NEW DOSE ESTIMATES FROM CHRONIC TRITIUM EXPOSURES

Estimates of the radiation dose from assimilation of tritium oxide, the common form of environmental tritium, are based on the assumption that tritium remains in body water until excreted. Analyses of deer tissues, however, indicate that chronic exposure to tritium causes significant labeling of organic molecules. The degree of labeling was determined from tritium assays of seven tissues (heart, liver, kidney, spleen, brain, muscle, and fat) from 52 deer collected on the Savannah River Plant site. In most tissues, the tritium-to-hydrogen ratios in both body water and the water of combustion of dried tissues were the same. This incorporation of tritium in the organic component of deer tissue results in whole body doses 1.4 to 1.5 times higher than estimated if only tritium in body water is considered. © 1969 Health Physics Society.