The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 2. How a mistake led BEIR I to adopt LNT

Recent discoveries on the historical foundations of cancer risk assessment: Shedding light on the limits of LNT

Within the past three years there has been a spate of historical discoveries by our research team on various different facets of the historical foundations of cancer risk assessment. This series of discoveries was stimulated by the creation of a 22-episode documentary of the historical foundations of cancer risk assessment by the US Health Physics Society and the need to provide documentation. This process yielded nearly two dozen distinct historical findings which have been published in numerous papers in the peer-reviewed literature. These discoveries are itemized and summarized in the present paper, along with the significance of each discovery within the historical context of ionizing radiation research and cancer risk assessment.

Muller and mutations: mouse study of George Snell (a postdoc of Muller) fails to confirm Muller's fruit fly findings, and Muller fails to cite Snell's findings

In 1931, Hermann J. Muller's postdoctoral student, George D. Snell (Nobel Prize recipient--1980) initiated research to replicate with mice Muller's X-ray-induced mutational findings with fruit flies. Snell failed to induce the two types of mutations of interest, based on fly data (sex-linked lethals/recessive visible mutations) even though the study was well designed, used large doses of X-rays, and was published in Genetics. These findings were never cited by Muller, and the Snell paper (Snell, Genetics 20:545-567, 1935) did not cite the 1927 Muller paper (Muller, Science 66:84, 1927). This situation raises questions concerning how Snell wrote the paper (e.g., ignoring the significance of not providing support for Muller's findings in a mammal). The question may be raised whether professional pressures were placed upon Snell to downplay the significance of his findings, which could have negatively impacted the career of Muller and the LNT theory. While Muller would receive worldwide attention, and receive the Nobel Prize in 1946 "for the discovery that mutations can be induced by X-rays," Snell's negative mutation data were almost entirely ignored by his contemporary and subsequent radiation genetics/mutation researchers. This raises questions concerning how the apparent lack of interest in Snell's negative findings helped Muller professionally, including his success in using his fruit fly data to influence hereditary and cancer risk assessment and to obtain the Nobel Prize.

How Hermann J. Muller Viewed the Ernest Sternglass Contributions to Hereditary and Cancer Risk Assessment

ABSTRACT

As one of the most influential radiation geneticists of the 20th century, Hermann J. Muller had a major role in the development and widespread acceptance of the linear no-threshold (LNT) dose response for hereditary and cancer risk assessments worldwide. However, a spate of historical reassessments have challenged the fundamental scientific foundations of the LNT model, drawing considerable attention to issues of ethical probity and the scientific leadership of Muller. This review paper raises further questions about the objectivity of Muller with respect to the LNT model. It is shown that Muller supported Ernest Sternglass's findings and interpretations concerning radiation-induced childhood leukemia, which have been widely and consistently discredited. These findings provide further evidence that Muller's actions with respect to radiation cancer risk assessment were far more ideologically than scientifically based.

Muller misled the Pugwash Conference on radiation risks

The Pugwash Conferences have been a highly visible attempt to create profoundly important discussions on matters related to global safety and security at the highest levels, starting in 1957 at the height of the Cold War. This paper assesses, for the first time, the formal comments offered at this first Pugwash Conference by the Nobel Prize-winning radiation geneticist, Hermann J. Muller, on the effects of ionizing radiation on the human genome. This analysis shows that the presentation by Muller was highly biased and contained scientific errors and misrepresentations of the scientific record that resulted in seriously misleading the attendees. The presentation of Muller at Pugwash served to promote, on a very visible global scale, continued misrepresentations of the state of the science and had a significant impact on policies and practices internationally and both scientific and personal belief systems concerning the effects of low dose radiation on human health. These misrepresentations would come to affect the adoption and use of nuclear technologies and the science of radiological and chemical carcinogen health risk assessment, ultimately having a profound effect on global environmental health.

Background radiation and cancer risks: A major intellectual confrontation within the domain of radiation genetics with multiple converging biological disciplines

This paper assesses the judgments of leading radiation geneticists and cancer risk assessment scientists from the mid-1950s to mid-1970s that background radiation has a significant effect on human genetic disease and cancer incidence. This assumption was adopted by the National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel for genetic diseases and subsequently applied to cancer risk assessment by other leading individuals/advisory groups (e.g., International Commission on Radiation Protection-ICRP). These recommendations assumed that a sizeable proportion of human mutations originated from background radiation due to cumulative exposure over prolonged reproductive periods and the linear nature of the dose-response. This paper shows that the assumption that background radiation is a significant cause of spontaneous mutation, genetic diseases, and cancer incidence is not supported by experimental and epidemiological findings, and discredits erroneous risk assessments that improperly influenced the recommendations of national and international advisory committees, risk assessment policies, and beliefs worldwide.

