. Sure, as long as you have a staff of electrical and mechanical engineers, plus thousands of acres to mount the collectors or turbines, and a maintenance crew of dozens to keep things running. But as we shall see, nuclear energy has the promise to free those of us who would opt out of the government/utility networks. And while I take aim at some utilities that have become slovenly where licensure requirements have virtually eliminated competition, these same utilities would be in the best position to be the providers of community or residential power sources, having both generation and customer knowledge.

Before You Spend $4,000 to Shorten Your Life

The observed lung cancer rates of females in high residential radon areas in the former uranium mining areas in Southern Saxony are substantially lower than the population average of East Germany. - Professor Klaus Becker, German Standards Institute

Bernard Cohen, doctor of science and professor emeritus at Pittsburgh University, is a liberal Democrat. [He mentions this in his terrific book, The Nuclear Energy Option, Plenum Press, New York, 1990, p. 269.] I probably would disagree with everything he believes in politically. But Dr. Cohen is also a scientist. He is convinced that the way mankind can continue to raise itself up from our back-breaking labor and mud huts is through increasing our knowledge about the world we live in. And most important, he is convinced this knowledge is objective. We can find truth. It is verifiable. It can stand on its own.

In by far the largest "ecological" study of low-level radiation ever made, Professor Cohen was attempting to refine the Linear No-Threshold theory. But, in his words, "It came as a great shock to me that my data ran contrary to the LNT, and I didn't fully believe it until about 1993 - when I shut off the $1,200 radon reduction system in my home to save electricity." But he was using the scientific method, which is very clear about hypotheses that have been shown to be false: they are stuffed immediately into the trash can.

Under the LNT theory, cancer rate increases with increasing doses of radiation - even at very low exposures. If you are to plot response (cancer) versus dose, you should have a straight line with a positive slope according to this theory that has been sanctified by the regulators and rule writers. Using data from the American Academy of Sciences' Biological Effects of Ionizing Radiation committee (BEIR), the slope of this line should be an increased cancer risk of 4% per gray for chronic radiation and 8% per gray for acute exposure. By knowing the "whole body" dose given by various radon concentrations, this slope can also be expressed in terms of lung cancer mortality (since that is the only place in the body where significant radon progeny reside) per picocurie per liter of air.The value of this prediction for men, without any consideration of smoking, is 4.5 deaths per 10,000 men per year for each pCi/l increase in airborne radon. Remember this figure.

Cohen's initial study took five years, cost millions of dollars, and accumulated data from homes in 1,729 counties, comprising about 90% of the U.S. population. [Because so many retirees move to California, Florida and Arizona, these data were deleted, reducing the number of counties to 1,601. This deletion, incidentally, had an insignificant effect on the results.] It considered radon data from the EPA, state agencies, and 272,000 measurements made by the University of Pittsburgh. Census data on smoking, rural-urban balance, occupations, education, housing, medical care - a total of fifty-four socioeconomic "confounding" factors (alone and in combinations with each other) were analyzed to determine if and how they affected the lung cancer rate.

The study found - as you may now suspect - a discrepancy between the LNT's prediction of lung cancer and the actual data. This has since been known as "our discrepancy," and Cohen has invited his colleagues to try to find a confounder that would explain it. He notes that unless someone can come up with a reason to put aside "our discrepancy," the LNT must be considered a false and unacceptable theory and discarded as a source for use in regulatory authority. With more than 500 of the suspected confounders and combinations thereof already eliminated, it does not look good for the LNT advocates - most of whom do not address "our discrepancy" but prefer to snub Dr. Cohen as a mere physicist, and not an epidemiologist. (Critics overlook that G.A. Colditz is a world-class epidemiologist and was co-author with Cohen on "Tests of the linear-no-threshold theory for lung cancer induced by exposure to radon" in Environmental Research, 64, 1994.)

Note and source for Figure 33: Effect of Residential Radon Levels on Lung Cancer - Each data point represents an average of eighty-nine U.S. counties. Source: Cohen, B.L. Test of the linear-no-threshold theory of radiation carcinogenesis for inhaled radon decay products. Health Physics, 68, 157, 1995.

Figure 33 is typical of the curves plotted from the University of Pittsburgh data and is one of four similar figures in the report - this one is for males without smoking's begin taken into account. The others are for males with smoking taken into consideration, and similar data on females both considering and not considering smoking. [These are available from his paper, Test of the Linear-No-Threshold Theory of Radiation Carcinogenesis for Inhaled Radon Decay Products," Health Physics, February 1995. All curves give a similar negative correlation between radon and cancer through 6 pCi/l.]

