Modification of 137Cs transfer parameters for soil mass loading on plant surfaces

Radionuclide contaminated soil adhered to plant surfaces can contribute to human ingestion dose. To determine this contribution, a method was established by using of 46Sc neutron activation analysis with a detection limit of 0.05 mg soil per g dry plant biomass. In the experiment the mass loading of soil on rye grass (Lolium perenne L.) and broad bean (Vicia faba L.) was investigated and the contribution from rain splash and wind erosion were evaluated separately. Soil retained on plant surfaces in field condition was 5.77 mg soil per g ray plant for rye grass and 9.51 mg soil per g dry plant for broad bean. Estimates of contribution from rain plash and wind erosion to soil contamination of plant during the experimental period are 68% and 32% for broad bean, 47% and 53% for rye grass respectively. Mass loading results from field studies indicate that soil adhesion on plant surfaces can contribute up to 23% of plant 137Cs contamination, after modification for soil mass loading the transfer factors decline in different extent, depending on 137Cs concentration in soil and the soil mass adhered to plant surfaces