How self-interest and deception led to the adoption of the linear non-threshold dose response (LNT) model for cancer risk assessment

This paper clarifies scientific contributions and deceptive/self-serving decisions of William L. Russell and Liane Russell that led to the adoption of the linear non-threshold (LNT) model for cancer risk assessment by the US EPA. By deliberately failing to report an extremely large cluster of mutations in the control group of their first experiment, and thereby greatly suppressing its mutation rate, the Russells incorrectly claimed that the male mouse was 15-fold more susceptible to ionizing-radiation-induced gene mutations as compared with fruit flies. This self-serving error not only propelled their research program into one of great prominence, but it also promoted the LNT-based doubling dose (DD) concept in radiation genetics/cancer risk assessment, by the US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel (1956). The DD concept became a central element in their recommendation that regulatory agencies switch from a threshold to an LNT model. This error occurred because of a decision by W. Russell not to report that a large cluster of control group mutations found in an experiment for which preliminary results were reported in 1951. This failure to report that cluster and similar clusters continued throughout the careers of the Russells, resulting in massive overestimation of low dose radiation risks supporting the LNT. The Russell database and the repeated claim that those data show that there is no threshold dose rate for mutation in irradiated mouse stem-cell spermatogonia, have provided mechanistic validation supporting the epidemiological LNT hypothesis for radiation-induced leukemias and cancers. This reanalysis supports the threshold model for both males and females, thereby rebutting epidemiological extrapolations from the NAS and EPA claiming support for the LNT hypothesis for cancer risk assessment. The implications of the Russell errors/deceptions, how/why they occurred, and their impact upon society are enormous and need to be addressed by scientific/regulatory agencies, affecting regulatory and litigation activities.

Muller mistakes: The linear no-threshold (LNT) dose response and US EPA's cancer risk assessment policies and practices

This paper identifies the occurrence of six major conceptual scientific errors of Hermann Muller and describes how these errors led to the creation of the linear no-threshold (LNT) dose response historically used worldwide for cancer risk assessments for chemical carcinogens and ionizing radiation. The paper demonstrates the significant role that Muller played in the environmental movement, affecting risk assessment policies and practices that are in force even now a half century following his death. This paper lends support to contemporary research that shows significant limitations of the LNT model for cancer risk assessment.

Dose response and risk assessment: Evolutionary foundations

The present paper indicates that the origin of the LNT concept for ionizing radiation was based on insufficient understanding of evolution, which precluded the possibility of repair of gene mutation. The denial of such repair processes had important implications, leading to a belief in a linear dose response and thus in Hermann J Muller's proclamation of a Proportionality Rule for ionizing radiation. The paper documents how the lack of repair concept dominated the radiation geneticist community to the 1960s leading to the establishment of the linear no threshold dose response (LNT) model for radiation and chemical reproductive and cancer risk assessment. Research from the late 1950s onward would establish the occurrence, generality, and efficacy of genetic and cellular repair processes. While the assumption of a lack of gene mutation repair was wrong, Muller was correct that dose-response concepts need to be founded on mechanistic understandings of evolution. Such mechanisms require the integration of constitutive and inducible adaptive and repair mechanisms that operate in the low-dose zone. This perspective reflects the comment of Dobzhansky (1973) that "nothing makes sense in biology except in light of evolution." While this is a powerful scientific dictum, it assumes a correct understanding of evolution, something that the origins of the LNT dose response lacked. Such modern mechanistic repair developments reveal that the historical foundations of LNT were flawed from the start. Nonetheless, they have been carried forward to the present time, principally by environmental health regulatory agencies that decoupled risk assessment policy from a sound evolutionary foundation.

Ethical challenges of the linear non-threshold (LNT) cancer risk assessment revolution: History, insights, and lessons to be learned

This paper provides historical review and evaluation of the development, adoption, and advocacy of the linear non-threshold (LNT) dose response model for cancer risk assessment as applied in practices and policies worldwide. It extends previous historical assessments and provides novel insights regarding: 1) how LNT bias became institutionalized in US governmental agencies, 2) how improper editorial practices at the journal Science promoted the adoption of LNT, 3) how a Nobel Prize winning scientist unjustifiably espoused and influenced support for replacing the threshold dose response model with the LNT model, 4) how the cover-up of striking and substantial experimental cancer data by US government scientists reduced support for the threshold dose response model at a critical period of cancer risk assessment policy adoption, and 5) how these events have negatively influenced cancer risk assessment practices and environmental and public health decisions for decades. These findings are presented to illustrate how profound and recognized mistakes, biases and unethical activities, inclusive of frank scientific misconduct, converged, and should motivate regulatory agencies worldwide to critically evaluate any existing policies that apply the LNT model as well as to serve as object lessons for current and future ethical conduct of research, and the provision of ethico-legal education in and across scientific curricula and institutions.

