Comparison of tritium metabolism in rat following single or continuous ingestion of tritium labeled wheat versus tritiated water.

The incorporation and distribution of tritium were measured in rats exposed to tritiated wheat by single or continuous ingestion and compared with those in rats exposed to tritiated water. After single ingestion of tritiated wheat, the concentrations of organically-bound tritium (OBT) in rat tissues were about 20-30 times higher than those after single ingestion of tritiated water. In the case of a continuous ingestion, the amount of OBT in the tissue of rat exposed to tritiated wheat was about 6-ll times larger than when exposed to tritiated water. After acute or chronic exposure of tritiated wheat, OBT was not uniformly distributed among the tissues and the concentrations were relatively high in the liver and low in the muscle and the brain. When the present result was compared with other''s which examined the distribution of OBT in various tissues of animals after administration of some different kinds of tritiated food, it was found that their distribution patterns were similar.