DERIVATION OF SOIL TO PLANT TRANSFER-FACTORS OF RADIOCESIUM IN NORTHERN GREECE AFTER THE CHERNOBYL ACCIDENT, AND COMPARISON WITH GREENHOUSE EXPERIMENTS

Radiocesium contamination of cereals, due to the Chernobyl accident, was systematically studied in two selected experimental agricultural farms in Northern Greece for the years 1987, 1988 and 1989. Radiocesium contamination of all annual crops is very low, of the order of 1 Bq kg-1, and appears to be, for the first 3 years after the Chernobyl accident, time independent, the differences lying within the experimental error. Transfer factors, relating radiocesium deposition to contamination of crops, are deduced from the experimental results. Results are also discussed in the framework of UNSCEAR's empirical model, and the corresponding parameters are deduced. In addition, greenhouse experiments show that the obtained Transfer Factors are independent of the initial radiocesium deposition and that radiocesium from the Chernobyl fallout behaves differently from usual experimental sources, such as (CsCl)-Cs-137.