Cover up and cancer risk assessment: Prominent US scientists suppressed evidence to promote adoption of LNT

This paper reports that William Russell, Oak Ridge National Laboratory (ORNL), conducted a large-scale lifetime study from 1956 to 1959 showing that exposure of young adult male mice to a large dose of acute X-rays had no treatment effects on male and female offspring concerning longevity or the frequency, severity, or age distribution of neoplasms and other diseases. Despite the scientific, societal and crucial timing significance of the study, Russell did not publish the findings for almost 35 years, nor did he inform governmental advisory committees, thereby significantly biasing decisions made during this period which supported the adoption of LNT for risk assessment. Of further significance, Arthur Upton, an ORNL colleague of Russell during this study and later Director of the US National Cancer Institute (NCI), was also fully knowledgeable of this study, its findings and its negative impact on the acceptance of LNT. Upton later worked along with Russell to publish these data (i.e., Cosgrove et al., 1993) to dispute the case-specific claim that children developed cancer because of the radiation exposure of their fathers as workers at the Sellafield nuclear plant. Thus, while Russell's data were available, but were not used to challenge the key radiation and leukemia paper of Edward B. Lewis, (1957) when LNT was being adopted by regulatory agencies, they were used in a major trial in the United Kingdom (UK) for the client (i.e., British Nuclear Fuels Plc) that hired Upton. While the duplicity of Russell's and Upton's actions is striking, the key finding of the present paper is that Russell and Upton intentionally orchestrated and sustained an LNT cover up during the key period of LNT adoption by regulatory agencies, thereby showing an overwhelming bias to enhance the adoption of LNT.

Thresholds for carcinogens

Current regulatory cancer risk assessment principles and practices assume a linear dose-response relationship-the linear no-threshold (LNT) model-that theoretically estimates cancer risks occurring following low doses of carcinogens by linearly extrapolating downward from experimentally determined risks at high doses. The two-year rodent bioassays serve as experimental vehicles to determine the high-dose cancer risks in animals and then to predict, by extrapolation, the number of carcinogen-induced tumors (tumor incidence) that will arise during the lifespans of humans who are exposed to environmental carcinogens at doses typically orders of magnitude below those applied in the rodent assays. An integrated toxicological analysis is conducted herein to reconsider an alternative and once-promising approach, tumor latency, for estimating carcinogen-induced cancer risks at low doses. Tumor latency measures time-to-tumor following exposure to a carcinogen, instead of tumor incidence. Evidence for and against the concept of carcinogen-induced tumor latency is presented, discussed, and then examined with respect to its relationship to dose, dose rates, and the dose-related concepts of initiation, tumor promotion, tumor regression, tumor incidence, and hormesis. Considerable experimental evidence indicates: (1) tumor latency (time-to-tumor) is inversely related to the dose of carcinogens and (2) lower doses of carcinogens display quantifiably discrete latency thresholds below which the promotion and, consequently, the progression and growth of tumors are delayed or prevented during a normal lifespan. Besides reconciling well with the concept of tumor promotion, such latency thresholds also reconcile favorably with the existence of thresholds for tumor incidence, the stochastic processes of tumor initiation, and the compensatory repair mechanisms of hormesis. Most importantly, this analysis and the arguments presented herein provide sound theoretical, experimental, and mechanistic rationales for rethinking the foundational premises of low-dose linearity and updating the current practices of cancer risk assessment to include the concept of carcinogen thresholds.

Ethical failings: The problematic history of cancer risk assessment

This paper demonstrates that unethical conduct by the US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel led to their recommendation of the Linear Non-Threshold (LNT) Model for radiation risk assessment and its subsequent adoption by the US and the world community. The analysis, which is based largely on preserved communications of the US NAS Genetics Panel members, reveals that Panel members and their administrative leadership at the NAS displayed an integrated series of unethical actions designed to ensure, (1) the acceptance of the LNT and (2) funding to radiation geneticist panel members and professional colleagues. These findings are significant because major public policies in open democracies, such as cancer risk assessment and other issues impacted by public fears of radiation or chemical exposures, require ethical foundations. Recognition of these ethical failures of the BEAR I Genetics Panel should require a high level administrative, legislative and scientific reassessment of the scientific foundations of cancer risk assessment, with the likely result necessitating revision of current policies and practices. The BEAR I Genetics Panel, 1956 Science journal publication should immediately be retracted because it contains deliberate misrepresentations of the scientific record that were designed to manipulate scientific and public opinion on radiation risk assessment in a dishonest manner.

