A pesticide's journey through skin: mechanisms and models

Deon van der Merwe, NCSU Center for Cutaneous Toxiciology and Pharmacology

The skin is a major route of chemical absorption into the body for
industrial and agricultural chemicals in the environment. This
presentation describes a physiological-based pharmacokinetic model of
organophosphate dermal absorption through porcine skin. The physical
principles of dermal absorption are discussed. Mathematical constructs
of biological structures and physiological processes, which determine
the kinetics of dermal absorption, are used to describe the absorption
flux/time curves of organophosphates applied to the skin surface. Model
predictions are compared to observed absorption data. The use of such
models to test hypotheses and gain understanding of the underlying
processes of dermal absorption is also demonstrated. The benefits and
limitations of using this type of mechanistic model in toxicology are
discussed - emphasizing its potential in relation to the emerging field
of systems biology.