Why toxicologists resisted and radiation geneticists supported EPA’S adoption of LNT for cancer risk assessment

Paper Via Junk Science

Edward J. Calabresea,*, Robert J. Golden School of Public Health and Health Sciences, Department of Environmental Health Sciences, Morrill I N344, University of Massachusetts, Amherst, MA, 01003, USA b702 Linslade Street, Gaithersburg, MD, 20878, USA

ABSTRACT

The linear non-threshold (LNT) dose response model for cancer risk assessment has been a controversial concept since its initial proposal during the 1930s. It was long advocated by the radiation genetics community in the 1950s, some two decades prior to being generally adopted within the chemical toxicology community. This paper explores possible reasons for such major differences in the acceptance of LNT for cancer risk assessment by these two key groups of scientists.

1. Introduction

The US Congress passed, and President Richard Nixon signed into law the Safe Drinking Water Act in 1974. A significant provision of the Act involved engaging the US NAS to advise the EPA on multiple scientific and technical areas such as chemical and radiation risk assessment, including cancer risk assessment. To achieve these goals the NAS created the Safe Drinking Water Committee (SDWC) in 1975. In 1977 the SDWC published the 700 page Drinking Water and Health [1] report offering EPA widespread guidance, including cancer risk assessment and its underlying scientific foundations that supported the LNT. Within two years EPA would issue the first national drinking water standard for a chemical carcinogen using the LNT for total trihalomethanes (THM) [2]. This action would jump start an avalanche of other LNT based cancer risk assessments by EPA, not just for drinking water but for other environmental media as well. The decision to go linear by the SDWC for chemical carcinogens was therefore as highly significant as it was precedent setting, and led the way for future EPA cancer risk assessment actions. The actions of the SDWC to recommend LNT for chemical carcinogens was more than two decades after a similar recommendation of the 1956 NAS BEAR Genetics Panel to switch from a threshold to LNT for radiation induced mutation.This action of the BEAR Genetics Panel was soon followed by a recommendation of the National Committee for Radiation Protection and Measurement (NCRPM) to generalize the LNT concept to somatic cells for cancer risk assessment. This two decade time gap in the decision to go linear for cancer risk assessment for ionizing radiation and chemical carcinogens suggests the possibility that chemical toxicologists and radiation geneticists/cancer researchers may have evolved considerably differently with respect to the concept of cancer risk assessment, prompting the present paper.

Read the full paper here

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72 thoughts on “Why toxicologists resisted and radiation geneticists supported EPA’S adoption of LNT for cancer risk assessment

  1. A fairly short, if dense, supporting article. The situation is rather worse, judging from the article, than I had concluded from casual study of the issue. LNT is based on what must me some other consideration than observed results, as none of the animal or human epidemiology studies support the Linear/No Threshold model.
    But the math to come up with scary “predictions” is fairly easy, so LNT gets used anyway. It also yields the worst outcomes claimed.

    • The LNT is based simply on the potential to cause DNA damage, a spot of damage. The flaw in the assumption underlying the LNT is that it wrongly assumes DNA damage equals cancer. We know today there are a host of repair mechanism that fix this damage. Second, the immune systems ability to destroy aberrant cells was underestimated. Lastly, a potential cancerous cell must be promoted in order for it to become a tumor. So while the LNT is correct, even from a toxicological view, that a single molecule can potentially form the DNA damage necessary to create a cancer cell, that is pretty much where the story ends. The cancer process is way more complicated than just DNA damage.

      • It also ignores the fact that all life on earth, humans included, have evolved biological mechanisms to deal with DNA damage. We are bombarded with DNA-altering radiation every second, causing lots of cellular damage, yet most of it never results in injury or death.

        This MIT study of low-dose radiation found amounts up to 400 times the background level were tolerated with no apparent ill effects:

        http://news.mit.edu/2012/prolonged-radiation-exposure-0515

        • May be true, but I think going from limits of 5 Rem/yr to between 40 and 120 Rem/yr might be a hard cell.
          (Background being about 100-300mr/yr.)

    • The effective purpose of LNT is to leverage infinitesimal odds to large populations and come up with an integer death count. Then you show stock photos of babies and other people with vague or no caption, to give low information readers the insinuation that ‘these’ died.

    • This action would jump start an avalanche of other LNT based cancer risk assessments by EPA, not just for drinking water but for other environmental media as well.