The Muller-Neel dispute and the fate of cancer risk assessment

The National Academy of Sciences (NAS) Atomic Bomb Casualty Commission (ABCC) human genetic study (i.e., The Neel and Schull, 1956a report) showed an absence of genetic damage in offspring of atomic bomb survivors in support of a threshold model, but was not considered for evaluation by the NAS Biological Effects of Atomic Radiation (BEAR) I Genetics Panel. The study therefore could not impact the Panel's decision to recommend the linear non-threshold (LNT) dose-response model for risk assessment. Summaries and transcripts of the Panel meetings failed to reveal an evaluation of this study, despite its human relevance and ready availability, relying instead on data from Drosophila and mice. This paper explores correspondence among and between BEAR Genetics Panel members, including James Néel, the study director, and other contemporaries to assess why the Panel failed to use these data and how the decision to recommend the LNT model affected future cancer risk assessment policies and practices. This failure of the Genetics Panel was due to: (1) a strongly unified belief in the LNT model among panel members and their refusal to acknowledge that a low dose of radiation could exhibit a threshold, a conclusion that the Néel/Schull atomicbomb study could support, and (2) an excessive degree of self-interest among panel members who experimented with animal models, such as Hermann J. Muller, and feared that human genetic studies would expose the limitations of extrapolating from animal (especially Drosophila) to human responses and would strongly shift research investments/academic grants from animal to human studies. Thus, the failure to consider the Néel/Schull atomic bomb study served both the purposes of preserving the LNT policy goal and ensuring the continued dominance of Muller and his similarly research-oriented colleagues.

The downfall of the linear non-threshold model

The linear non-threshold model (LNTM) is a theoretical dose-response function as a result of extrapolating the late effects of high-dose exposure to ionizing radiation to the low-dose range, but there is great uncertainty about its validity. The acceptance of LNTM as the dominant probabilistic model have survived to the present day and it is actually the cornerstone of current radiation protection policies. In the last decades, advances in molecular and evolutive biology, cancer immunology, and many epidemiological and animal studies have cast serious doubts about the reliability of the NLTM, as well as suggesting alternative models, like the hormetic theory. Considering the given evidences, a discussion between the involved scientific societies and the regulatory commissions is promtly required in order to to reach a redefiniton of theradiation protection basis, as it would be specially crucial in the medical field.

X-Ray Hesitancy: Patients' Radiophobic Concerns Over Medical X-rays

All too often the family physician, orthopedic surgeon, dentist or chiropractor is met with radiophobic concerns about X-ray imaging in the clinical setting. These concerns, however, are unwarranted fears based on common but ill-informed and perpetuated ideology versus current understanding of the effects of low-dose radiation exposures. Themes of X-ray hesitancy come in 3 forms: 1. All radiation exposures are harmful (i.e. carcinogenic); 2. Radiation exposures are cumulative; 3. Children are more susceptible to radiation. Herein we address these concerns and find that low-dose radiation activates the body's adaptive responses and leads to reduced cancers. Low-dose radiation is not cumulative as long as enough time (e.g. 24 hrs) passes prior to a repeated exposure, and any damage is repaired, removed, or eliminated. Children have more active immune systems; the literature shows children are no more affected than adults by radiation exposures. Medical X-rays present a small, insignificant addition to background radiation exposure that is not likely to cause harm. Doctors and patients alike should be better informed of the lack of risks from diagnostic radiation and the decision to image should rely on the best evidence, unique needs of the patient, and the expertise of the physician-not radiophobia.

Theodosius Dobzhansky's view on biology and evolution v.2.0: "Nothing in biology makes sense except in light of evolution and evolution's dependence on hormesis-mediated acquired resilience that optimizes biological performance and numerous diverse short and longer term protective strategies"

The hormetic, biphasic dose response, is highly generalizable, being independent of biological model, level of biological organization, endpoint, inducing agent, and mechanisms. It plays a significant role in mediating both constitutive and adaptable responses in essentially all cells and organisms. The present paper provides both a historical overview of the origin of the hormetic concept in the biological and biomedical sciences, and its potential role in ecology, evolution, and development. These integrative findings provide a broad scientific framework to better understand complex evolutionary-based selection strategies, affecting survival, lifespan, fecundity, learning/memory, tissue repair, reproduction and cooperation, and developmental processes, and offering resilience in the presence of numerous challenges.

The Selby-Russell Dispute Regarding the Nonreporting of Critical Data in the Mega-Mouse Experiments of Drs William and Liane Russell That Spanned Many Decades: What Happened, Current Status, and Some Ramifications

The Russells began their studies of the hereditary effects of radiation in the late 1940s, and their experiments contributed much to what is known about the induction of gene mutations in mice. I had a close association with them for about 26 years, and they relied on me considerably for database management and statistical support. In 1994, I was shocked to discover that, in experiments on males, they had failed to report numerous spontaneous mutations that arose during the perigametic interval and were detected as clusters of mutations. I realized that their nondisclosure of this information meant that the decades-long application of their data to estimate hereditary risks of radiation to humans using the doubling-dose approach had resulted in a several-fold overestimation of risk. I accordingly reported the situation to funding agencies. The resulting complicated situation is referred to here as the Selby-Russell Dispute. Highlights of the resulting investigation, as well as what occurred afterward, are described, and reasons will be provided to show why, in my opinion, the hereditary risk from radiation in humans was likely overestimated by at least 10-fold because the Russells decided not to report critical information from their massive experiments.