I have deleted the error bars and the "first and third quartile" curves because I don't think they'd mean much to the average reader. Cohen also had indicators of the numbers of counties for each data point on his curves ranging from 4 to 216 with an average of 88.9. These are counties, bear in mind, not individuals.

Remember the increase by 4.5 deaths per pCi/l predicted by the LNT? That is shown graphically by the dashed line on Figure 33. The solid line with a negative slope is the best fit of the collected data. It shows a minus 4.7 deaths per pCi/l. If some hypothetical man (recall our graph is of male data) had a choice between being exposed to, say, 6 pCi of radon in his house, or being exposed to none, what is the significance of this choice? By sealing his house and spending some $3,000 to $4,000 for the government-recommended heat exchangers, he could increase his risk of lung cancer by 7.5%.

Perhaps that doesn't sound like much to you (especially if we're not talking about your lungs), but it is a huge increase in risk compared even with the LNTer's worst chortlings. You may recall the BEIR statistic for chronic radiation exposure predicts an increase in risk of cancer mortality of 8% for exposure to 2 gray, which is 200 cGy or 200,000 mrem. This is far above the risk experienced by all but a small fraction of A-bomb survivors! So if you missed Hiroshima and Nagasaki, just hang in there with the EPA recommendation on radon. They'll help you reach that goal of a significant increase in cancer risk!

I like the way Jay Lehr summed up Cohen's results in an article, "Good News About Radon: The Linear Nonthreshold Model is Wrong":

"Thus, in spite of extensive efforts to find a flaw in the obvious results indicated by the observed data, no potential explanation for the discrepancy between theory and reality could be found. It therefore appears that the linear no-threshold theory for carcinogenesis from inhaled radon decay products is invalid. This is indeed good news."

It would have been even better news if more people knew about it.

[Dr. Lehr is a senior scientist with Environmental Education Enterprises, a provider of high-technology short courses for environmental professionals.]

Don't Let the Data Get in the Way of a "Made Up" Mind

What is the significance of this report? Professor Emeritus John Cameron of the University of Wisconsin Medical School puts it in perspective:

"This study is probably the best scientific evidence, of many scientific data sources, to show that low levels of ionizing radiation are without health hazard. The results clearly contradict the conclusions of BEIR [American Academy of Science Biological Effects of Ionizing Radiation committee] that even small amounts of radiation have risk (in BEIR V and earlier reports), which have been largely based on the data from the Japanese atomic bomb survivors, who largely received their radiation exposures in very brief, high dose rate conditions and who are also now demonstrating that effective radiation health effects thresholds exist in the range of 20 to 200 rem [20 to 200 cGy]."

It is commonplace for us to read various national polls in the newspapers based on 1,044 or so interviews. Presidents and tax-peasants alike make decisions from the opinions of a group of individuals that wouldn't fill one side of a high school basketball gymnasium. Yet in the United States, with a sample size of about 1,000, the statistical error is on the order of 5%. Compare that sample size with the 72,000 individuals evaluated in the in-depth scientific survey being presented here. Yet the Department of Energy hasn't bothered to explain why their own study flies in the face of their regulatory policy.

***

Permit me to elaborate on just a few points. Certainly you are welcome to draw your own conclusions from the surprising (to the researchers, anyway) Johns Hopkins data, but here are the top three things that jump out at me in response to this data:

1. Why would 28,000 workers, with the same backgrounds as the guys they stood with in the hiring line, have 24% fewer deaths than their non-nuclear buddies?

2. Except for mesothelioma, which was attributed to other causes, the exposed individuals invariably had a lower mortality than unexposed. This is precisely the opposite of what the LNT hypothesis would predict.

3. While the lung cancer rate of all workers was higher than that of the general population - presumably since more industrial workers smoke cigarettes than do coaches and preachers - it is very interesting that these data parallel others that show that the exposure of lung tissue to radiation reduces lung cancer. The alpha radiation from radon and plutonium, in particular, seems to do a good job. (No, I'm really not kidding.)

***

Get ready for a treat. You are about to meet Bernie Cohen.

Remedial Acryonyms

There are a couple abbreviations used in Table 13 and/or Figure 32 that may need reminders. SMR stands for standardized mortality ratio and compares the death rate of a group in question with that of an age-adjusted population of peers. In this study, for instance, it is seen that the Nones group has an SMR of 1.00. This means it exactly corresponds with the general population data accumulated over many years by the U.S. Bureau of Vital Statistics - just what you might expect from so large a population sample.

You should remember that the SMR has nothing to do with the number of deaths from a particular risk - just the ratio of deaths in, say, nuclear plant workers to (divided by) the number of deaths expected in individuals of similar ages and backgrounds.

