Protection radiologique de l'environnement: sur la nécessité de renforcer le concept d'écosystème en radioécologie
Titre du congrès :INSINUME 2008 - International Symposium on In Situ Nuclear Metrology as a Tool for Radioecology
Ville du congrès :Rabat
Date du congrès :13/10/2008
The last century has prompted an unprecedented raise in the world population and its associated activities which impact the environment, whether through dramatic withdrawals (forest, fish stocks, ...). Facing these problems in turn prompted various efforts of regulations, often fragmented, and aimed at various aspects of the protection of the environment. These regulations are designed precisely to prevent such problems to arise... but once they were already there. This often proves to be very late, if not too late, to counteract the environmental detriment. Building capacity for anticipation is paramount in the sciences of risk, that is to be able to access prevention through prior understanding. The system of radiological protection of the environment that is currently under development is one contribution to this general need to protect the environment appropriately. Dominated by operational goals, it emphasises conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, ...), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances,... Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This paper will discuss the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This will lead in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning.