Internal dose calculations with the new biokinetic models of the ICRP

During the past decade, the ICRP made major revisions in its recommendations regarding protection from ionising radiation and advised the use of new models for estimating doses due to intake of radionuclides. A new internal Dosimetry code (InDose) is presented which employs all the new biokinetic models together with the new respiratory tract (RT) model and the gastrointestinal tract (GI) model. The code makes use of a generalised form of these new biokinetic models which enables the use of any of them. The code has been used to assess intakes and doses for the 3rd European Intercomparison Exercise on Internal Dose Assessment. A detailed study of one of the test cases of this exercise is presented. Our code using the new plutonium biokinetic model and LUDEP gave similar results. InDose, however, provides a way to insert consistent changes in the models in order to make estimations under non-standard conditions. The new biokinetic model has been found to give better agreement with measured data than the old (ICRP 30) model.