Towards a New Concept of Low Dose

When people discuss the risks associated with low doses of ionizing radiation, central to the discussion is the definition of a low dose and the nature of harm. Standard answers such as "doses below 0.1 Gy are low" or "cancer is the most sensitive measure of harm" obscure the complexity within these seemingly simple questions. This paper will discuss some of the complex issues involved in determining risks to human and nonhuman species from low-dose exposures. Central to this discussion will be the role of communicable responses to all stressors (often referred to as bystander responses), which include recently discovered epigenetic and nontargeted mechanisms. There is a growing consensus that low-dose exposure to radiation is but one of many stressors to impact populations. Many of these stressors trigger responses that are generic and not unique to radiation. The lack of a unique radiation signature makes absolute definition of radiation risk difficult. This paper examines a possible new way of defining low dose based on the systemic response to the radiation. Many factors will influence this systemic response and, because it is inherently variable, it is difficult to predict and so makes low-dose responses very uncertain. Rather than seeking to reduce uncertainty, it might be valuable to accept the variability in outcomes, which arise from the complexity and multifactorial nature of responses to stressors.

Reforming the debate around radiation risk

The back-and-forth debate on radiation risk, in the recent years, has unscientifically drifted away from proportionality and become increasingly antagonistic. A handful of authors have used exaggerated claims which are corroborated by their own previous work and presented using heated and superlative language. With unwarranted certainty, many have also referenced studies which report inconclusive findings and given undue weight to the results of laboratory animal and cellular studies, regardless of their exact positions on radiation risk. The passion and subjective interpretation with which the debate is now presented detracts from rational, scientific evaluation. A reform of the debate is needed to reach grounded consensus in the community and, if appropriate, begin the process of amending the legislation to reflect it. In this article we have analysed key research on the topic and discussed the fundamental limitations of science in providing satisfactory answers to our questions.

The linear No-Threshold (LNT) dose response model: A comprehensive assessment of its historical and scientific foundations

The linear no-threshold (LNT) single-hit (SH) dose response model for cancer risk assessment is comprehensively assessed with respect to its historical foundations. This paper also examines how mistakes, ideological biases, and scientific misconduct by key scientists affected the acceptance, validity, and applications of the LNT model for cancer risk assessment. In addition, the analysis demonstrates that the LNT single-hit model was inappropriately adopted for governmental risk assessment, regulatory policy, practices, and for risk communication.

Risk of Radiation-Induced Cancer From Computed Tomography Angiography Use in Imaging Surveillance for Unruptured Cerebral Aneurysms

Background and Purpose- Although computed tomography angiography (CTA) is an excellent, noninvasive imaging modality for surveillance of intracranial aneurysms, radiation concerns have been cited to restrict its use in surveillance imaging. The goal of this study was to estimate distributions of radiation-induced central nervous system cancer incidence from CTA surveillance for intracranial aneurysms, and the impact of frequency and duration of surveillance imaging using follow-up CTAs. Methods- Simulation-modeling approach was performed using data on CTA associated radiation risk. We used the Radiation Risk Assessment Tool, based on the data using the BEIR VII report (BEIR VII). Each CTA was assigned as a separate exposure event. Men and women, respectively, starting surveillance imaging at 30, 40, and 50 years and receiving annual CTAs were considered as separate subgroups. As a comparison, we also calculated the radiation-induced cancer risk in the same groups of patients but receiving CTAs every 2 and 5 years, respectively. Results- CTA-associated excess cancer risk per exposure increases relatively more rapidly with the first 10 exposures and plateaus after the 44th exposure. On average, per CTA incurs ≈0.0026% in excess lifetime cancer risk. Receiving CTA follow-up at a younger age, more frequent follow-up, longer surveillance period, and men are the major factors contributing to an elevated excess lifetime risk. In the highest risk group, male patient receiving annual CTA follow-ups from the age of 30 years, the excess lifetime risk is 0.115% at the age of 81 years. Conclusions- Radiation-induced brain cancer incidence associated with unruptured intracranial aneurysm surveillance strategies using CTA is low relative to the risk for aneurysmal rupture. Further cost-effectiveness/utility analyses might help assess this risk in the context of aneurysmal ruptures prevented by surveillance imaging.

A critical evaluation of the NCRP COMMENTARY 27 endorsement of the linear no-threshold model of radiation effects

Regulatory policy to protect the public and the environment from radiation is universally based on the linear, no-threshold model (LNT) of radiation effects. This model has been controversial since its inception over nine decades ago, and remains so to this day, but it has proved remarkably resistant to challenge from the scientific community. The LNT model has been repeatedly endorsed by expert advisory bodies, and regulatory agencies in turn adopt policies that reflect this advice. Unfortunately, these endorsements rest on a foundation of institutional inertia and numerous logical fallacies. These include most significantly setting the LNT as the null hypothesis, and shifting the burden of proof onto LNT skeptics. Other examples include arbitrary exclusion of alternative hypotheses, ignoring criticisms of the LNT, cherry-picking evidence, and making policy judgements without foundation. This paper presents an evaluation of the National Council on Radiation Protection and Measurements' (NCRP) Commentary 27, which concluded that recent epidemiological studies are compatible with the continued use of the LNT model for radiation protection. While this report will likely provide political cover for regulators' continued reliance on the LNT, it is a missed opportunity to advance the scientific discussion of the effects of low dose, low dose-rate radiation exposure. Due to its Congressionally chartered mission, no organization is better positioned than the NCRP to move this debate forward, and recommendations for doing so in future reviews are provided.