LHC stands for Lymphatic and Hematopoietic Cancer, which relates to cancers of the lymph nodes and the formation of blood in the body.

A fifth cancer category was not plotted with the rest of the data in Figure 32: the SMR for mesothelioma. Table 13 indicates that both exposed groups showed more than twice the mortality of the unexposed workers. The report suggests, however, that this high ratio was due to both a low (and therefore statistically inaccurate) number of deaths from this cause, and the exposure of both radiation worker groups to environments laden with amphibole fibers - the imported, dangerous form of asbestos. (Not to be confused with the benign chrysotile variety.)

Table 13
Summary of Mortality
	NW>5	NW<5	NNW
CAUSE OF DEATH	“Highs”	“Lows”	“Nones”
All Causes	2,797	1,168	4,453
SMR	0.76	0.81	1.00
95% Confidence*	0.73, 0.79	0.76, 0.86	0.97, 1.03
Leukemia	21	4	29
SMR	0.91	0.42	0.97
95% Confidence*	0.56, 01.39	0.11, 1.07	0.65, 1.39
LHC	50	13	29
SMR	0.82	0.53	1.10
95% Confidence*	0.61, 1.08	0.28, 0.91	0.88, 1.37
Mesothelioma	18	8	10
SMR	5.49	6.14	2.54
95% Confidence	3.03, 8.08	2.48, 11.33	1.16, 4.43
Lung Cancer	237	98	306
SMR	1.07	1.11	1.15
95% Confidence*	0.94, 1.21	0.90, 1.35	1.02, 1.29
Source: Johns Hopkins Final Report, Health Effects of Low-Level Radiation in Shipyard Workers, June 1991, Table 4.1, p. 344.
*The use of 95% confidence limits is a method to show the range of statistically possible values on either side of the most probable value.

Caption for Figure 32: Summary of Shipyard Workers' Mortality: Health Effects of Low-Level Radiation in Shipyard Workers. DOE Contract Number DE-AC02-79EV10095. The Johns Hopkins University, Department of Epidemiology, Baltimore, Md. Final Report. June, 1991.

And Now the Envelope, Please...

When the data were analyzed and tabulated, there must have been a number of stunned Johns Hopkins Ph.D.s wondering what had happened. They started out to show the adverse effects of gamma radiation and ended up showing that it enhanced healthfulness.

The first page of the "Summary of Findings" tells the story:

"The all cause mortality is highest for the NNW [Nones] group and lowest for the NW>0.5 [Highs] which certainly does not suggest that radiation causes a general risk of health. In fact, in the NW>0.5 group, the mortality is only 76 percent of that of the general population and is significantly lower than would be expected."

Following these statements are eight pages of possible explanations of what may have happened to give such unexpected results. One suggestion was to use the Lows as the comparison group instead of the Nones, but even this still has the higher exposed group with the lowest overall death rate... not what was expected. An attempt to explain away the unusual with the usual "healthy worker effect" was mentioned, though without much enthusiasm. But nothing in the report even got close to explaining the numbers printed in the report under "Actual Data."

Some Background for the Study

A 1978 report raise the question of low-dose ionizing radiation risk to nuclear workers at the Portsmouth, New Hampshire, shipyard. [Identified as "Najarian, 1978" in the Johns Hopkins Report Introduction, referring to brief study done by Dr. Thomas Najarian, a hematologist at the Boston Veterans Administration hospital.]

In 1980, a U.S. Department of Energy contract was granted to the Department of Epidemiology at The Johns Hopkins University to study "Health Effects of Low-Level Radiation in Shipyard Workers." [DOE Contract Number DE-AC02-79EV10095.]

It is apparent from the introduction that this was expected to be a confirmation of the earlier "limited study" and certainly had nothing to do with verification of the hormesis principle - which it ended up being. [The term "radiation hormesis" had not even been used yet, as Luckey's first book was still a year or two away when the contract was awarded.]

The study involved an initial pool of 700,000 workers - including 108,000 nuclear workers - at two private and six government shipyards. Most were weeded out because of missing or incomplete records. Then too, many of the non-nuclear workers did not work in a shipyard during the time when nuclear overhauls were done and were therefore not considered to be comparable to nuclear workers. Two other steps - a crosscheck of records and a questionnaire to the worker or next of kin - pared the list down to 72,356 qualified subjects. Workers were divided into three categories:

1. Those with duties not involving radiation, the Non-Nuclear Workers (NNW's - or in our case, the Nones). This group of 33,352 workers was used as the control.

2. Those who had cumulative exposure of less than 500 mrem. These were termed NW<0.5, which we will call the Lows, and totaled 10,462 workers.

