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

Overt Scientific Bias and Clandestine Acts by Trusted Scientists: The Flawed Application of the Linear No-threshold Model

ABSTRACT

The Health Physics Society (HPS) released a video documentary on the history of the linear no-threshold (LNT) model in April 2022. It exposed many scientific and ethical failings of many leaders, influential scientists, and organizations that have resulted in the current system of radiological protection. Since then, the society received many comments; most were supportive, while a few criticized the video documentary as delivering an anti-LNT message. Shortly thereafter, many emails discovered via an independent Freedom of Information Act request revealed multiple layers of coordination between prominent people in the field of radiation protection to coopt the leadership within the HPS and suppress information they perceived or assumed to be contrary to a pro-LNT message. Many of these emails were published by JunkScience.com, an independent organization that exposes faulty scientific data and analyses used to advance special interests and hidden agendas. This Forum article is intended to document in the peer-reviewed literature the JunkScience.com findings of clandestine acts by trusted scientists within the radiation protection community. The emails exposed strong personal biases, actions taken by leaders within the National Commission on Radiation Protection and Measurements (NCRP) to "save the Society" from its "downward spiral," and actions taken by NCRP and HPS members serving on a National Academies of Sciences committee to suppress scientific information relevant to the debate about health effects in low-dose environments. These anti-science actions harm our entire profession and the trust that Congress bestows on our scientific organizations expecting to receive objective recommendations based on sound science. It is important that these events are recorded in the scientific literature from a historical perspective. The radiation protection community will be judged not by what is revealed in this article but by what actions are taken from here.

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.

Muller's genetic load/species extinction hypothesis

The genetic load hypothesis of Hermann Muller raised the profound question of possible species extinction, even for humans, following a prolonged accumulation of recessive genes due to ionizing radiation exposure within the population. Two major mouse radiation research teams in the United States provided the most extensive tests of Muller's hypothesis. One group continued its study for more than two decades, over 82 consecutive generations, approximating 2500 human years. Even though Muller had stressed for decades his fear of species-threatening effects, no significant effects were observed for related factors such as reproductive fitness and longevity. Yet, the paper presenting the data of the 82-generation negative study has only been cited five times in 45 years. Altogether numerous laboratories worldwide collected vast amounts of data on mice, rats, and swine in an unsuccessful attempt to see if there was convincing evidence to support the genetic load theory and claims that species might deteriorate or be rendered extinct. This paper re-examines Muller's genetic load hypothesis with a new evaluation of how that hypothesis was tested and the significance of the findings, with most of those studies being completed before the BEIR I Committee Report in 1972. That committee briefly discussed the available evidence, mostly ignoring those results as they proceeded to make hereditary risk estimates both for (1) the first generation after a radiation exposure and (2) for the time, in the distant future, when a hypothetical genetic equilibrium would be reached. Their estimates assumed accumulation of harmful mutations and a linear no-threshold dose response extending all of the way down to a single ionization. More recent data on induction by ionizing radiation of dominant mutations that affect the skeletons of mice provide further robust supporting evidence that the generationally cumulative and LNT-based assumptions underpinning Muller's genetic load hypothesis are not correct.

Comet assay and hormesis

The paper provides the first assessment of the occurrence of hormetic dose responses using the Comet assay, a genotoxic assay. Using a priori evaluative criteria based on the Hormetic Database on peer-reviewed comet assay experimental findings, numerous examples of hormetic dose responses were obtained. These responses occurred in a large and diverse range of cell types and for agents from a broad range of chemical classes. Limited attempts were made to estimate the frequency of hormesis within comet assay experimental studies using a priori entry and evaluative criteria, with results suggesting a frequency in the 40% range. These findings are important as they show that a wide range of genotoxic chemicals display evidence that is strongly suggestive of hormetic dose responses. These findings have significant implications for study design issues, including the number of doses selected, dose range and spacing. Likewise, the widespread occurrence of hormetic dose responses in this genotoxic assay has important risk assessment implications.

Core self-evaluation and innovative behavior: mediating effect of error orientation and self-efficacy of nurses

Background

Innovation plays a crucial role in advancing nursing and healthcare. Despite its significance, there is a paucity of research examining the interplay among nursing innovative behavior, core self-evaluation, error orientation, and self-efficacy. This study, grounded in Bandura's social cognitive theory, seeks to not only investigate the influence of core self-evaluation on nurses' innovative behavior but also to elucidate the mediating roles of error orientation and self-efficacy within this relationship. By addressing these dynamics, the research aims to provide a comprehensive understanding of the factors shaping nurses' innovative behaviors and contribute to the broader discourse on enhancing healthcare practices.

Design

A cross-sectional study using an online questionnaire.

Setting

Participants were recruited from 23 hospitals in 6 provinces and 1 municipality directly under the central government in China, namely Zhejiang, Anhui, Jiangxi, Guangdong, Hebei, Henan, and Shanghai.

Participants

A total of 741 nurses enrolled in the study.

