The Future of Radiological Protection


TG 91: Radiation Risk Inference at Low-Dose and Low-Dose Rate Exposure for Radiological Protection Purposes

Author(s): Werner Rühm 1, Tamara Azizova 2, Simon Bouffler 3, Bernd Grosche 4, Michiaki Kai 5, Mark P. Little 6, Kotaro Ozasa 7, Kazuo Sakai 8, Roy E. Shore 9, Quanfu Sun 10, Linda Walsh 11, Gayle Woloschak 12
( 1 Helmholtz Zentrum München, Germany; 2 Southern Urals Biophysics Institute, Russian Federation; 3 UK Health Security Agency (UKHSA), United Kingdom; 4 Former Federal Office for Radiation Protection (BfS), Germany; 5 Nippon Bunri University (NBU), Japan; 6 National Institutes of Health, USA; 7 Radiation Effects Research Foundation, Japan; 8 Tokyo Healthcare University, Japan; 9 New York University School of Medicine, USA; 10 National Institute for Radiological Protection, China; 11 University of Zurich, Switzerland; 12 Northwestern University, USA)



The detriment-adjusted nominal risk coefficients recommended by ICRP have been based, to a large extent, on data obtained from the atomic bomb survivors in Japan. ICRP introduced a Dose and Dose-Rate Effectiveness Factor (DDREF) of 2 to include in calculations of these risk coefficients for application at the low doses and low-dose rate exposures typical in radiological protection. The DDREF was included to account for the survivors’ single acute exposure, and because a linear quadratic instead of a linear risk to dose response was thought to be the most plausible biological model.

This paper summarizes the recent work of ICRP Task Group 91 on this topic. Task Group activities have included reviews of the history of low-dose and low-dose-rate effects, various exposure scenarios and their doses and dose rates, radiation-induced effects at the molecular, cellular, animal, and human level, and biologically-based mechanistic models of carcinogenesis. The Task Group performed a meta-analysis of low-dose-rate epidemiological studies, and re-analyses of published results on radiation-induced effects among animal models and among Japanese atomic bomb survivors.

Keywords: radiation-induced biological effects; low-dose effects; low-dose-rate effects



Bernd Lorenz

is that ok that one leaves a group out, when this group dominates the result?

Werner Rühm

Thanks for this question. In fact we left all of the studies out one-by-one. This exercise was done to understand the uncertainties behind the meta analysis; it also demonstrates that if just one study dominates, then one must be a bit more careful in interpreting the overall result.