Book Description

At its fifty-ninth session (21-25 May 2012), the Scientific Committee considered a short review document on the biological mechanisms of radiation actions at low doses. That document, unlike the Committee's standard full evaluations, was not intended to be comprehensive; it was rather intended to highlight major advances in the field that would provide guidance for developing the Committee's future programme of work. The document concludes that understanding of the mechanisms of so-called non-targeted delayed effects is improving and that there is some evidence for differential responses in gene and protein expression for high- and low-dose radiation exposures, but there is a lack of consistency and coherence among reports. There is as yet no indication of a causal association of those phenomena with radiation-related disease. With regard to immune response and inflammatory reactions, there is a clearer association with disease, but there is no consensus on the impact of radiation exposure, particularly at low doses, on those physiological processes. While the document focuses on mechanisms relevant to carcinogenesis, some of the processes considered may be relevant for tissue reactions, and improved understanding may therefore be helpful for assessing the potential risk of non-cancer diseases at low and protracted exposures.