Assessment of Tritium Behavior in Man Using a Modified Three-Compartment Model

In this study, on the basis of many human tritium metabolic data accumulated in the OKTAVIAN facility until now, the characteristics of the measured data have been analyzed for bioassay samples of urine, exhaled water and distilled water from urine. It has been found that the tritium concentration of exhaled water is equal to that in distilled water from urine. As a result, a new method has been developed to follow up each metabolism of two chemical forms, that is, free water tritium (FWT) and organically bound tritium (OBT) components in urine. In estimating the amount of retained tritium in the human body for a long time with their bioassay samples, it would vary depending upon the selection of samples. Moreover, a new tritium metabolic model has been developed by modifying a well-known, conventional three-compartment model, and verified with the measured data.