Potential role of microdosimetry for future ICRP recommendations

The International Commission on Radiation Units and Measurements (ICRU) recently published a new report on microdosimetry entitled 'Stochastic nature of radiation interactions: Microdosimetry'. It provides a comprehensive description of the basic concepts and theories, computational and experimental procedures, and applications of microdosimetry. Evaluation of the relative biological effectiveness (RBE) stands out as one of the most crucial applications of microdosimetry. While such applications have primarily been dedicated to medical physics, the field of radiological protection (RP) also demands the assessment of RBE particularly for tissue reactions due to a recent suggestion made by ICRU and ICRP to change the definition of the operational quantities. This article presents a summary of our recent studies on evaluating RBE for skin reactions and diseases of the circulatory systems based on a microdosimetric kinetic model, together with discussions on the potential role of microdosimetry in the determination of RBE weighting factors used for RP purposes in the future.