Biological monitoring: the role of toxicokinetics and physiologically based pharmacokinetic modeling.

Abstract

This short review outlines the contribution of modeling techniques, particularly physiologically based pharmacokinetic (PBPK) modeling, in promulgating biological monitoring as a practical tool for the occupational health professional. The impact of modeling techniques is discussed in helping to establish the relevant biomarkers to measure, the appropriate time of sampling, and the relationship between atmospheric exposure limits and concentration of biological analyte. Of particular interest is the use of "population" PBPK techniques. These can explore the influence of physiological differences between workers or of particular susceptible subgroups (e.g., pregnant women, breast-feeding mothers, and infants) on the relationship between atmospheric exposure levels and biomarker concentration. Such techniques will become more widely used as biological monitoring guidance values (e.g., biological exposure indices, biological tolerance values) are increasingly established by various international professional and regulatory bodies.