Modelling Bioaccumulation in Aquatic Organisms and in Mammals

The assessment of bioaccumulation processes plays a significant role in the evaluation of chemical risks. The awareness of long-lasting and often irreversible effects of bioaccumulative chemicals on ecological and human targets encouraged the inclusion of bioaccumulation assessment in many national and international legislative frameworks. At the same time, various experimental and modelling approaches have been developed to estimate bioaccumulation metrics such as the bioaccumulation factor (BAF) or the biomagnification factor (BMF). In this chapter, the main processes governing bioaccumulation phenomena in selected aquatic organisms (phytoplankton, invertebrate and fish) and in terrestrial mammals are described, in particular those implemented in the corresponding models available in MERLIN-Expo tool for exposure assessment. The main objective is to describe the development of bioaccumulation models for organic and inorganic contaminants which takes into account recent progresses and which satisfactorily describes bioaccumulation of contaminants along food webs including phytoplankton, invertebrate and fish species for surface waters, and mammals for terrestrial systems, and also allowing dynamic and stochastic assessment according to MERLIN-Expo modelling features. The coupling of different aquatic biota models allows to recreate aquatic food web of different dimensions and complexity, while the coupling of terrestrial mammal model with plant models available in MERLIN-Expo permits to simulate the transfer of contaminants along simplified terrestrial food chains.