      “YUP”, for population control, political payback and taxing purposes, …… government entities create a fictitious “claim” along with the “fuzzy” math to support their scary “predictions.

      Nuclear war in the 1950s, ….. cigarette smoke and nuclear reactors in the 1970s, ….. etc., etc., …. CAGW in the 2000s.

  2. The paper’s conclusions indicate the decision to institutionalize LNT was as much debatable politics as it was debatable science. Does this sound familiar, ‘Climate Change’ advocates?

    • It sounds similar to WHO’s finding of a carcinogenic pattern in glyphosate-based Roundup and the juries ruling for a single case of a man who ingested the herbicide and a potential link to his condition.

      It sounds similar to the prophets of catastrophic anthropogenic global warming, who with liberal license inferred the behavior of a reaction characterized in isolation to global proportions and with progressive (i.e. monotonic) consequences.

    • It sounds similar to the injustices visited by social justice activists who with liberal license indulge in diversity (i.e. color judgment) and affirmative discrimination backed by statistical inference from models that purport to capture and predict human interest and intent.

  3. “Over 3,000 scientific research papers show that low dose irradiation is stimulatory and/or beneficial in a wide variety of microbes, plants, invertebrates, and vertebrates (Luckey, 1980a, 1991, Muckerheide, 2001). Using the parameters of cancer mortality rates or mean lifespan in humans, no scientifically acceptable study was found which showed that less than 10 cGy was harmful. Radiation, Science, and Health, Inc. (Box 843, Needham, MA 02494) offers $1,000 for one report in English with scientifically acceptable evidence of harm (increased cancer death rate or decreased average lifespan) from low dose irradiation in normal (not immune deficient) humans or laboratory animals. This is opposed by several thousand studies which produced confirmed and definitive evidence of stimulation and/or benefit.”

    From the reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2477686/

    • I pondered the “stimulation and benefit” aspect of low dosage nuclear radiation years ago when papers on the health risks were finding that nuclear workers were statistically a healthier group with longer lives than comparable populations. On the Chernobyl article I pointed out that the e-folk search engines seem to have deep-sixed links to studies on beneficial aspects of low dose nuclear because I couldnt find a link.

      Doug Huffman responded with a link to a study of groups of shipyard workers certified for handling nuclear stuff. The study found this surprising benefit to the health of this group. It is also well known to geochemists and agronomists that plants have an affinity to drawing in radioactive “nutrients”. It can even be used in exploration for uranium (sample new growth twigs, ash them and assay for uranium, searching for areas of elevated U).

      Moreover, phosphate deposits used for making fertilizers are notoriously elevated in U, Ra and Th, particularly U (in processing radium reports to the tailings, but uranium reports to the phosphate products.) Some processors recover a bit of U as a byproduct, but still, fertilizers do contain some, and plants love it! You can’t avoid radiation at least of low dosages. Granites, sandstones and other geological units covering vast area are naturally radioactive as is your granite countertops, building exterior walls, floors, elevator facies, etc.

      I came to wonder if nuclear radiation is not perhaps the acrual engine of evolution. Imagine the huge natural experiment where mutations can be generated randomly and the most useful one get to prevail. Now there is something for Intelligen Design folks!

      BTW, a central, accessible depository of scientific papers on subjects deemed ‘unhelpful’ to the sinistral worldview establishment should be maintained by groups worried about the manipulation of science. Google is ‘not’ your friend.

      • “I pondered the “stimulation and benefit” aspect of low dosage nuclear radiation years ago.”

        “Granites, sandstones and other geological units covering vast area are naturally radioactive as is your granite countertops, building exterior walls, floors, elevator”

        This sort of stuff is manifest nonsense.
        It all depends how the radiation is ingested or administered, what isotopes are involved and the dose rate and at what energy.
        The usual commentaries follow, blind generalisations including the marvellous stimulatory & healing power of ionising radiation!

        WTF!
        I feel like being back in 1919 not 2019, with the “radium girls”, Marie Curie, X rays for health et al.

        Fact is, if you combine the effects of several powerful carcinogens you get an elevated risk of cancer, whether it’s airline staff, mil personel exposed to large doses of old DU dust, uranium miners (now subcontracted to Africa, rather than NIMBY mainland France..) or living in Brittany with high nitrate pollution in the ground water.

        In Eastern Europe, heavy smoking, drinking, and high levels of radiation are combined under the same roofs in many cases.
        Fact is,- bad health and cancer go hand in hand in an often fatal embrace coupled with low almost suicidal self esteem.