Muller's nobel prize research and peer review

BACKGROUND

This paper assesses possible reasons why Hermann J. Muller avoided peer-review of data that became the basis of his Nobel Prize award for producing gene mutations in male Drosophila by X-rays.

METHODS

Extensive correspondence between Muller and close associates and other materials were obtained from preserved papers to compliment extensive publications by and about Muller in the open literature. These were evaluated for potential historical insights that clarify why he avoided peer-review of his Nobel Prize findings.

RESULTS

This paper clarifies the basis of Muller's (Muller HJ, Sci 66 84-87, 1927c) belief that he produced X-ray induced "gene" mutations in Drosophila. It then shows his belief was contemporaneously challenged by his longtime friend/confidant and Drosophila geneticist, Edgar Altenburg. Altenburg insisted that Muller may have simply poked large holes in chromosomes with massive doses of X-rays, and needed to provide proof of gene "point" mutations. Given the daunting and uncertain task to experimentally address this criticism, especially within the context of trying to become first to produce gene mutations, it is proposed that Muller purposely avoided peer-review while rushing to publish his paper in Science to claim discovery primacy without showing any data. The present paper also explores ethical issues surrounding these actions, including those of the editor of Science, James McKeen Catell and Altenburg, and their subsequent impact on the scientific and regulatory communities.

CONCLUSION

This historical analysis suggests that Muller deliberately avoided peer-review on his most significant findings because he was extremely troubled by the insightful and serious criticism of Altenburg, which suggested he had not produced gene mutations as he claimed. Nonetheless, Muller manipulated this situation (i.e., publishing a discussion within Science with no data, publishing a poorly written non-peer reviewed conference proceedings with no methods and materials, and no references) due to both the widespread euphoria over his claim of gene mutation and confidence that Altenburg would not publically challenge him. This situation permitted Muller to achieve his goal to be the first to produce gene mutations while buying him time to later try to experimentally address Altenburg's criticisms, and a possible way to avoid discovery of his questionable actions.

Hormesis: Path and Progression to Significance

This paper tells the story of how hormesis became recognized as a fundamental concept in biology, affecting toxicology, microbiology, medicine, public health, agriculture, and all areas related to enhancing biological performance. This paper assesses how hormesis enhances resilience to normal aging and protects against a broad spectrum of neurodegenerative, cardiovascular, and other diseases, as well as trauma and other threats to health and well-being. This paper also explains the application of hormesis to several neurodegenerative diseases such as Parkinson’s and Huntington’s disease, macrophage polarization and its systematic adaptive protections, and the role of hormesis in enhancing stem cell functioning and medical applications.

Emission of volatile organic compounds from plants shows a biphasic pattern within an hormetic context

Biogenic volatile organic compounds (BVOCs) are released to the atmosphere from vegetation. BVOCs aid in maintaining ecosystem sustainability via a series of functions, however, VOCs can alter tropospheric photochemistry and negatively affect biological organisms at high concentrations. Due to their critical role in ecosystem and environmental sustainability, BVOCs receive particular attention by global change biologists. To understand how plant VOC emissions affect stress responses within a dose-response context, dose responses should be evaluated. This commentary collectively documents hormetic-like responses of plant-emitted VOCs to external stimuli. Hormesis is a generalizable biphasic dose response phenomenon where the response to low doses acts in an opposite way at high doses. These collective findings suggest that ecological implications of low-level stress that may alter BVOC emissions should be considered in future studies. This commentary promotes new insights into the interface between biological systems and environmental change that influence several parts of the globe, and provide a base for advancing hazard assessment testing strategies and protocols to provide decision makers with adequate data for generating environmental standards.

It Is Time to Move Beyond the Linear No-Threshold Theory for Low-Dose Radiation Protection

The US Environmental Protection Agency (USEPA) is the primary federal agency responsible for promulgating regulations and policies to protect people and the environment from ionizing radiation. Currently, the USEPA uses the linear no-threshold (LNT) model to estimate cancer risks and determine cleanup levels in radiologically contaminated environments. The LNT model implies that there is no safe dose of ionizing radiation; however, adverse effects from low dose, low-dose rate (LDDR) exposures are not detectable. This article (1) provides the scientific basis for discontinuing use of the LNT model in LDDR radiation environments, (2) shows that there is no scientific consensus for using the LNT model, (3) identifies USEPA reliance on outdated scientific information, and (4) identifies regulatory reliance on incomplete evaluations of recent data contradicting the LNT. It is the time to reconsider the use of the LNT model in LDDR radiation environments. Incorporating the latest science into the regulatory process for risk assessment will (1) ensure science remains the foundation for decision making, (2) reduce unnecessary burdens of costly cleanups, (3) educate the public on the real effects of LDDR radiation exposures, and (4) harmonize government policies with the rest of the radiation scientific community.