3. Those with cumulative exposures greater than or equal to 500 mrem. They were referred to as NW>0.5, which we'll refer to as the Highs, numbering 28,542 workers.

Results of the study were tabulated to show mortality ratios of the above cohorts from various types of cancer and from all causes. By the way, althought the Johns Hopkins report to the Department of Energy was completed nearly fifteen years ago, the Energy Department has yet to acknowledge the results and issue its report on the study.

Something's Fishy in the Shipyard

The nuclear worker groups had a lower death rate from all causes, leukemia, and LHC than the non-nuclear workers. - Professor Emeritus Myron Pollycove, M.D., University of California at San Francisco, Medicine and Radiology

Suppose you're not convinced about the concept of radiation hormesis and want to do a statistical analysis to settle the matter in your own mind. What is your concept of a "convincing" study? How would you design an experiment so that you would have no doubt about the trustworthiness of the results? Some safeguards I'd like to see would be:

1. The study would have to be supported by deep pockets, because there would be a lot of expense in collecting and analyzing the mountains of data involved.

2. I would want those in charge of the actual research (as opposed to those who are paying for it) to be scientists from a reputable institution.

3. There must be a very large number of exposed persons and the same order of unexposed controls, with both chosen randomly from the same employment pool in order to make the study statistically meaningful and to avoid any possible "healthy worker effect."

4. The doses to the individuals would have to be as accurately known as possible, at least up to industrial or military standards.

5. The study would have to look at not only cancer but also total mortality, in order to test the hypothesis that radiation hormesis not only might reduce cancer, but also might lessen the effects of infectious diseases and other immune system breakdowns.

6. Finally, I would want the researchers to believe that they were attempting to measure a positive correlation between radiation and disease, without even suspecting that any hormesis effect was of interest.

The following investigation at Johns Hopkins meets all my criteria.

A Few Snippets

Allow me to give you just a few snippets on other subjects related to both medicine and radiation:

"Court-Brown and Doll (1958) using a standard cohort technique, analyuzed the mortality of radiologists belonging to the 2 major radiological societies in the United Kingdom through 1956. Radiologists joining radiological societies after 1920 have had 176 deaths if they had the same life expectancy as the general population, or 169 death if their life expectancy was the same as that of physicians in general. Only 145 deaths were recorded." [Henry, Hugh (Oak Ridge National Laboratory). Is all radiation harmful? Journal of the American Medical Association, 16, 671, 1961.]

A study of 100,000 female radiology technicians, with a mean follow-up time of twenty-nine years since certification, showed no association for breast cancer with vocational experience in radio-therapy, nuclear medicine or fluoroscopy. [Boice, J.D., et al. U.S. National Cancer Institute risk of breast cancer evaluation. Journal of the American Medical Association, Vol. 274, No. 5, 1995.]

"A critical review of the literature leads to the conclusion that at the radiation doses generally of concern in radiation protection [greater than 2 gray (or 200,000 mrad)], protracted exposures to low linear energy transfer (LET) radiation does not appear to cause lung cancer. There is, in fact, indication of reduction of the natural incidence. [Emphasis added.] [Rossi, H. and Zaider, M. Radiogenic lung cancer: the effects of low doses of low linear energy transfer (LET) radiation. Radiation Environmental Biophysics, 36, 1997.]

Finally, there is the connection between cancer and the application of radium to watch dials, which is fairly notorious in medical texts. The women (there were only about a dozen men in this vocation) touched their tongues to their brushes while painting, thereby receiving a large internal dose. Just as in the case of H-bomb test fallout victims, I thought all the painters died early deaths from radiation-induced cancer. Perhaps the literature left you with the same erroneous impression.

"The absence of leukemia and other potential radiogenic cancers in the population of highly exposed radium dial painters - from both internal and external radiation - contradicts the LNT; moreover, the increase longevity of these workers has been noted, but competent documentation does not exist at this time." [Note: Support for study of these workers has been cancelled.] [Kondo, Sohei. (Senior Researcher, Atomic Energy Research Institute, Osaka) Health Effects of Low-Level Radiation. Kinki University Press, Osaka, and Medical Physics Publishing, Madison, Wisc., 1993.]

***

Before turning the page, consider for a moment what evidence it would take to make you a "hormesian." (Not to worry, I promise not to use that word again.)

We're Out of Copper, But How About a Zirconium Bracelet?

