Internal Dosimetry - Enhancements in Application

The idea of the IDEA project aimed to improve assessment of incorporated radionuclides through developments of more reliable and faster in-vivo and bioassay monitoring techniques and making use of such enhancements for improvements in routine monitoring. In direct in-vivo monitoring technique, the optimum choice of the detectors to be applied for different monitoring tasks has been investigated in terms of material, size and background in order to improve conditions, namely to increase counting efficiency and reduce background. Detailed studies have been performed to investigate the manifold advantageous appllications and capabilities of numerical simulation method for the calibration and optimisation of in-vivo counting systems. In bioassay measurements, the use of inductively coupled plasma mass spectrometry (ICP-MS) can improve considerably both the measurement speed and the lower limit of detection currently achievable with alpha spectrometry for longlived radionuclides. The work carried out in this project provided detailed guidelines for optimum performance of the technique of ICP-MS applied mainly for the determination of uranium and thorium nuclides in excreta.