DYNAMICS OF TRITIATED-WATER AND ORGANICALLY BOUND TRITIUM AFTER AN ACUTE TRITIATED-WATER INTAKE IN HUMANS

Tritiated water degrees (HTO) represents the most important occupation al and environmental exposures to tritium, as far as radiation protect ion is concerned. We have studied the dynamics of HTO and organically bound tritium (OBT) in urine, feces and blood from male workers at 10 0-300 d following an acute intake of HTO. Blood and cumulative 24 h ur ine and fecal samples were collected and analyzed for HTO and OBT. The activity concentrations of HTO in urine and HTO in feces were in equi librium and were representative of HTO in the body water (HTO in blood ). The ratio of bound tritium per gram hydrogen (Bq(.)gH(-1)) in organ ic matter in feces (OBTfeces) to urine (OBTurine) was 1.0 +/- 0.1. Sim ilarly, the ratios of OBTblood to OBTurine and OBTblood to OBTfeces we re 0.9 +/- 0.2 and 1.1 +/- 0.2, respectively. These results suggest th at, providing an equilibrium condition exists, a measurement of the tr itium activity per unit mass of organic matter in urine or feces can p rovide an assessment of the specific activity of tritium in the organi c fraction of the soft tissue.