        I simply cannot understand how in this day and age people could possibly believe more radiation is better.
        It’s mediocre quackery at its worst!

        • I simply cannot understand how in this day and age people could possibly believe more radiation is better.

          Then read all of the above comments again. There is good statistical evidence evidence for it, and there are DNA-repair mechanisms which provide a plausible mechanism for it.

          One can also argue that because we evolved with background radiation (possibly higher in the past) then our biology is most comfortably adapted to its many effects, which are still not well understood. But just because you personally cannot believe something, that doesn’t mean that it is false.

        • pigs in space: strawman arguments are ideological tools. You know that don’t you. Also throwing in smoking and other confounders. Your argument is fine. I accept it. But it wasn’t what I was talking about. I specifically said Low Dosage. Low dosage aspect is extremely difficult to argue isn’t it? How about:

          Do you know strychnine is a poison, but also heart attack medicine? It saves lives. Do you know vitamin D is a deadly poison that we would die without? Polar bear livers are so loaded with vitamin D that you will kill yourself eating it. A small piece (dosage) is spectacularly beneficial though. Do you know a lethal dose of milk will kill you? Do you eat bananas or avoid them like the plague.

          Your contributions are usually more thoughtful than this.

          • Mr Pearse,

            I suspect you mean Vitamin A.

            (There’s a story of an Antarctic expedition that lost their food in a crevasse, but made it back to base eating the dogs. They thought they were suffering from frostbite and malnutrition. It turned out they were getting Vitamin A poisoning from the livers.)

        • “I simply cannot understand how in this day and age people could possibly believe more radiation is better.
          It’s mediocre quackery at its worst!”

          It is not so much that more is better, (although there is evidence that is actually true). The issue for me is that once again models and projections are used to make a political agenda and policy changes. And that these models are neither verified or proven. They are just convenient props.

        • I suggest you look at studies by Cohen (University of Pittsburgh) regarding cancer occurrence relative to areas with elevated natural radiation (radon) which indicate a inverse relationship. Seems to fly in the face of the LNT argument.

          • I don’t care what Cohen says,
            I live in one of the highest atmospheric Radon areas in the world.

            It also got showered in Radio-caesium in 1986 which entered the food chain from our friends in Ukraine.

            It’s quite spectacular the high radiation levels during winter month when all the doors and windows are closed (can be -25C outside with 1m of snow).
            I have photos of my meter showing easily 0.4-0.5mR/hr indoors.

            It also happens that people smoke a lot and work in the local brick factory where people handle uranium and thorium impregnated clay with their bare hands then cook it in ovens and create mountains of radioactive dust, and smoke a lot.

            The stuff is in the ground water, and gets fed to your pets.
            Primary cause of death in the area.

            LUNG, THROAT & BOWEL CANCER

        • Dr. Luckey spent his life gathering STATISTICS, not hearsay, on the effects of low dose radiation on atomic bomb survivors in Japan, Uranium mine workers, Taiwanese tenants that lived for years in (Co60 contaminated ) steel concrete buildings, etc. Add to that over 100 years of (still active) Radon baths experiences in Austria, Czech Republic and Russia plus the slightly increased life expectancy of endangered animals released into the Tchernobyl no-go zones and the absence of mutations in their offspring. In Ramsar, Iran the people born there should die shorty after birth (according to LNT model) because their environment is highly radioactive due to uranium/Radium present in their natural environment. Yet they have the same life expectancy as the rest of that country. Their cells, when bombarded in lab environment with ionizing radiation show a resilience compared to cells from other people.

          The science is overwhelming, that low dose reduces cancer risk and extends life span. Why that is so, e.g. immune responses etc. is a different question. Fact is, “nature is non linear” and radiation damage is non linear at med to low doses. The problem with trying to use low doses in therapy is that some people e.g. cancer patients who were exposed to radiation treatment are more radiation sensitive than others.

        • When farmers went to the field and took their babies with them, they laid the child under the shade of a tree with a cloth filled with arsenic-containing earth into it’s mouth, so that the child would calmly sleep in the morning.

          The poison is in the dose.

  4. The take-home message from the paper is this: “The adoption of LNT [Linear No Threshold] by the radiation geneticist community occurred without the assistance of animal model cancer research, in fact, it required ignoring the consistent nonsupportive animal model study conclusions. (my bold)”

    It’s the usual business of a self-interested group forcing a conclusion that is not supported by the available data.

