A comparison of the predictions of the ICRP 56 dosimetric model for plutonium with those calculated using other age-related models and using the ICRP 48 model

Abstract

Current annual limits on intake (ALIS) and other secondary dose limits for plutonium were initially calculated using the mathematical models and biokinetic data specified for this bone-seeking radionuclide by the International Commission on Radiological Protection (ICRP) in its Publication 30 (ICRP 1979). These dosimetric data and models were subsequently revised by the ICRP in its Publication 48 in order to better reflect the available human data for plutonium (ICRP 1986), but the revisions did not have a significant effect on the values of any secondary dose limits. The main model revisions recommended in ICRP 48 were a reduction in the assumed retention half-time of plutonium in the skeleton from 100 to 50 years, and in the liver from 30 to 20 years. More recently, another model for plutonium dosimetry has been published by ICRP in its Report 56. The ICRP 56 model is a physiological model, is age-related and was developed for dose assessment purposes in populations rather than workers. The ICRP 48 and ICRP 56 models for plutonium are compared with each other and with the comparable predictions of the Oak Ridge and Harwell/Chilton dosimetric models using a common computer code.