The draft Radiation Detriment Calculation Methodology is now available for public consultation. We welcome comments from individuals and organisations.
The draft document can be downloaded from the ICRP website. Comments must be submitted through the ICRP website no later than May 1, 2020.
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.