The latest and largest study of nuclear workers published in the British Medical Journal in June of this year (1) must be a shocking revelation to the scientists and politicians who believe that nuclear power and radioactive exposures have been well understood and modelled, and that the laws regulating radiation exposures are safe. The research carried out by Dr Busby in the last 30 years which showed that the official radiation risk models are fatally unsafe has now been vindicated by the nuclear system epidemiologists themselves.
The paper in the British Medical Journal concedes in its abstract:
The summary estimate of excess relative rate solid cancer mortality per Gray (unit exposure) is larger than estimates currently informing radiation protection. Some evidence suggests a steeper slope for the dose response association in the low dose range, rather than the full dose range.
What this means is that the current radiation risk model, which underpins all radiation exposure laws in Europe, USA and UK is dead in the water. The error is not small.
The graph shown by the researchers makes it difficult to see what happens in the low dose range. For that reason, Dr Busby replotted the low dose range in the graph below.

Excess Cancer Mortality Relative Risk (ERR) as a percentage, from the INWORKS study showing the low dose region below 100mGy. Error bars are shown in red. The green line shows the assumed linear no threshold dose response based on the full dataset [Green Audit]

There is a remarkable increase in risk in the 0-10mGy region followed by a sharp fall below 30mGy (see Fig 1).

As the paper stands, the ERR/Gy reported by the authors for the whole dose range (0.52) increased to 1.38 for the 0-50mGy cohort and if we conservatively assume a mean dose in this group of 25mGy the ERR/Gy in this low dose region is 40. This must be compared with the current ICRP ERR of 0.04 (ICRP 2007). The resulting error in the risk coefficient is therefore 1000-fold. However, focusing on the very low dose region, if the ERR is 0.05 (5%) at 7.5mGy as seen in Fig 1 (and this is statistically significant) it points to a much greater ERR/Gy of about 133. That is to say, the slope of the dose response from zero to about 10mGy is very much greater than the slope based on 0-50mGy.
Because of these results, black letter law, requires a reassessment of Justification for exposures to radiation. The EU Basic Safety Standards Directive, for example, requires:
Member States shall consider a review of existing classes or types of practices with regard to their justification whenever there is new and important evidence about their efficacy or potential consequences. (BSS 2013).

There are also issues regarding legal decisions that have been made for some 20 years denying pensions to nuclear test veterans on the basis of the ICRP risk model. Radiation pensions appeals systematically failed because the Tribunals were informed by government experts that the doses were too low (Abdale 2016).

The new evidence shows that the current model, because of its reliance on the Linear No Threshold (LNT) assumption and its connection with the now discredited Japanese Lifespan Study (Busby 2021, 2022), should now be replaced.

Dr Busby has written to the British Medical Journal pointing this out.
References and further information

Leonard Abdale and Others vs. Secretary of State for Defence. Executive Summary of the Determination. https://www.judiciary.uk/uploads/2016/12

Busby Christopher. Ionizing radiation and cancerthe failure of the risk model. Cancer Treatment and Research Communications. 31 (2022) 100565. DOI https://doi.org/10.1016/j.ctarc.2022.100565
Busby Christopher (2021) The Hiroshima A-Bomb Black Rain and the Lifespan Study; a Resolution of the Enigma, Cancer Investigation, 2021 DOI: 10.1080/07357907.2021.1977818

BSS 2013. Basic Safety Standards Directive of the European Union. Directive 96/29 Euratom. Updated to Council Directive 2013/59/Euratom of 5 December 2013 Article 19(2) Justification.

ICRP. The 2007 recommendations of the International Commission on Radiological Protection ICRP103. (2007) Elsevier: Amsterdam

Richardson David B. et al (2023) Cancer Mortality after low dose exposure to ionising radiation in workers in France, the United Kingdom, and the United States (INWORKS): cohort study by David B. Richardson et al. BMJ 2023;382;e074520