    That seems to be a mistake that changes its stripes with every subject (e.g., LNT, AGW, GMO, social constructivism), and so is endlessly repeated.

  5. On the origins of the linear no-threshold (LNT) dogma by means of untruths, artful dodges and blind faith.
    Calabrese EJ

    Abstract
    This paper is an historical assessment of how prominent radiation geneticists in the United States during the 1940s and 1950s successfully worked to build acceptance for the linear no-threshold (LNT) dose-response model in risk assessment, significantly impacting environmental, occupational and medical exposure standards and practices to the present time. Detailed documentation indicates that actions taken in support of this policy revolution were ideologically driven and deliberately and deceptively misleading; that scientific records were artfully misrepresented; and that people and organizations in positions of public trust failed to perform the duties expected of them. …

    https://www.ncbi.nlm.nih.gov/pubmed/26248082

    See also Richard Rhodes’ Energy: A Human History

  6. This looks like the killer sentence. Note that, as usual, it involved modeling:….

    “……….The LNT debate was eventually won by the EPA and its LNT supporters with the assistance of an overpowering influence of low dose biostatistical modeling perspectives that swayed the quantitatively overwhelmed chemical toxicologists…………”

  7. This looks like the most important sentence. Note that, as usual, the decision involved modeling:….

    “……….The LNT debate was eventually won by the EPA and its LNT supporters with the assistance of an overpowering influence of low dose biostatistical modeling perspectives that swayed the quantitatively overwhelmed chemical toxicologists…………”

  8. I’ve skimmed the first few paragraphs of the report and it reveals to me a history of the LNT theory I didn’t know existed.

    About a decade ago, in the UK, our BBC Horizon programme (this was BSC – before scientific correctness, pre Attenborough, pre the whole clanjamfrie of modern science) ran a whole hour on the subject. This first part of this explored understanding the effects of low doses of radiation, early X rays, ‘for a healthy glow drink radiation’, shoe fitting machines, that sort of thing. Then they reported a detailed analysis of what was learnt from the Japanese bombs. There measurements solidly confirmed the LNT theory, with cancer occurrence clearly related to experienced dose varying along a straight line that passed through zero.

    Then the lessons of Chernobyl were explored. Here, the range of exposures was dominantly below those in Japan but the occurrence of cancers did not follow the LNT theory. There were too few, far too few, cancers. And since the programme ran more than 25 years after Chernobyl, the radiation induced cancers should have ‘tolled’ by then.

    There was conjecture in the Horizon programme that the LNT theory needed changing, departing from passing though zero and observing a point where low exposures were of no consequence. There were demonstrations that this would be unharmful since there were already communities (in mountainous Iran, for example) already experiencing such low doses with no harmful effects. So this weakness of LNT theory has been long known.

    Does this make any difference? If we applied an accurate LNT equation would we save money? The company I worked for in the UK (in the 70s) already knew the LNT was flawed but ignored that position. They followed LNT. Basically, it didn’t matter to them: LNT was easy enough for compliance. I think that remains the position, certainly for the nuclear generation industry.

    But: are we following LNT in the Chernobyl and Fukishima contamination zones, an thus following PSC hysteria? There, compliance with a correct theory could make a huge economic and social improvement.

    • “Then the lessons of Chernobyl were explored. Here, the range of exposures was dominantly below those in Japan but the occurrence of cancers did not follow the LNT theory. There were too few, far too few, cancers. And since the programme ran more than 25 years after Chernobyl, the radiation induced cancers should have ‘tolled’ by then.”

      I find it remarkable that people would think that comprehensive, accurate information would necessarily be forthcoming from the USSR. As mentioned by someone on a previous thread, victims were scattered all over the soviet union, and we don’t know what happened to them (like the women he spoke to whose hair was falling out). And as mentioned in an article I linked to, the managers of a wool processing factory, of which around 200 workers were given liquidator status because the wool they handled was so radioactive, didn’t report things to Moscow because they didn’t want to create problems.

      • In your case, then, there’s no proof either way, unless you are furnished with a epidemiological study which you deem politically acceptable.

        I was swayed by the studies reported by the Horizon programme.

  9. Here’s a link — https://luysii.wordpress.com/2018/12/05/is-a-little-infection-good-for-you-if-so-what-about-radiation/

    There is a lot of introduction, but read to the end where hormesis by Calabrese is described. It’s not just a no threshold model, but one that says exposure in small doses to an adverse agent actually is biologically good.

