Retrospective Dosimetry and Dose Reconstruction of Ionizing Radiation

Abstract

The article concerns retrospective dosimetry and dose reconstruction and contains definitions, description of basic principles employed for retrospective assessment of doses, as well as practical considerations for application of retrospective dosimetry. Dose reconstruction is retrospective assessment of doses received by humans in the course of past exposure events. Retrospective dosimetry comprises various kinds of techniques falling into broad categories of biodosimetry, instrumental dosimetry, and analytical (‘time-and-motion’) dosimetry. Both biological and instrumental dosimetries use markers (biological or physical), which are caused by ionizing radiation in amounts (quantity and concentration) proportional to absorbed dose. Analytical dosimetry uses models and relies on radiation field data and reconstruction of itinerary (motions) of a person. Biodosimetry is based on biological markers of radiation (i.e., stable and unstable chromosome aberrations, and somatic mutations) in biological tissues, while instrumental dosimetry scores physical effects (i.e., creation of paramagnetic centers or populating electronic traps) in crystalline matter. Retrospective dosimetry techniques can be characterized by a set of parameters (i.e., sensitivity threshold and accuracy, effect of bias and confounding factors, availability of samples, etc.), which determine applicability of a given technique under particular circumstances. Most practical dose reconstruction methods are considered from the point of view of those parameters. Application areas and examples of utilization are given for most common dose reconstruction methods.