The EPA Cancer Risk Assessment Default Model Proposal: Moving Away From the LNT

This article strongly supports the Environmental Protection Agency proposal to make significant changes in their cancer risk assessment principles and practices by moving away from the use of the linear nonthreshold (LNT) dose-response as the default model. An alternate approach is proposed based on model uncertainty which integrates the most scientifically supportable features of the threshold, hormesis, and LNT models to identify the doses that optimize population-based responses (ie, maximize health benefits/minimize health harm). This novel approach for cancer risk assessment represents a significant improvement to the current LNT default method from scientific and public health perspectives.

Was Muller's 1946 Nobel Prize research for radiation-induced gene mutations peer-reviewed?

This historical analysis indicates that it is highly unlikely that the Nobel Prize winning research of Hermann J. Muller was peer-reviewed. The published paper of Muller lacked a research methods section, cited no references, and failed to acknowledge and discuss the work of Gager and Blakeslee (PNAS 13:75-79, 1927) that claimed to have induced gene mutation via ionizing radiation six months prior to Muller's non-data Science paper (Muller, Science 66(1699):84-87, 1927a). Despite being well acclimated into the scientific world of peer-review, Muller choose to avoid the peer-review process on his most significant publication. It appears that Muller's actions were strongly influenced by his desire to claim primacy for the discovery of gene mutation. The actions of Muller have important ethical lessons and implications today, when self-interest trumps one's obligations to society and the scientific culture that supports the quest for new knowledge and discovery.

Elemental mercury neurotoxicity and clinical recovery of function: A review of findings, and implications for occupational health

This paper assessed approximately 30 studies, mostly involving occupationally exposed subjects, concerning the extent to which those who developed elemental mercury (Hg)-induced central and/or peripheral neurotoxicities from chronic or acute exposures recover functionality and/or performance. While some recovery occurred in the vast majority of cases, the extent of such recoveries varied considerably by individual and endpoint. Factors accounting for the extensive inter-individual variation in toxicity and recovery were not specifically assessed such as age, gender, diet, environmental enrichment, chelation strategies and dose-rate. While the data indicate that psychomotor endpoints often show substantial and relatively rapid (i.e., 2-6 months) recovery and that neuropsychological endpoints display slower and less complete recovery, generalizations are difficult due to highly variable study designs, use of different endpoints measured between studies, different Hg exposures based on blood/urine concentrations and Hg dose-rates, the poor capacity for replicating findings due to the unpredictable/episodic nature of harmful exposures to elemental Hg, and the inconsistency of the initiation of studies after induced toxicities and the differing periods of follow up during recovery periods. Finally, there is strikingly limited animal model literature on the topic of recovery/reversibility of elemental Hg toxicity, a factor which significantly contributes to the overall marked uncertainties for predicting the rate and magnitude of recovery and the factors that affect it.

Radiophobia: 7 Reasons Why Radiography Used in Spine and Posture Rehabilitation Should Not Be Feared or Avoided

Evidence-based contemporary spinal rehabilitation often requires radiography. Use of radiography (X-rays or computed tomography scans) should not be feared, avoided, or have their exposures lessened to decrease patient dose possibly jeopardizing image quality. This is because all fears of radiation exposures from medical diagnostic imaging are based on complete fabrication of health risks based on an outdated, invalid linear model that has simply been propagated for decades. We present 7 main arguments for continued use of radiography for routine use in spinal rehabilitation: (1) the linear no-threshold model for radiation risk estimates is invalid for low-dose exposures; (2) low-dose radiation enhances health via the body's adaptive response mechanisms (ie, radiation hormesis); (3) an X-ray with low-dose radiation only induces 1 one-millionth the amount of cellular damage as compared to breathing air for a day; (4) radiography is below inescapable natural annual background radiation levels; (5) radiophobia stems from unwarranted fears and false beliefs; (6) radiography use leads to better patient outcomes; (7) the risk to benefit ratio is always beneficial for routine radiography. Radiography is a safe imaging method for routine use in patient assessment, screening, diagnosis, and biomechanical analysis and for monitoring treatment progress in daily clinical practice.