    Could a little infection be good for you? Well how about the immune stimulation it produces? We’re talking about trained immunity here, and evidence for it started nearly 100 years ago in northern Sweden. TB was a much bigger problem back then (Hell, my grandmother died of undiagnosed tuberculosis in a university hospital in 1967). Bacille Calmette Guerin (BCG) is an attenuated form of mycobacterium tuberculosis (TB to you). Immunizing with BCG was thought to be protective against TB. 100 years later people are still arguing about it.

    What no one is arguing about is the fact the unvaccinated infants had a 10% mortality in the first year of life (the good old days weren’t that good), while the vaccinated ones had a 3% one year mortality. The 10% that did die, didn’t die of TB either.

    It’s pretty technical, but basically BCG vaccination jazzes up the immune system, making it more responsive to the zillions of critters infesting us. [ Proc. Natl. Acad. Sci. vol. 109 pp. 17537 – 17542 ’12 ] has the details — inferferon gamma, monocyte derived cytokines, the NOD2 receptor, histone 3 lysine 4 trimethylation etc. etc.

    These are rather nonspecific features of innate immunity, and not specifically directed at anything in particular (which is why it is called trained immunity).

    Well infection jazzes up the immune system too. Cell vol, 175 pp. 1634 – 1650 ’18 showed that white cells of mice found in the lungs (alveolar macrophages) developed it after a viral infection, making them more resistant to a subsequent bacterial infection. Could this be general?

    Which brings us to a much larger fish to fry –hormesis.

    Toxicology basically had two models of how we deal with toxic agents

    l. Threshold model — below a certain dose, no harm results. Arguably true — can one molecule of anything kill you? Used by the EPA for nonCarcinogens

    2. Linear no-threshold model — now matter how lot the dose, damage is seen. This is obviously crazy (see #1 above) but apparently is used by the EPA for carcinogens.

    Enter model #3 — Hormesis

    The best example is the famous J curve for alcohol in which small amounts are beneficial at low doses for the heart and huge amounts are horrible (although a recent meta-analysis has challenged this [ Lancet vol. 392 pp. 1015 – 1035 ’18 ], but I don’t trust them — for why see http://science.sciencemag.org/content/sci/361/6408/1184.full.pdf.

    Hormesis says that other toxic agents (radiation, cadmium, dioxin, saccharin, polychlorinated biphenyls) all have J curves like alcohol. Articles explaining hormesis can be found in — Nature vol. 421 pp. 691 -692 2003, Scientific American 9/2003. The reaction to it — Science vol,. 302 pp. 376 – 379, 2003.

    So the moral might be don’t be an immunological or a toxicological snowflake — that which doesn’t kill you makes you stronger.

    • Salt also may have a J curve. Low salt is bad for you as is high salt. There is controversy about this mainly becasue of the differences in people. I lean toward the J curve.

      • Bill T,

        to digest salt filled in glasses will do no harm. Even if accepted from tongue or palate, tongue or palate in the follow will demand sufficient clear water – the body is not a chemistry lab but it responds promptly to taste and will demand sufficient clear water.

        Rinsing with clear water prevents the formation of gallstones.

  10. I hate to say it, because I am eating a banana for the potassium, but Linear No Threshold means the radioactive K40 in the banana rules it out. This whole LNT idea is loco, but why not even a risk-reward analysis? I hate to think my banana will turn out to be contraband and I need to buy if from some shady character on a street corner!

    • Ron Long
      “… some shady character on a street corner!” More likely out the the trunk of a car (‘boot’ for our British relations) near a school yard.

      • Here in Indiana buying Fruit from the back of a car or truck on a street corner isn’t even that odd.

        ~¿~

  11. The ‘a’ threw me, as Calabrese has been a main proponent/explainer of hormesis, some links noted above. [Calabrese, E. J. 2008. Hormesis: why it is important to toxicology and toxicologists. Environmental Toxicology Chemistry. 27(7):1451-1474.] The last Toxicology book (a recent one) I examined still lists hormesis as “controversial.” It is, if I recall correctly from his work, a complex of different systems, not that it is possibly close to being universal. I have read some of his impressive work, and others, as hormesis in some form or another crops up in a lot of ‘non-toxicological’ places. I saw an example decades ago and didn’t know what it was.

