Effective dose conversion coefficients for radionuclides exponentially distributed in the ground

Saito, Kimiaki  ; Ishigure, Nobuhito*; Petoussi-Henss, N.*; Schlattl, H.*

In order to provide fundamental data required for dose evaluation due to environmental exposures, effective dose conversion coefficients were calculated for a number of potentially important radionuclides, assuming exponential distribution in ground, over a wide range of relaxation depths. The conversion coefficients were calculated for adults and a new-born baby on the basis of dosimetric methods that the authors and related researchers have previously developed, using Monte Carlo simulations and anthropomorphic computational phantoms. The differences in effective dose conversion coefficients due to body size between the adult and the baby were found to lie within 50%, for most cases. It was shown that the implementation into the computation of the tissue weighting factors and the adult reference computational phantoms of ICRP Publication 103 does not significantly influence the effective dose conversion coefficients of the environment.