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The article discusses the luminescence retrospective dosimetry characteristics of electronic components. Different types of surface-mount components like resistors, capacitors, or integrated circuits (ICs) in mobile phones were investigated to estimate which of them could demonstrate suitable radiation-induced luminescence signals. The study suggests that these components could be used as optically stimulated luminescence (OSL) dosimeters in radiation events. Further testing on dosimetry properties of other electronic components is in progress.

The article presents a study on radiation accident dosimetry using glass by thermoluminescence (TL) and electron paramagnetic resonance (EPR) spectrometry. The study used glass samples from 4 wristwatches and 20 mobile phone display windows washed with ethanol and cut in small pieces, then exposed to gamma irradiation. It shows the potential use of glass in retrospective dosimetry in radiation events with the EPR technique. Meanwhile, the TL technique warrants further investigation to correct dose estimation from significant fading and background.

The article presents a study on radiation accident dosimetry with plastics by means of electron paramagnetic resonance (EPR) spectrometry. The study used plastics from numerous personal belongings including eyeglasses, mobile phones, and watches which were cleaned with ethanol as necessary prior to exposure to irradiation. Among all the samples used, only the plastic from Hoya eyeglasses demonstrated the required characteristics for use in retrospective dosimetry. The study recommends further investigations on other existing plastic materials.

The article describes Simulation of External Source Accident with MEdical images (SESAME), a tool specific to dosimetric reconstruction of radiological accidents through numerical simulations which combine voxel geometry and the radiation-material interaction MCNP(X) Monte Carlo computer code with a user-friendly Graphical User Interface. It explores the experimental validation of the tool using a photon field. Information is given on the application of the tool to an accident which occurred in Chile in December 2005.

An abstract of the article "Q-Band Electron Paramagnetic Resonance Dosimetry in Micro Biosamples," by A. Romanyukha is presented.

For localized irradiation to hands, in case of sources accidentally handled, it is very difficult to estimate the dose distribution by calculation. Doses may reach several tens of grays, and the dose distribution is usually very heterogeneous. Until recently, doses in such situations could be estimated only by analysis of bone biopsies using Electron Paramagnetic Resonance (EPR) spectroscopy. This technique was used previously on surgical wastes or after amputation of a finger. In this case, the dose information was available in one or a few locations on the hand only, due to the limited number of biopsy fragments usually collected. The idea to measure free radicals (FRs) induced by radiation in nails to estimate a dose is not new, but up to now, no application cases were reported. As a matter of fact, the EPR analysis of nails is complex due to the presence of intrinsic signals and parasitic signals induced by the mechanical stress (when nails are collected), which overlaps the radio-induced components. In addition, the radio-induced FRs identified up to now are unstable and very sensitive to humidity. In these conditions, it was difficult to foresee any application for dosimetry with fingernails. Recently, stable radio-induced FRs in nails has been identified and an associated protocol for dose assessment developed. This protocol has been applied by the Institut de Radioprotection et de Sûreté Nucléaire on fingernail samples from victims of three different radiological accidents that occurred between 2008 and 2012 in different places.

As MOSFET (Metal Oxide Semiconductor Field Effect Transistor) detectors allow dose measurements in real time, the interest in these dosimeters is growing. The aim of this study was to investigate the dosimetric properties of commercially available TN-502RD-H MOSFET silicon detectors (Best Medical Canada, Ottawa, Canada) in order to use them for in vivo dosimetry in interventional radiology and for dose reconstruction in case of overexposure. Reproducibility of the measurements, dose rate dependence, and dose response of the MOSFET detectors have been studied with a Co source. Influence of the dose rate, frequency, and pulse duration on MOSFET responses has also been studied in pulsed x-ray fields. Finally, in order to validate the integrated dose given by MOSFET detectors, MOSFETs and TLDs (LiF:Mg,Cu,P) were fixed on an Alderson-Rando phantom in the conditions of an interventional neuroradiology procedure, and their responses have been compared. The results of this study show the suitability of MOSFET detectors for in vivo dosimetry in interventional radiology and for dose reconstruction in case of accident, provided a well-corrected energy dependence, a pulse duration equal to or higher than 10 ms, and an optimized contact between the detector and the skin of the patient are achieved.

Treatment of severe radiation burns remains a difficult medical challenge. The response of the skin to ionizing radiation results in a range of clinical manifestations. The most severe manifestations are highly invalidating. Although several therapeutic strategies (excision, skin grafting, skin or muscle flaps) have been used with some success, none have proven entirely satisfying. The concept that stem cell injections could be used for reducing normal tissue injury has been discussed for a number of years. Mesenchymal stem cells therapy may be a promising therapeutic approach for improving radiation-induced skin and muscle damages. Pre-clinical and clinical benefit of mesenchymal stem cell injection for ulcerated skin and muscle restoration after high dose radiation exposure has been successfully demonstrated. Three first patients suffering from severe radiological syndrome were successfully treated in France based on autologous human grade mesenchymal stem cell injection combined to plastic surgery or skin graft. Stem cell therapy has to be improved to the point that hospitals can put safe, efficient, and reliable clinical protocols into practice.