Workers decommissioning the Fukushima-Daiichi
nuclear power plant damaged from the Great East Japan Earthquake and resulting tsunami are at risk of injury with possible contamination from radioactive heavy atoms including
actinides, such as
plutonium. We propose a new methodology for on-site and rapid evaluation of heavy-atom contamination in
wounds using a portable X-ray fluorescence (XRF) device. In the present study, stable lead was used as the model contaminant substitute for radioactive heavy atoms. First, the
wound model was developed by placing a liquid blood phantom on an
epoxy resin wound phantom contaminated with lead. Next, the correlation between the concentration of contaminant and the XRF peak intensity was formulated considering the thickness of blood exiting the
wound. Methods to determine the minimum detection limit (MDL) of contaminants at any maximal equivalent dose to the
wound by XRF measurement were also established. For example, in this system, at a maximal equivalent dose of 16.5 mSv to the
wound and blood thickness of 0.5 mm, the MDL value for lead was 1.2 ppm (3.1 nmol). The radioactivity of 239Pu corresponding to 3.1 nmol is 1.7 kBq, which is lower than the radioactivity of 239Pu contaminating
puncture wounds in previous severe accidents. In conclusion, the established methodology could be beneficial for future development of a method to evaluate
plutonium contamination in
wounds. Highlights: Methodology for evaluation of heavy-atom contamination in a
wound was established. A portable X-ray fluorescence device enables on-site, rapid and direct evaluation. This method is expected to be used for evaluation of
plutonium contamination in
wounds.