Methods

The participants completed the nurse innovative behavior scale, the core self-evaluation scale, the error orientation questionnaire, and the self-efficacy scale online in 2023. SPSS and AMOS were used for data analysis. The reporting followed the STROBE checklist.

Results

A total of 706 valid questionnaires were collected. A positive core self-evaluation was associated with more innovative behavior, and this relation was partially mediated by error orientation and self-efficacy to avoid failure. Core self-evaluation, error orientation and self-efficacy of nurses had a positive predictive effect on innovation behavior, with the path coefficients at 0.09, 0.23, and 0.39, respectively.

Conclusion

Our study complements the evidence on the mechanism of action between the core self-evaluation and innovative behavior. Our findings have important clinical implications for promoting innovative behavior in nurses.

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.

Confirmation that Hermann Muller was dishonest in his Nobel Prize Lecture

In his Nobel Prize Lecture of December 12, 1946, Hermann J. Muller argued that the dose-response for ionizing radiation-induced germ cell mutations was linear and that there was ''no escape from the conclusion that there is no threshold''. However, a newly discovered commentary by the Robert L. Brent (2015) indicated that Curt Stern, after reading a draft of part of Muller's Nobel Prize Lecture, called Muller, strongly advising him to remove reference to the flawed linear non-threshold (LNT)-supportive Ray-Chaudhuri findings and strongly encouraged him to be guided by the threshold supportive data of Ernst Caspari. Brent indicated that Stern recounted this experience during a genetics class at the University of Rochester. Brent wrote that Muller refused to follow Stern's advice, thereby proclaiming support for the LNT dose-response while withholding evidence that was contrary during his Nobel Prize Lecture. This finding is of historical importance since Muller's Nobel Prize Lecture gained considerable international attention and was a turning point in the acceptance of the linearity model for radiation and chemical hereditary and carcinogen risk assessment.

The scientific basis for the use of the linear no-threshold (LNT) model at low doses and dose rates in radiological protection

The linear no-threshold (LNT) model was introduced into the radiological protection system about 60 years ago, but this model and its use in radiation protection are still debated today. This article presents an overview of results on effects of exposure to low linear-energy-transfer radiation in radiobiology and epidemiology accumulated over the last decade and discusses their impact on the use of the LNT model in the assessment of radiation-related cancer risks at low doses. The knowledge acquired over the past 10 years, both in radiobiology and epidemiology, has reinforced scientific knowledge about cancer risks at low doses. In radiobiology, although certain mechanisms do not support linearity, the early stages of carcinogenesis comprised of mutational events, which are assumed to play a key role in carcinogenesis, show linear responses to doses from as low as 10 mGy. The impact of non-mutational mechanisms on the risk of radiation-related cancer at low doses is currently difficult to assess. In epidemiology, the results show excess cancer risks at dose levels of 100 mGy or less. While some recent results indicate non-linear dose relationships for some cancers, overall, the LNT model does not substantially overestimate the risks at low doses. Recent results, in radiobiology or in epidemiology, suggest that a dose threshold, if any, could not be greater than a few tens of mGy. The scientific knowledge currently available does not contradict the use of the LNT model for the assessment of radiation-related cancer risks within the radiological protection system, and no other dose-risk relationship seems more appropriate for radiological protection purposes.

Manhattan Project genetic studies: Flawed research discredits LNT recommendations

This paper reexamines the technical report (∼ one page) of Uphoff and Stern (1949) in Science that was highly relied upon by the US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel to support a linearity dose response for radiation risk assessment. The present paper demonstrates that research of Uphoff and Stern (1949) to evaluate whether total dose or dose rate best estimated radiation risks included two variables, thereby precluding the ability to accurately derive a reliable conclusion about this topic. Furthermore, the acute dose selected by Uphoff and Stern was given at a strikingly low dose rate that may have precluded the capacity to adequately test the total dose/dose rate hypothesis, even with a proper study design which also this research did not possess. The issue of total dose and dose rate was much later successfully addressed by Russell et al. (1958) using a murine model, yielding a dose-rate rather than a total dose conclusion. The failure to subject the experimental details of the Uphoff and Stern (1949) study to peer-review and publication in the open literature precluded a rigorous and necessary evaluation, profoundly and improperly impacting the adoption of the linear dose response model.

Ethical Issues in the US 1956 National Academy of Sciences BEAR I Genetics Panel Report to the Public

ABSTRACT

This paper presents newly discovered evidence from the personal correspondence of four US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) Genetics Panelists that their 1956 report to the public was written by a third party and was neither reviewed nor approved by the Panel prior to its publication and release to the public. The letters revealed that the 1956 Report contained serious errors and did not represent the views of the Panel. The failure of the US NAS to notify the public that the Report had not been reviewed and approved by the Panel represents a serious breach of ethics. Further ethical issues relate to the failure of the NAS to (1) correct the errors in the Report within an appropriately timely manner and (2) reveal the lack of approval by the Panel even after the Report's release. In light of these discoveries and the profound historical-and continuing-significance of the 1956 Report to all conventional cancer-related risk assessment processes, we opine that this ethical improbity must be acknowledged and that this document must be retracted by the NAS.