Among the cruelest deceptions perpetrated upon people by other people are those having to do with phony medical aids, sham healing potions, "miracle" cures, and other forms of snake oil. It just seems to be my nature to suspect the worst when even the most trustworthy appearing people suggest to me some "cure" that has somehow been overlooked by pharmaceutical manufacturers who spend a few billion dollars a year on research - but is well known to granny and the girls working down in the lingerie department. This isn't to say that it doesn't happen, but these "cures" are certainly suspect from the start with me. And so it was when I first heard about the "Free Enterprise Mine" and its claim to have a beneficial effect on arthritis, bursitis, and a dozen or so other debilitating conditions.

For starters, I didn't like the name. Not because I don't like the free-enterprise system, but because I do. It seemed to me that charlatans might be using a good name to disguise another of those despicable medical deceptions. This was early in my attempt at writing this book - and I didn't think any more about it for several months. By then I knew about the high radon content of many European spas and those at Bad Gastein in particular. To me, these resorts, which compete for having the highest radiation level, just showed that our fears of radon and low-level radiation were what I had already suspected: contrived and ridiculous.

What I didn't know was that the major "cures" offered by such health resorts ad the "Thermal Galleries" (a former gold mine and only one of the many spas in the Bad Gastein area) were for "rheumatic, arthritic and scoliotic disease." What was described in their advertisements was much like what I had heard about the Free Enterprise Mine, with one big difference: The spas had a two-thousand year history of arthritics coming there for relief. Still, the placebo effect and mass hypnosis didn't start with the twentieth century. I don't enjoy being fooled, and what's more, I didn't plan to be a shill for anyone bent on fooling others. Skepticism reigned.

Only very recently did I learn of the Japanese research on the hormonal reactions to inhalation of radon. (The test animals in these experiments were rabbits rather than mice.) As shown in Figure 31, there were marked increases in both beta-endorphins and m-enkephalins in the test animals. Those who know about such things claim that the former is a pain reliever, while the latter hormone creates a feeling of well-being.

Source for Figure 31 Effect of Radon Inhalation on Hormones: Yamaoka, K., Komoto, Y., Suzuka, I., Edamatsu, R., Mori, A., Effects of radon inhalation on biological function - lipid peroxide level, superoxide dismutase activity, and membrane fluidity. Arch Biochem Biophys. 1993 Apr; 302(1):37-41.

It dawned on me that I now had evidence from three continents leading to the same conclusion: that radon inhalation has a positive effect on arthritic diseases.

I remembered that someone had sent me a book on the Free Enterprise Mine, which I had carefully filed in the "probably won't need this" box. The name of the book was Arthritis and Radioactivity, by Wade V. Lewis, the original owner of the mine. [Available from Free Enterprise Mine, P.O. Box 67, Boulder, MT 59632. Email: hlthmine@mt.net.]

I learned that it didn't start out as any kind of treatment facility, but as a uranium mine in 1949. By chance, the wife of a visiting engineer went down in the mine with him and found to her amazement that her debilitating arthritic condition had improved. She convinced a friend in similar circumstances to return with her to see if this was "for real." Apparently it was, as the mine has flourished ever since.

The best thing about the book is its tone. It is not written in a "This is the way it is" and "This is what's happening" manner. It's more like "This is the way it appears" and "Perhaps this is the cause." The author, who died in 1974, was not a scientist but had learned a great deal about radiation and was trying to put the pieces together. If only he had had Luckey and Pollycove around at the time, it's no telling what the trio could have accomplished.

On August 27, 1999, there were a number of scientists on the way to a "Nuclear Technology - Bridging the Millennia" conference in Jackson, Wyoming. Among the speakers was Sadao Hattori, a Ph.D. in nuclear engineering who is vice-president and director of nuclear energy research at the Central Research Institute of the Electric Power Industry (CRIEPI) of Japan. Earlier, while compiling quotations from a large number of scientists (by which I hoped to show the depth of scientific criticism of the LNT and support for hormesis research), I ran across this 1996 quotation from the animated and dedicated "hormesian" [your author's first (and probably last) attempt at coining a word], Dr. Hattori:

"We [CRIEPI] are now carrying out experimental activities on the effects of low-dose radiation on mammals. After several years of research activities, we are recognizing Luckey's claim. Some basic surveys, including Hiroshima-Nagasaki survivors and animal experiments in Japan, have brought us exciting information on the health effects of low-dose radiation."

He went on to say that results for their research would be forthcoming. Let me tell you: Dr. Hattori delivers. In his paper delivered at the 1999 Boston conference of the American Nuclear Society, the nuclear scientist spoke on the following areas being explored by Japanese researchers:
1. Okumura's longevity of survivors exposed to low dose A-bomb radiation;
2. Sakamoto's non-Hodgkin's lymphoma successes;
3. Onishi's reports of enhancing the p53 tumor suppression gene;
4. An update on Mifune's Misasa Radon Spring study;
5. Yonezawa's research on Adaptive Response Windows;
6. Miyachi's work on stress moderation and pain relief;
7. Yamaoka's studies of hormonal and adrenaline increases.

