The behavior of marine distribution coefficients is analyzed with the help of numerical experiments and ana-lytical solutions of equations describing kinetic models
for uptake/release of radionuclides. The difficulties in measuring true kd in a marine environment perturbed by an external radionuclide source are highlighted.
Differences between suspended matter and bed sediment kd are analyzed. The performances of different kinetic models (1-step/2step; single-layer/multi-layer) are
studied in model/model and model/experiment compar-isons. Implications for the use of models to assess radioactive contamination after an emergency are given; as
well as recommendations when kd data are compiled in order to create a useful databaseInternational Atomic Energy Agency (IAEA) KIOST PE9961
