Abstract
Internal dose coefficients for ingestion and inhalation of radioiodine were preliminarily calculated considering the metabolic characteristics of Japanese. In the calculation, the fractional uptake by thyroid (f) of iodine entering blood and biological half-life in thyroid (Tb) were reflected among the data peculiar to Japanese concerning thyroid structure and iodine metabolism in thyroid. A metabolic model for iodine used here was based on the three-compartment recycle model described in the ICRP Publication 30. As to the parameters of f and Tb, the values of 0.2 and 40 days reported for Japanese were used instead of those of 0.3 and 80 days adopted by ICRP.
The dose coefficients for Japanese calculated here are smaller than those for Reference Man of Caucasian. The author expects that the coefficients will be used for radiation protection purpose for workers and adults of the public in Japan.