There is one more study by Yamaoka with which an enterprising tabloid reporter could write his own ticket - if he could only understand a little science.

Yamaoka has found that radiation has a beneficial effect on cell membrane permeability, which in turn has a positive effect on the life of a particular cell. Stimulatory radiation equals high permeability, no wrinkles, no aging - and before this, relief from arthritis and related conditions. Rather interesting stories, wouldn't you say? Gee, I wonder where the reporters have gone.

It's Not Too Late to Radiate!

We are all aware of the use of high-energy radiation to kill cancer cells within the body. The problem has always been in not wiping out more of numerous good ones while attempting to eliminate the radiation-susceptible cancer cells. After years of experiments with nice, Dr. Kiyohiko Sakamoto is giving hormesis-level doses along with his X-ray treatment for non-Hodgkin's lymphoma. Figure 30 shows the latest update of his work.

Patients with augmentation doses - typically 10 rad (cGy) by X-ray three times a week for five weeks - had a survival rate 68% greater than the patients without augmentation. It seems odd to me that the hormetic level radiation is given after, not prior to the larger suppressive dose. But then, it's hard to argue with success.

Source for Figure 30 Non-Hodgkin's Lymphoma Survival: Sakamoto, Kiyohiko. Survival of stage I and II of non-Hodgkin's lymphoma treated local irradiation only or combined treatment of TBI [Total Body Irradiation] and local irradiation. Journal of JASTRO, Sept. 1997. An earlier report on the same subject with wider availability is: Sakamoto, K. and Myojin, M. Fundamental and clinical studies on tumor control by total body irradiation. American Nuclear Society Transactions, 75, 404, 1996.

That Temperamental Thyroid Gland

Source for Figure 29 Cancer in Patients Treated for Hyperthyroidism: Dobyns, B.M., Sheline, G.E., Workman, J.B., Tompkins, E.A., McConahey, W.M. and Becker, D.V. Malignant and benign neoplasms of the thyroid in patients treated for hyperthyroidism: A report of the cooperative thyrotoxicosis therapy follow-up study. Journal of Clinical Endocrinological Metabolism, 38:976, 1974.

Most of our organs - like our hearts and kidneys - either work or they don't. Our thyroid gland, however, either can refuse to work hard enough (hypothyroidism), or can put out too many hormones (hyperthyroidism) - either of which can make life miserable. Those who are the victims of excessive thyroxin have several choices to reduce production of this hormone: whacking away at the thyroid with a scalpel, drugging it into submission, or introducing radioactive iodine 131 into the body, which rushes directly to the gland and essentially wounds it, thus decreasing its activity. [Iodine 131 is also used both for diagnosis of thyroid function and, in the case of a malignancy, "ablating" or "burning up" the organ. The latter procedure has made thyroid cancer probably the most successfully treatable of all malignancies.]

A study by B.M. Dobyns, et al. observed the prevalence of thyroid cancer incidence in 35,000 hyperthyroid patients out to twenty years after treatment. Some 1,200 of these were treated with drugs, with another 12,000 having undergone surgical treatment. The majority, about 22,000, were subjected to very high doses of 131I - on the order of 50,000 mrem or 50 cSv. One would logically expect rampant cancer in these individuals on the basis of the LNT. But it's (another) miracle! As Figure 29 indicates, not only did radiation not result in a high malignancy rate, but it seems to have had a hormetic aftermath. Gee, perhaps this can be explained by the "healthy patient effect."

Keeping Abreast of the Evidence

Breast cancer is a pretty depressing matter. An estimated 44,300 women (and several thousand men) will die of breast cancer this year. It is second only to lung cancer as a cause of cancer death among women. Increased use of mammography is one of the reasons for the decline in death rates. In 1992 (the most recent statistics I could find), 67% of women over forty reported having at least one screening - up from only 22% in 1979.

But sadly, many women are still hesitant to have regular mammography examinations, often because they fear that X-rays from the mammograms will increase their chances of cancer. Doing their own risk assessment, they conclude the risk from "late detection" is less than that from radiation. And who is to blame them, in light of the commonly accepted dictum that all radiation is dangerous and cumulatively so? Besides, it costs time and money to have a mammogram - at least worrying about cancer is cheap.

"So," you say, " they should just consult a professional and ask about the dose they will receive from the mammogram and make the decision on that basis." Not as simple as that may sound. In researching this chapter I called four local mammography clinics with what I thought was a pretty simple question: "What is the dose of radiation received by a woman in the process of having a mammogram?" I had seen a figure before, but it seemed high to me.