The Mistaken Birth and Adoption of LNT: An Abridged Version

The historical foundations of cancer risk assessment were based on the discovery of X-ray-induced gene mutations by Hermann J. Muller, its transformation into the linear nonthreshold (LNT) single-hit theory, the recommendation of the model by the US National Academy of Sciences, Biological Effects of Atomic Radiation I, Genetics Panel in 1956, and subsequent widespread adoption by regulatory agencies worldwide. This article summarizes substantial recent historical revelations of this history, which profoundly challenge the standard and widely acceptable history of cancer risk assessment, showing multiple significant scientific errors and incorrect interpretations, mixed with deliberate misrepresentation of the scientific record by leading ideologically motivated radiation geneticists. These novel historical findings demonstrate that the scientific foundations of the LNT single-hit model were seriously flawed and should not have been adopted for cancer risk assessment.

Flaws in the LNT single-hit model for cancer risk: An historical assessment

The LNT single-hit model was derived from the Nobel Prize-winning research of Herman J. Muller who showed that x-rays could induce gene mutations in Drosophila and that the dose response for these so-called mutational events was linear. Lewis J. Stadler, another well-known and respected geneticist at the time, strongly disagreed with and challenged Muller's claims. Detailed evaluations by Stadler over a prolonged series of investigations revealed that Muller's experiments had induced gross heritable chromosomal damage instead of specific gene mutations as had been claimed by Muller at his Nobel Lecture. These X-ray-induced alterations became progressively more frequent and were of larger magnitude (more destructive) with increasing doses. Thus, Muller's claim of having induced discrete gene mutations represented a substantial speculative overreach and was, in fact, without proof. The post hoc arguments of Muller to support his gene mutation hypothesis were significantly challenged and weakened by a series of new findings in the areas of cytogenetics, reverse mutation, adaptive and repair processes, and modern molecular methods for estimating induced genetic damage. These findings represented critical and substantial limitations to Muller's hypothesis of X-ray-induced gene mutations. Furthermore, they challenged the scientific foundations used in support of the LNT single-hit model by severing the logical nexus between Muller's data on radiation-induced inheritable alterations and the LNT single-hit model. These findings exposed fundamental scientific flaws that undermined not only the seminal recommendation of the 1956 BEAR I Genetics Panel to adopt the LNT single-hit Model for risk assessment but also any rationale for its continued use in the present day.

Complex DNA Damage: A Route to Radiation-Induced Genomic Instability and Carcinogenesis

Cellular effects of ionizing radiation (IR) are of great variety and level, but they are mainly damaging since radiation can perturb all important components of the cell, from the membrane to the nucleus, due to alteration of different biological molecules ranging from lipids to proteins or DNA. Regarding DNA damage, which is the main focus of this review, as well as its repair, all current knowledge indicates that IR-induced DNA damage is always more complex than the corresponding endogenous damage resulting from endogenous oxidative stress. Specifically, it is expected that IR will create clusters of damage comprised of a diversity of DNA lesions like double strand breaks (DSBs), single strand breaks (SSBs) and base lesions within a short DNA region of up to 15–20 bp. Recent data from our groups and others support two main notions, that these damaged clusters are: (1) repair resistant, increasing genomic instability (GI) and malignant transformation and (2) can be considered as persistent “danger” signals promoting chronic inflammation and immune response, causing detrimental effects to the organism (like radiation toxicity). Last but not least, the paradigm shift for the role of radiation-induced systemic effects is also incorporated in this picture of IR-effects and consequences of complex DNA damage induction and its erroneous repair.

Obituary notice: LNT dead at 89 years, a life in the spotlight

Considerable recent findings have revealed that the linear dose response for cancer risk assessment has not only outlived its utility in predicting risk but is based on a flawed scientific foundation. The present article characterizes this demise of a key concept of environmental risk assessment, in the framework of a figurative obituary of a long-lived concept that has poorly served society. This obituary is intended to illustrate an integrated mix of poignant and improper historical judgments that led to both the acceptance and ultimately the demise of this once intellectually facile and nearly universally accepted concept.

The threshold vs LNT showdown: Dose rate findings exposed flaws in the LNT model part 1. The Russell-Muller debate

This paper assesses the discovery of the dose-rate effect in radiation genetics and how it challenged fundamental tenets of the linear non-threshold (LNT) dose response model, including the assumptions that all mutational damage is cumulative and irreversible and that the dose-response is linear at low doses. Newly uncovered historical information also describes how a key 1964 report by the International Commission for Radiological Protection (ICRP) addressed the effects of dose rate in the assessment of genetic risk. This unique story involves assessments by two leading radiation geneticists, Hermann J. Muller and William L. Russell, who independently argued that the report's Genetic Summary Section on dose rate was incorrect while simultaneously offering vastly different views as to what the report's summary should have contained. This paper reveals occurrences of scientific disagreements, how conflicts were resolved, which view(s) prevailed and why. During this process the Nobel Laureate, Muller, provided incorrect information to the ICRP in what appears to have been an attempt to manipulate the decision-making process and to prevent the dose-rate concept from being adopted into risk assessment practices.