The overall objective of RA2 is to improve the parameterisation of radionuclide transfer in the environment through a systematic implementation of dynamic approaches and to refine extrapolation methods. The initial strategy involved the formulation of three research themes encompassing bespoke research questions and hypotheses. It was anticipated that addressing these themes would facilitate a reduction in uncertainty and allow better characterization of variability in the parameters defining radionuclide transfer. The research focused especially on:
- Mobility of radionuclides, taking speciation into account;
- Uptake and accumulation in organisms – influence of environmental factors, and
- Uptake and accumulation in organisms – influence of biological factors,
covering naturally occurring radionuclides as well as transuranics and fission products.
RA2 is an important link between all other RAs with the requirement to couple information between Source Term and Release Scenarios (RA1) and transfer, the efficacy of studying transfer in tandem with biological response (RA3), coupling toxicokinetics to toxicodynamics, and the fact that transfer forms an integral part of Risk Assessment (RA4). Thus, RA2 includes field work performed in Norway or other countries, and is focused on improved understanding of dynamic transfers in relation to aquatic ecosystems and terrestrial ecosystems, to replace transfer constants based on equilibrium concepts with time functions.