Key Question: What is required for the integration of human and non-human protection and how might it be approached?
A well developed, mature system for the radiological protection of humans has existed for decades. In recent years a similar system intended to provide radiation protection for wildlife has begun to evolve. In general, the processes involved in the transfer of radionuclides to humans and wildlife are essentially the same. To date however, the development of models (and their underpinning databases) that can describe and predict the transfer of radionuclides to humans and wildlife have occurred in isolation from one another. In a similar vein, there are also differences in dosimetry. Virtually all of the current wildlife assessment models considering organisms as simple homogeneous shapes compared to the consideration of organ doses for humans.
Some models used to describe transfer of radionuclides within the environment incorporate the processes controlling that transfer (e.g. water or soil chemistry) but many, particularly those describing transfer to wildlife, employ simple ratios to describe this transfer. Although such approaches are often fit for purpose, the development of models describing transfer utilizing the processes governing that transfer would allow a much wider application. As an example, generic soil to plant transfer ratios are vulnerable in how appropriate the values used are to the specific scenario being considered. A model describing the same transfer but using soil characteristics, such as pH, organic matter content or cation exchange capacity, should be applicable for any situation where those parameters are known.
Many gaps exist in our knowledge of the transfer of radionuclides within the environment. It is unlikely that specific data for transfer of all radionuclides to all possible wildlife or plant species can ever be generated. Techniques exist whereby radionuclide transfer can be estimated based on parameters which are easier to generate data for, such as body mass, which may address the lack of specific radionuclide data.
STAR will contribute to the updating and improvement of the ERICA Assessment Tool developed under an earlier EURATOM programme. The Tool is now used in assessments by regulators, industry and researchers across the world. The Tool was updated in autumn 2014 with revised parameter databases and some changes to the reference organism lists. Click hereto see some information on these changes.
Integrated Human & Non-Human Radiation Protection
An objective of STAR is to establish foundations for the development of decision support tools for integrated human and wildlife risk assessment by:
- Developing, testing and optimising a conceptual model for integrated human and wildlife assessment
- Using process-oriented mathematical/numerical modelling for integrated human and wildlife assessments
- Analysing current developments in the area of wildlife dosimetry and producing recommendations on improving wildlife dosimetry
- Reviewing and analysing initiatives and activities in the area of integrated protection and assessment
- Critically comparing and contrasting the current system of human radiation protection with the developing system of protection for non-humans within the context of integration
- Description of the ERICA Assessment Tool for radiation protection of non-human species
- The International Commission on Radiological Protections (ICRP) - Task Group on Integrating the ICRP System of Protection for Humans and Non-human Species
- The International Union of Radioecology’s (IUR) - Task group on the Ecosystem Approach to Environment Protection
- The International Atomic Energy Agency’s (IAEA) - Coordination Group on Radiation Protection of the Environment
- The International Atomic Energy Agency’s (IAEA) - EMRAS II Working Group on model validation for biota dose assessment
- Other Working Groups are considering human assessment models
- PROTECT project - EURATOM project which included some consideration of the integration of human and wildlife assessments, see especially paper by Copplestone et al. (2010) with relevance relevant to this workpackage of STAR.
This workpackage is co-ordinated by Astrid Liland of NRPA.
Picture adapted from ICRP Publication 108