    Here we go again as so many noted from the end of the paper–“The LNT debate was eventually won by the EPA and its LNT supporters with the assistance of an overpowering influence of low dose biostatistical modeling perspectives that swayed the quantitatively overwhelmed chemical toxicologists.” DNA is so successful in part because can not only tolerate but exploit so many “toxic” elements. Somehow this dropped out of biological education.

    • This is also important in the paper, especially since “…it required an administrative fiat…” A lot of that happened. —“The EPA would also seek to obtain support for their actions from prestigious NAS committees such as the SDWC. With respect to the USNAS SDWC, once the LNT perspective was agreed upon by the radiation geneticists and chemical toxicologists, the SDWC then constructed a theoretical foundation of eight“principles”that guided/justified their newly acquired belief in the validity of the LNT model (Table 1). These eight principles, which were published in Drinking Water and Health (1977), have not withstood the test of time well, with most being found to be incorrect and others simply not possible to prove.”

      I do not recall the 1977 reference but I would be surprised if they relied on this which has been an exceptionally valuable source to me since [Warren, C. E. 1971. Biology and Water Pollution Control. W. B. Saunders. 434p]. A student ran off with my copy which I finally replaced. It was apparently replaced by all these “Environmental Science” sorts of texts which I could never justify class use because of the politics. I once told that to a bookseller of one, reply was that they had already heard that.

      Warren came from the school of scientists that solved our real water pollution problems, one he cites “in collaboration with Peter Doudoroff.”

  12. Background radiation varies with elevation (cosmic rays) and with the bedrock composition (alpha, beta, and gamma radiation from decaying radioactive elements). The Center for Disease Control (CDC) publishes cancer mortality maps by Health Service Area, which is generally a finer resolution than counties.

    Two approaches might be explored: 1) using digital image processing software to determine the correlations between a US digital elevation model and the various digital CDC cancer mortality maps, and 2) determine the correlations between a map created by the US Geological Survey displaying background radiation and the aforementioned CDC maps.

    I’m unaware of either having been done and published. However, having seen the maps described, I’m of the opinion that little or no correlation would be demonstrated. Once again, those arguing for an ideologically-based science answer seem not to have tried simple and obvious experiments to support their position.

    • I agree that if one were able to map background/cosmic exposure over cancer risk, there would likely be either no correlation or a negative correlation for most geographic areas.

      However, people are so mobile these days it would likely overwhelm any real correlation you might find. If you could only map those people who lived in the approximate same area all their life, then you might get a realistic picture (air travel might also taint the data unless somehow accounted for). I doubt seriously the existing data is up to the task of these measurements (meaning someone would “correct” the data and get whatever result they are biased for).

      It is my guess that background radiation is such a tiny risk you wouldn’t be able to see it. It is just possible there is a reverse correlation – background radiation up to a point might be beneficial.

    • Clyde S – The current solar Grand Minimum should be increasing our cosmic ray dosage for a few years, providing a new, higher background level for us all. One would hope that the CDC will use this once in a lifetime opportunity to check the accuracy of their cancer mortality maps.

    • Yep just a quick look at you maps and data, one would conclude exposures to background radiation in the environment lowers cancer risk. Also there must be other factor at work, such as life style.

  13. Muller, and his irradiation of fruit flies, causing genetic changes ,also played a large role in this travesty.

  14. The LNT model was
    adopted relatively early by many in the radiation community, based on assumed X-ray induced gene mutation and the LNT-single hit model. Linearity for mutation became more convincingly integrated with
    human radiation induced cancer risks following the 1957 paper of Lewis in Science, with this perspective receiving an influential endorsement by the editor in chief [44]. The adoption of LNT by the radiation geneticist community occurred without the assistance of animal model cancer research, in fact, it required ignoring the consistent nonsupportive animal model study conclusions.

    This is exactly the same story as CO2 warming.
    It all goes back to Karl Popper and inductive versus deductive science.
    Radiation biology saw fit to base acceptance of LNT on a model only, any need to confirm it with experiental or epidemiological data clearly did not even cross their minds.
    Thus, according to Popper, it’s inductive junk.
    “There are no inductive inferences.”
    Here the toxicologists work by deduction (it’s toxic if we find by experiment that it is toxic).
    The “radiation biologists” work by induction (here’s our model, to hell with reality).

