[Transfer of radiocesium into rabbit meat and its excretion]

The uptake of radiocesium Cs-137 in rabbit's muscle and its clearance were studied following the 24 days long ingestion of hay naturally contaminated as a consequence of the Chernobyl accident. The average radioactivity of hay was 2,294 +/- 345 Bq/kg and the daily intake was 0.5 kg. It was found that after 20 days of ingestion the muscle radionuclide concentration equilibrated with that of the feed. The transfer coefficient Tf describing the fraction of the daily intake of Cs-137 found in a kilogram of rabbit's muscle was calculated: Tf = 0.29 +/- 0.15 d/kg. The biological Cs-137 clearance rate (after finishing the feeding with contaminated diet) was found to be ruled by two biological half-lives: Tb1 = 1.5 days and Tb2 = 66 days and fitting the following retention equation: At = 0.66.e-0.46.t + 0.34.e-0.01.t It means that 5 days after removing the animals from contaminated diet the amount of Cs-137 can be expected as 30% of the initial one.