On the Th internal contamination by ingestion using the fission track method

We have been studying the animal internal contamination with fissionable elements. After uranium, the thorium was used by us in such studies. In this paper, the Th biodistribution, retention and elimination in the internal contamination by ingestion is described. Three Wistar-London breed rats were internally contaminated by ingestion with Th solution. Each of them has received an equal quantity corresponding to a Th Annual Limit Intake. The rats were sacrificed at different time intervals after contamination. Immediately after the sacrificing, their vital organs were sampled and calcined. In order to determine Th contents the samples were analysed by the fission track method. The obtained results led us to conclude on the Th biodistribution, retention and elimination by rats. The comparison between the U internal contamination and that using Th showed some interesting differences