    The motto of toxicologists is:
    “The dose is the toxin”.
    Many substances are safe or even beneficial at low doses, but toxic at high doses above a threshold.
    Like caffeine, and all pharmaceutical drugs.
    Radiation carcinogenesis has a clearly are repeatably demonstrated threshold:

    https://www.karger.com/Article/Abstract/22024

    https://www.rrjournal.org/doi/abs/10.1667/RR3120

    https://www.rrjournal.org/doi/abs/10.1667/RR3120

    https://www.rrjournal.org/doi/abs/10.1667/0033-7587(2003)159%5B0320:LDORIT%5D2.0.CO;2

  15. Hiroshima was a city of 350,000 people when, on August 6, 1945, the first atomic bomb detonated. Today, there are 183,000 survivors with an average age of 80 years. Linear Non-Threshold radiation cancer risk might be assessed from these human data. Pretty awesome, eh?

    • Linear Non-Threshold radiation cancer risk might be assessed from these human data.

      It is. The massive project of following up the bomb survivors for life, which is still ongoing as you say, forms the backbone of epidemiology data used for radiation protection. But the linear assumption was extremely crude, just taking elevated cancer risk at large doses in the Gray range, and extrapolating down to zero with a ruler.

  16. A simple point. from a simple sort of guy (me).
    The world is irradiated every single second of the day for the past what…multi million/billion years, and somehow life developed and flourished – therefore – there can be no such thing as a ZERO threshold.
    End of argument.

    • The simple arguments are often the best.
      At a minimum, the advanced arguments must always answer the simple objections. There are too many people in the world who will argue their way round the houses to prove that 2+2=5.

  17. Age Adjusted cancer incidence rates are higher than before EPA. Unadjusted cancer incidence rates are 50% higher. Cancer incidence among young adults is increasing. Life expectancy is in decline.

    And you all want to weaken standards? The reason it was chosen in the first place is there were no other models to choose from beyond a few underpowered animal studies.

    I don’t mind having a bit of a safe factor.

  18. Why no mention of the Taiwan apartment blocks? I thought the thousands of exposed people represented the best human radiation trail,ever, by accident.

  19. This LNT nonsense has led the EPA to consistently setting drinking water contamination limits to equal the lowest detection limit reasonably attainable.
    For instance, Arsenic had it’s MCL (Maximum Contaminant Level) lowered from 50 ppb to 10ppb (5ppb in New Jersey)

    This despite the fact that consuming an apple or a bowl of rice can easily contain the equivalent Arsenic content of 10 to 100 liters of “unsafe” drinking water. (Under USEPA rules, if a public drinking water supply has 10ppb of Arsenic, it is “unsafe” and the water provider MUST fix the “problem”

    So, here is a link to the facts about eating apples:
    https://www.medicalnewstoday.com/articles/267290.php

    “In fact, apples were ranked first in Medical News Today’s featured article about the top 10 healthy foods.

    Apples are extremely rich in important antioxidants, flavanoids, and dietary fiber.

    The phytonutrients and antioxidants in apples may help reduce the risk of developing cancer, hypertension, diabetes, and heart disease.”

    Yet apples have many times the amount of Arsenic allowed in an equivalent daily average drinking water consumption amount.

    Either 10ppb of Arsenic is “unsafe” or apples are healthy to eat, you can’t have both.

    Of course, there is now an effort to reduce the levels of Arsenic in apples and rice, principally because 10ppb in water is “unsafe”. Circular logic at it’s very worst.

  20. For a good dose of radiation, fly to New York for the weekend, then go to Cornwall and eat a banana.

  21. I think people are too certain on this stuff.

    LNT is just a model, and as such not very useful for realistic politics. It might hold in some cases, but it is very difficult to show, and becomes irrelevant at the zero limit in any case. Scientific papers use language like ‘may cause’, ‘could cause’, or ‘suggests that’. People should remember that this IS just a suggestion, not a fact.

    • However, the LNT usage by the EPA has spawned a vast number of home radon mitigation companies. The EPA, which still uses cPi/l as the measurement, was extrapolated from miners in Pennsylvania who suffered lung cancer. There was no testing done to see what factors actually lead to those lung cancers, they just used radon levels without regard to life style (smokers) and other conditions in the mines.
      The EPA guidelines are not law and pertain to residential properties. However, real estate agents must deal with possible litigation against them if they are not careful in their disclosures about radon and allowing a buyer to have a radon test performed. This is all due to uniformed legislators and lawyers.
      There has never been one case of lung cancer to have been caused by exposure to residential levels of radon in homes. The reality is that the EPA charts for number of people likely to get lung cancer using the LNT extrapolation actually shows that smokers have a much higher rate of lung cancer over non smokers in those residences. Seems like smoking is the real cause of increased lung cancers not radon exposure.

