Extrapolation of physiological parameters for physiologically based simulation models

Masses of organs and fluids, pulmonary ventilation and cardiac output and its distribution are the basic input data used in physiologically based pharmacokinetic models. Since these parameters are rarely measured in pharmacokinetic studies, the values found in reference books or extrapolated to meet the specific exposure conditions are used in the models. In this review of the extrapolation of pertinent physiological parameters, power equations for scaling across mammals, adjustments to body build (lean body mass) and physical activity of humans and their significance for risk assessment of human exposure to solvents using animal data are assessed.