Why Low-level Radiation Exposure Should Not Be Feared.

The purpose of this paper is to address the public fear that is usually associated with low-level radiation exposure situations. Its ultimate objective is to provide persuasive assurances to informed but skeptical members of the public that exposure situations involving low-level radiation are not to be feared. Unfortunately, just acquiescing to an unsupportive public fear of low-level radiation is not without consequences.

The Double Threshold: Consequences for Identifying Low-Dose Radiation Effects.

Prior to observing low-dose-induced cell signaling and adaptive protection, radiogenic stochastic effects were assumed to be linearly related to absorbed dose. Now, abundant data prove the occurrence of radiogenic adaptive protection specifically at doses below ∼ 200 mGy (with some data suggesting such protection at a dose even higher than 200 mGy). Moreover, cells do not thrive properly when deprived of radiation below background dose.

Evidence of a Dose-Rate Threshold for Life Span Reduction of Dogs Exposed Lifelong to γ-Radiation.

Our return to a study on dogs exposed lifelong to cobalt-60 γ-radiation was prompted by a comment that data in dog studies have large statistical errors due to the small number of dogs. We located an earlier article on the same study that had a better mortality curve for the dogs in each dose-rate group. The median life span of the dogs in each group was tabulated, and the standard error of each was calculated.

Biological Effects From Low Doses and Dose Rates of Ionizing Radiation: Science in the Service of Protecting Humans, a Synopsis.

There is considerable controversy regarding risk of health detriment after low-level exposure to ionizing radiation. This stems in part from a sort of distance between radiation biologists, epidemiologists, and radiation protection professionals, as well as regulatory institutions. Also, there is a lack of overview of the relevant data and their origins regarding health risks at low doses of ionizing radiation.

Radiation Hormesis: The Link to Nanomolar Hydrogen Peroxide.

Hydrogen peroxide (HO) is a stable product of water radiolysis, occurring at nanomolar concentration upon low-dose ionizing radiation (LDIR) (<100 mGy). In view of the recent recognition of HO as a central redox signaling molecule that, likewise, is maintained in the nanomolar range in cells, we propose a role for HO in radiation hormesis. LDIR is capable of utilizing known molecular redox master switches such as Nrf2/Keap1 or NF-κB/IκB to effect adaptive resistance.

Evidence That Lifelong Low Dose Rates of Ionizing Radiation Increase Lifespan in Long- and Short-Lived Dogs.

After the 1956 radiation scare to stop weapons testing, studies focused on cancer induction by low-level radiation. Concern has shifted to protecting "radiation-sensitive individuals." Since longevity is a measure of health impact, this analysis reexamined data to compare the effect of dose rate on the lifespans of short-lived (5% and 10% mortality) dogs and on the lifespans of dogs at 50% mortality.

The quest to exploit the Auger effect in cancer radiotherapy - a reflective review.

To identify the emergence of the recognition of the potential of the Auger effect for clinical application, and after tracing the salient milestones towards that goal, to evaluate the status quo and future prospects. It was not until 40 years after the discovery of Auger electrons, that the availability of radioactive DNA precursors enabled the biological power, and the clinical potential, of the Auger effect to be appreciated. Important milestones on the path to clinical translation have been identified and reached, but hurdles remain.

Quantification of Adaptive Protection Following Low-dose Irradiation.

The question whether low doses and low dose-rates of ionizing radiation pose a health risk to people is of public, scientific and regulatory concern. It is a subject of intense debate and causes much fear. The controversy is to what extent low-dose effects, if any, cause or protect against damage such as cancer.

Commentary on Inhaled (239)PUO2 in Dogs - A Prophylaxis Against Lung Cancer?

Several studies on the effect of inhaled plutonium-dioxide particulates and the incidence of lung tumors in dogs reveal beneficial effects when the cumulative alpha-radiation dose is low. There is a threshold at an exposure level of about 100 cGy for excess tumor incidence and reduced lifespan. The observations conform to the expectations of the radiation hormesis dose-response model and contradict the predictions of the LNT hypothesis.

Cancer Mortality Among People Living in Areas With Various Levels of Natural Background Radiation.

There are many places on the earth, where natural background radiation exposures are elevated significantly above about 2.5 mSv/year. The studies of health effects on populations living in such places are crucially important for understanding the impact of low doses of ionizing radiation.

Commentary: ethical issues of current health-protection policies on low-dose ionizing radiation.

The linear no-threshold (LNT) model of ionizing-radiation-induced cancer is based on the assumption that every radiation dose increment constitutes increased cancer risk for humans. The risk is hypothesized to increase linearly as the total dose increases. While this model is the basis for radiation safety regulations, its scientific validity has been questioned and debated for many decades.

Hemopoietic response to low dose-rates of ionizing radiation shows stem cell tolerance and adaptation.

Chronic exposure of mammals to low dose-rates of ionizing radiation affects proliferating cell systems as a function of both dose-rate and the total dose accumulated. The lower the dose-rate the higher needs to be the total dose for a deterministic effect, i.e.

The Auger Effect in biology and medicine. Looking back.

Purpose: The Auger Effect entered biology in 1967 in a quantal step leading to a burst of experimental work on basic and applied cell- and molecular biology and medicine, which is briefly described.

Conclusion: The relevance of this work again appears in the agenda of the 7th International Symposium on Physical, Cellular, Molecular and Medical Aspects of Auger Processes, held in Jülich, Germany, in 2011.