Transport of radiocaesium from a sheep's diet to its tissues.

Transfer coefficients for radiocaesium transport from a sheep's diet to blood, muscle, lung, liver, kidney, spleen heart, brain, rumen, intestines and fat were measured in a controlled experiment involving 50 adult ewes. The animals were fed dry grass and wheat, both contaminated with Chernobyl fallout debris, for a period of 60 days. During this period half of the animals were killed at regular intervals and samples of their blood and tissues were measured for radiocaesium concentration. The rest of the animals were returned to uncontaminated food and were monitored for radiocaesium concentration through periodic slaughtering for an additional 60 days. Transfer coefficients were extracted from the plateau reached at the end of the contamination phase. The data were also analyzed by means of a recently proposed linear multiple compartment model and transport rate parameters for each compartment were extracted. Transfer coefficients computed through the model's transport rate parameters show remarkable agreement with the experimentally obtained values.