Abstract
A PBPK model (physiologically-based pharmacokinetic model) was used to estimate the age-dependent differences and inter-individual variability in the biologically effective dose. Physiological parameters, partition coefficients and metabolic parameters for 7 age groups of Japanese population were estimated. Metabolic inhibition in liver was evaluated using an interaction-based PBPK model for the chemical mixture. Significant differences in the calculated biologically effective dose of volatile aromatic hydrocarbons (benzene, toluene, ethylbenzene and xylene) in air were observed between the 18 exposure scenarios. This study demonstrated the feasibility of incorporation of a PBPK model in the risk assessment process to evaluate the age-dependent differences in toxicokinetics and exposure scenarios.
