Effective Dose Coefficients for Intakes of Uranium Via Contaminated Wounds for Reference Adults.

Abstract

Effective dose coefficients for intakes of uranium radionuclides via contaminated wounds have been calculated for reference adults following the procedures in the ICRP 103 series. The number of transformations in each source region for all members of the radioactive series from time of intake to 50 y post intake are calculated by coupling the NCRP 156 wound model to the ICRP 137 systemic models and ICRP 100 human alimentary tract model. Together with the ICRP 107 nuclear decay data for dosimetric calculations, the ICRP 133 specific absorbed fractions are implemented to calculate the radiation-weighted S coefficient deposited in each target organ or tissue from each transformation in each source region. Effective dose coefficients for different categories of intake materials via contaminated wounds are calculated for the three major uranium isotopes-238U, 235U, and 234U. Originating from the combined effects of the new absorbed fractions, biokinetic and dosimetric models, the new coefficients are generally reduced by a percentage of 23-28% as compared to the old ones. The new dose coefficients benefit the assessment of internal exposures for intakes of uranium via contaminated wounds in actual applications.