I spoke with two mammography technicians and one nurse who relayed messages from their radiologists. The unanimous answer: "We don't know." One of them, however, was kind enough to put me in touch with a local health physicist, who said the dose was "negligible" - but, even better, offered to lend me some of his reference books. In one, I was able to find the range of exposures to a "gland" (their quotation marks) at a dept of 3 cm to be 0.04 to 0.49 cGy (40 to 490 mrem), which was consistent with the 0.15 cGy figure I had found earlier and was trying to confirm.

But the information I had was perplexing, as it mentioned the dose as 150 mrem per breast. It was much like the confusion I had when learning that radon gave an exposure of 24,000 mrem/year to the bronchial epithelium (which, of course, you now know is the windpipe). The borrowed volumes were quite illuminating, I found there is an official weighting factor that, when multiplied by the local dose gives the effective dose equivalent. And what does this tell you? It tells you the increase in your chances of contracting cancer if the Linear No-Threshold theory were true!

Using a weighting factor of 0.15 for each breast, a 150 mrem per breast exposure would be an equivalent "whole body" exposure totaling 45 mrem (0.045 cSv). [Exposure of the U.S. Population from Diagnostic Medical Radiation, NCRP Report #100, National Council on Radiation Protection and Measurements, Bethesda, Md.]

The figure - in my opinion - means nothing, but if we pretend it is accurate we can use it as a starting point for a "conventional" analysis.

Published in the New England Journal of Medicine in 1989, an investigation by A.B. Miller and associates charted the doses received by 31,710 women who were irradiated in the course of repeated fluoroscopic examinations between 1930 and 1952. [Miller, A.B., et al. Mortality from breast cancer after irradiation during fluoroscopic examination in patients being treated for tuberculosis. New England Journal of Medicine, 321, 1285, 1989.]

In this Canadian study, one group - in Nova Scotia - was fluoroscoped facing the X-ray source. This results in a dose to the breast approximately twenty-five times that when faced away. The women facing the source had a significant increase in cancer risk - it tripled for each 100 cGy (100,000 mrad) of radiation absorbed.

Source for Figure 28 Incidence of Breast Cancer Death Following Fluoroscopic Examination: Miller, A.B., Howe, G.R., Sherman, G.J., Lindsay, J.P., Yaffe, M.J., Dinner, P.J., Risch, H.A., and Preston, D.L. Mortality from breast cancer after irradiation during fluoroscopic examination in patients being treated for tuberculosis. New England Journal of Medicine, 321:1285, 1989.

The balance of the study was for all other provinces, with the results presented in Figure 28. Before going on, please remember that a normal annual U.S. background dose is 0.3 cGy, with the first data point on the graph at 5 cGy - about thirteen times this amount. The minimum mortality rate is at a value fifty times the annual background dose or the equivalent (using their figures) of 100 mammography exams.

On the basis of this evidence - which is almost certainly conservative, since the dose rate for fluoroscopy is much higher and, therefore, considered more traumatic to the breasts than present mammography techniques - women should have four or five mammograms per year.

Does that sound strange? That's nothing compared with the most unusual aspect of the study, namely its conclusion: The authors completely ignored the most statistically significant data points in the entire investigation, namely the 34% reduction in relative risk at 15 cGy and the 15% reduction at 24 cGy. Myron Pollycove, M.D., remarked regarding this omission:

"The decreased RR [risk rate] of breast cancer produced by low dose, low level radiation were rejected a priori by the choice of mathematical models that extrapolate the dose-risk relation from high dose exposures to low dose exposures."

[We met Dr. Pollycover back in Chapter 2. But since he is such an important player in the LNT controversy, allow me to remind you that he is professor emeritus in Laboratory Medicine and Radiology at the University of California at San Francisco, head of Nuclear Medicine at San Francisco General Hospital, as well as a visiting medical fellow on the Nuclear Regulatory Commission.]

To most of us that simply means the researchers, for whatever reason, chose to "spike" all results that indicated hormesis. Why? Probably because they were not even considering bio-positive data; they were looking for harmful effects... period. Pollycove continues:

"Nine hundred excess deaths from breast cancer are predicted theoretically from the exposure of one million women to 0.15 Gy. However, the quantified low dose data predicts with better than 99% confidence limits that instead of causing 900 deaths, a dose of 0.15 Gy would prevent 10,000 deaths in these million women."

