This is a reflection from a certified health physicist regarding his becoming aware, during his 40-year career, that the linear no-threshold (LNT) model and the associated As Low As Reasonably Achievable concept have no scientific basis and make no positive contribution to radiation safety. They should be replaced by an alternative, scientifically based model that includes a threshold, below wh...

The Linear Non-Threshold (LNT) process is used by virtually all governmental agencies to compute incidence of cancer as a consequence of exposure to a carcinogen. This comment applies the concept of Best Available Science (BAS) Metrics for Evaluation of Scientific Claims (MESC) derived from BAS to issues related to reliability of LNT hypothesis. This paper identifies the level of maturity of th...

The prime concern of radiation protection policy since 1959 has been protecting DNA from damage. The 1995 NCRP Report 121 on collective dose states that since no human data provides direct support for the linear no threshold hypothesis (LNT), and some studies provide quantitative data that, with statistical significance, contradict LNT, ultimately, confidence in LNT is based on the biophysical ...

Organisms survive best, or show high fitness, in the habitats in which they most commonly occur, a phenomenon referred to as hormesis in the literature of toxicology. Examples of hormesis accumulate rapidly in the literature. However, a lack of underlying models has led many to doubt its existence, especially for ionizing radiation. The evolutionary model developed here indicates that all poten...

It is not true that successive groups of researchers from academia and research institutions-scientists who served on panels of the US National Academy of Sciences (NAS)-were duped into supporting a linear no-threshold model (LNT) by the opinions expressed in the genetic panel section of the 1956 "BEAR I" report. Successor reports had their own views of the LNT model, relying on mouse and human...

This letter comments on the ongoing re-evaluation of the dose and dose rate effectiveness factor (DDREF) equal to 2.0, currently recommended by the International Commission on Radiological Protection. The topics of DDREF and threshold are related to the linear no-threshold theory (LNT), which does not take into account that DNA damage and repair are in dynamic equilibrium probably reached in a ...

Introduction: Radiation effects observed in cells that are not irradiated are known as non-targeted effects.  Radiation induced bystander effect (RIBE) as a kind of non-targeted effect has been introduced in recent  years.  RIBE  occurs  in  unexposed  cells  which  are  related  to  adjacent  or  distant  irradiated  cells.  RIBE  contradict with "target theory" which necessitates radiation tr...

Maurice Tubiana, MD Ludwig E. Feinendegen, MD Chichuan Yang, MD Joseph M. Kaminski, MD T he carcinogenic risk induced by low doses of ionizing radiation is controversial. It cannot be assessed with epidemiologic methods alone because at low doses the data are imprecise and often conflicting. Since the 1970s, the radiation protection community has estimated the risk of low doses by means of extr...

Some Areas of Ramsar, a city in northern Iran are among the world’s wellknown inhabited areas with highest levels of natural radiation. Annual exposure levels in these areas are up to 260 mGy y‐1 and the mean exposure rate is about 10 mGy y‐1 for a population of about 2000 residents. If elevated levels of natural radiation as high as a few hundred mSv per year is detrimental to health and...