Public Consultation Period Extended for Available Draft Reports


The public consultation period for the draft reports on Radiation Detriment Calculation Methodology and Cancer Risk from Exposure to Plutonium and Uranium has been extended.  Interested parties can now provide comments until 5 June 2020 and 10 July 2020, respectively. Both reports can be accessed by visiting the Consulations page of the ICRP website.

Questions and inquries can be directed to Kelsey Cloutier, Development and Communications Manager for ICRP.



Radiation detriment is a concept used to quantify the harmful stochastic effects of low-level radiation exposure to the human population. It is determined from lifetime risk of cancer for a set of tissues and organs taking into account their severity in terms of lethality, quality of life, and years of life lost. It also considers heritable effects. The radiation detriment is estimated as a sex- and age-averaged risk indicator for a composite reference population. This report provides a historical review of the detriment calculation methodology adopted by the International Commission on Radiological Protection (ICRP) since Publication 26 and a detailed description of the whole computation process used in Publication 103. It clarifies data sources, risk models, computational methods and rationale for the choice of parameter values. The parameters that have the greatest influence on the radiation detriment calculation are also identified based on a series of sensitivity analyses. They include dose and dose-rate effectiveness factor (DDREF), age at exposure, sex difference and lethality fraction. Although the current scheme of radiation detriment calculation is well established, it may need to evolve to take into account changes in baseline reference data (mortality, cancer incidence and lethality) in recent decades and progress in scientific understanding of radiation health effects. In this perspective, the report suggests ways to update and improve the estimation of key parameters for the calculation of radiation detriment, such as the reference population data and cancer severity. There is also room for improvement in cancer risk models based on the accumulation of recent epidemiological findings. Finally, the importance of improving the comprehensibility of the radiation detriment concept and the transparency of its calculation methodology is emphasised.


The objective of this publication is to provide a detailed review of results from recent epidemiological studies of cancer risk from exposure to plutonium and uranium, and how these results relate to the assumptions currently used for protection against alpha radiation. For plutonium, the two main studies are of the cohorts of workers employed at the nuclear installations at Mayak in the Russian Federation and at Sellafield in the United Kingdom. The analysis of the Mayak cohort provides an estimate of the slope of the dose-response for lung cancer risk, while at lower levels of plutonium exposure, the Sellafield cohort provides results that, within relatively large confidence intervals, are consistent with those for the Mayak cohort. Results from the Mayak cohort also show an association between plutonium exposure and risks of liver and bone cancers, but not of leukaemia. Lifetime excess risk of lung cancer mortality has been calculated for scenarios of acute and chronic inhalation of plutonium nitrate and plutonium oxide, similarly to that done previously for radon and its decay products in Publication 115. Estimated lifetime excess risks of lung cancer mortality per unit absorbed dose are close to those derived from miner studies for exposure to radon and its progeny, and are compatible with the assumption of a radiation weighting factor of 20 for alpha particles. Epidemiological studies of cancer risk associated with uranium exposure have been conducted among cohorts of European and North American workers involved in the nuclear fuel cycle. Current results do not allow the reliable derivation of dose-risk models for uranium for any cancer type. Continuation of efforts to improve dose assessment associated with uranium and plutonium exposure is recommended for future research.