Pardon me, but do you understand what this man - who has possibly the most impressive credentials in this entire debate - is saying? He is proclaiming that there is unmistakable evidence of hormesis in this study, which, if acted upon, might be developed into an effective weapon against breast cancer in millions of women, thousands of whom will die needlessly because of a theory that was never intended to apply to low-level radiation! It is a pity, a shame, a disgrace that the current ingrained reliance by regulators on the Linear No-Threshold hypothesis makes even a consideration of studying the hormesis phenomen extremely difficult, if not impossible.

Take Two Cobalt 60s & Call Me in the Morning

If we really believed in the LNT, we would have to conclude that routine use of X-rays for medical purposes would cause 100,000 deaths each year. - Richard North, Alpha, 1997

Radiation and cancer are certainly strange bedfellows.

On the one hand there is a great deal of misplaced concern that the almost infinitesimally small emissions from nuclear power plants will cause widespread cancer and induce Farmer Jones's cow to give birth to two-headed calves. Yet when Farmer Jones contracts cancer (no doubt as a result of the power plant), one of the primary treatments is to destroy the cancer cells (which are unusually susceptible to radiation) with X-ray treatments or by implantation of radioactive "seeds" in the cancerous organ. And when Mrs. Farmer Jones has a hyperactive thyroid, she ingests enough iodine 131 to give her body 200 times the radiation dose - in about three weeks - that she receives over her lifetime from the natural background, to to mention the gamma radiation given to her good farmer husband from being next to him in bed. Furthermore, when little Billy Jones is found to have a fatal, inoperative brain tumor, the least invasive treatment is the "gamma knife" - a method of focusing 201 small gamma sources, which, individually, are too weak to cause any harm to anyone but the most fervent anti-nuke. Yet when they are concentrated on the offending growth together they have the power to vaporize it... and Billy goes home that afternoon completely cured. Is that a miracle or what?

However, we are not going to discuss this type of radiation therapy, since it involves the transfer of considerable amounts of energy to tissues - particularly tumors or cancers - in an attempt to destroy them or reduce their functionality. Instead, we will be concerned about the effects of comparatively tiny amounts of radiation whose purpose is to provoke the immune system into stepping up its action on the cellular level.

You may note in this chapter that virtually all of the current experimental activity mentioned is occurring in Japan, where the work of Dr. Luckey is revered - since, I suspect, it explains so much of what is happening to bomb survivors. But he Japanese have taken the matter much further, including hormetic augmentation of high-level therapies and measurement of the physiological reactions to radiation - including one that gives credence to an unusual treatment for arthritis that dates back to Roman times.

United States (again)

"Studies of populations chronically exposed to low-level radiation, such as those residing in regions of elevated natural radiation, have not shown consistent or conclusive evidence of an associated increase in the risk of cancer." [This statement conflicts with the conclusions of the report.] [From the Executive Summary, Carcinogenic Effects. Biological Effects of Ionizing Radiation Committee (BEIR) of the National Academy of Science, Report V, 1990, p. 5.

In a study of 900,000 U.S. residents with various levels of radium in water supplies, the BEIR was confounded by finding more bone cancer in Chicago - with only 1 mBq/l - than in the areas where the level exceeded 110 mBq/l. [From BEIR IV, Health Risks of Radon and Other Deposited Alpha Emitters, National Academy Press, Washington, D.C., 1988.]

A multivariant examination of forty-three urban populations of the United States showed a statistically significant negative correlation [more radiation, less cancer] between total cancer mortality and background levels of ionizing radiation. [Hickey, R.J., et al. Low level ionizing radiation and human mortality; multi-regional epidemiological studies. Health Physics, 40, 625, 1981.]

England, Finland and Germany

Mineral collectors have found places near the Cornish town of St. Austell where the background level reaches 4.3 mrem per minute (37,700 mrem or 37.7 cGy per year) according to the London-based Nuclear Issues. Cornwall and Devon have a cancer incidence well below the British national average. [Beckmann, Petr. Access to Energy, 19, 2, 1991.]

"Conclusions: Our results do not indicate increased risk of lung cancer from indoor radiation exposure." [Auvinen, A., et al. Indoor radon exposure and risk of lung cancer: a nested case-control study in Finland. Journal National Cancer Institute, 88: pp. 966-72, 1996.]

"The observed lung cancer rates of females in high residential radon areas in former uranium mining areas of Southern Saxony are substantially lower than the population average of East Germany. Thus the data from various countries, showing biopositive effects of increased radon levels, can be confirmed in an area which has been closely associated with the history of radiation health effects." [Statement by Schuttmann, W. and Becker, K. (of the German Standards Institute), 1998. Reported in Low Level Radiation Health Effects: Compiling the Data. Muckerheide, James, ed., Radiation Science and Health, Inc., Needham, Mass., Chapter 1.2.6.3., pp. 1-2.]