Modelling dermal pharmacokinetics using in vitro data. Part I. Fluazifop-butyl in the rat.

The pharmacokinetics of the herbicide fluazifop-butyl have been determined in female rats following oral and intravenous dosing, and described by a mathematical model. Penetration of fluazifop-butyl through epidermal membranes has been determined using three different receptor fluids. It is demonstrated how this in vitro absorption data can be used with a pharmacokinetic model derived from oral and i.v. dosing studies to predict plasma concentrations and urinary excretion profiles following dermal dosing. Model predictions are compared with experimental measurements and found to be in good agreement.