A toxicokinetic model for fish including multiphase sorption features

In the scientific field of physiologically based toxicokinetic modeling the complexity of the model used depends on the complexity of the problem to be handled, leading to a broad range of existing models from simple 1-box models to complex multicompartment models. Most of these models work with lumped parameters, for example, an uptake efficiency parameter that can only be obtained with a fit of experimental data. The authors' goal was a model that is completely based on well-defined physiological and physicochemical parameters. Lumped parameters fitted on training data sets would limit the model's applicability. This would enable a new view on process understanding for uptake, distribution, and elimination procedures. Eventual goals are a better localization of chemicals within the organism itself, and to set the stage for future extensions toward ionic compounds and active transport across membranes. The model evaluation reported in the present study has shown that uptake, clearance, and bioaccumulation data for nonpolar chemicals are well predicted. Environ Toxicol Chem 2017;36:1538-1546. © 2016 SETAC.