The NRPA welcomes this report that provides useful clarification on how the Commission’s nascent environmental protection guidance fits within their broader radiological protection framework, its relationship to the principles of justification, optimization and limitation and its relevance when considering types of exposure situation.
The ICRP’s stated aims for environmental protection are those of “….preventing or reducing the frequency of deleterious radiation effects to a level where they would have a negligible impact on the maintenance of biological diversity, the conservation of species, or the health and status of natural habitats, communities and ecosystems”. In this respect, the argument (A77) is forwarded that although “undoubtedly the major requirement will be the need to make evaluations at the population or ecosystem level” that it is, nevertheless, appropriate to focus on radiation effects at the individual level because, among other considerations, effects on populations and higher levels of biological organization are “mediated via effects on individuals of that population”. This is, however, a debatable point and it remains quite conspicuous that the protection objectives, defined above and set at higher scales of biological organization than the individual level epitomizing the use of Reference Animals and Plants (RAP), are not directly addressed in the ICRP’s approach.
As the ICRP is no doubt aware, there have been significant modern developments in potentially complementary approaches that might mitigate these shortcomings in the RAP-based methods. In particular, ecosystem-based approaches which consider interactions between different levels of biological organization with greater focus on the structure and function of the ecosystem through analyses of processes such as primary productivity, energy transfer, nutrient flow and decomposition, offer great potential. Such approaches have been applied with initial success in scientific fields dealing with, for example, protection of biodiversity and the International Union of Radioecology have recently provided a comprehensive summary with applications of such methods in a newly published report (IUR, 2012). The ICRP’s arguments would be more persuasive were they to include a more explicit acknowledgement of these developments, recognizing the limitations of the RAP-based methods and exploring how the current system might be refined to encompass a more functional or ecosystem process based approach to environmental assessment.
Reference
IUR (2012). "Towards an ecosystem approach for environment protection with emphasis on radiological hazards". IUR Report n° 7 :2012. International Union of Radioecology.
Convention on Biological Diversity (CBD), Ecosystem Approach Principles, esp. principal no 5.http://www.cbd.int/ecosystem/principles.shtml