      • Tom in Florida
        I recollect a couple of studies for asbestos and uranium where a significant fraction of the miners were Mormon and didn’t smoke. The rates of lung cancer for the non-smokers was lower than for the smokers.

  22. LNT alarmists cannot explain the paradox of ‘toxic’ vitamins, such as vitamin A and D.

    In addition to hormesis, hopefully also modern scientific methods and metrology will be rediscovered soon.

  23. Taking into consideration ‘risk = exposure x hazard’ based on UN definition, “cancer risk assessment” of the Safe Drinking Water Act in 1974 may still be within reason, but the subsequent LNT conjectures are oxymoronic by definition.

    Even in theoretical world of hazards only, cancer is not an immediate effect of exposure. It can take months if not years to manifest itself. Establishing the causality is far from straight-forward.

    This is the reason why LNT model sounds to me like a CYA precautionary principle by civil servants unwilling to accept any responsibility for establishing safety thresholds in the uncertainty. In any case LNT has gone unchecked, unchallenged, too far and too long.

    If Ravi Batra’s Law of Social Cycle conjecture has any predictive power, the situation will balance itself. Hopefully peacefully.

  24. LNT is the same sort of rationalization that leads to the idea that more CO2=dangerous climate change.
    A rationalization that if ores the data.

  25. LNT was of course a convenient basis on which to regulate, but it was never an effective model of how anything works in the real world.

    Easiest of all examples to comprehend: viral and bacterial infection.

    As we all know from our history teachings, the people living in the Americas had no exposure to several diseases that were common in the “old world”, including small pox. And that as part of the so-called “Colombian Exchange”, the native populations in the Americas were severely impacted by deaths due to exposure to the “old world” diseases, while the European and imported African slaves were not impacted as much. Being exposed to low concentrations of pathogens, especially “dead” pathogens, clearly helps build immunity to infectious diseases.

    Of course, even that bit of history has been greatly exaggerated and overblown, because in many instances the native American populations were not decimated by disease exposure but also because they practiced no means of disease control, such as sanitation, or dealing with sick persons and the dead, and relied (unlike Europeans) on drinking water, while Europeans relied much more on fermented alcohol beverages for moisture intake, so were much less inclined to drink contaminated water. The Europeans may not have understood bacterial and viral infections, and how infectious diseases worked, but by the 16th century and beyond they had devised a variety of means, even if unwittingly, that led to lower mortality rates for “old world” diseases. Europeans also were ravaged by “New World” diseases for which they had no immunity.

    As always, the simplest models for how stuff works are almost always the least accurate models for how stuff works.

  26. This article and comment string put me in mind of Dr. Bruce Ames, made famous by the cancer screening test for chemicals known by his name and, he protested, made infamous by its misuse. He was quite a guy and I saved several of his papers. Here is one that is summary in nature, “Science and the Environment: Facts v. Phantoms”. https://fee.org/articles/science-and-the-environment/

  27. Radiation limits were originally based on a wild best guess. Take the lowest known level of radiation for which acute effects can be detected and divide by 10. But what is not included in any limit or LNT value is individual susceptibility and specific cancer outcomes. Low dose radiation lowers the risk for most cancers but not all. Lukemia is one that may have an increased risk at a lower dose levels but is again highly dependent on the individual. So the real question with LNT is this: Does the lowering of risk for a dozen cancels, as an aribitrary example, outweigh the rising risk for one cancer. In short, it can be a legal nightmare.

  28. Until reading this report I had thought that Brexit might be the most costly face-saving exercise in the history of man. But now I’m wondering whether LNT isn’t more deserving of that dubious distinction.

  29. My fault, prior placed on the following thread when that’s the according thread:

    Due to the low population density, there are hardly any medical centers in north siberian. In addition, the younger population mostly emigrates for education and training to the larger cities. So “medical trains” regularly visit and drive through the region.

    https://www.google.com/search?client=ms-android-huawei&ei=E7InXbekD-2urgTUlIX4DQ&q=siberia%27s+medical+train&oq=Siberian+medicaltrain&gs_l=mobile-gws-wiz-serp.

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