SYMBIOSE : A Modeling Platform for Environmental Chemical Risk Assessment.

M.A. Gonze, L. Garcia Sanchez, P. Boyer, C. Mourlon, C. Tamponnet
Actes de la conférence "3rd International Symposium on the Protection of the Environment from Ionising Radiation -22/26 juillet 2002 -Darwin (Australia)." p.266-277

Environmental systems are considered among the most complex ones because they involve a large number of diverse components, interactions, scale issues, spatial heterogeneity and significant sources of uncertainty. An Environmental Chemical Risk Assessment (ECRA) require therefore the integration of a wide range of data and modeling approaches, while accounting for sources and propagation of uncertainties in the system. Further, the level of detail to be achieved in an assessment depends mainly on environmental management objectives and the difficulty of adequately describing exposure, toxicity and other properties of the chemicals with site-specific data. This can range from simplistic conservative analyses to more realistic spatio-temporal modeling approaches. As a consequence, there is a pressing need for integrated, flexible (and user-friendly) tools that could adapt to this shifting and expanding assessment context. The SYMBIOSE project aims at developing such a modeling and simulation platform, for assessing the fate, transport and effects of chemicals - radionuclides and heavy metals, mainly - on humans and biota, in a multi-media environment. The various aspects of an environmental chemical risk assessment process, and existing relationships between them, are first revisited in a comprehensive way with emphasis on valuable modeling techniques. The modeling approach that will be implemented in the platform is then described through keystone aspects such as conceptual, mathematical and spatial modeling aspects. Finally, some key ideas about the object-oriented software architecture that is foreseen are presented.