A simulation study of physiological factors affecting pharmacokinetic behaviour of organic solvent vapours.

At a given external dose of an inhaled chemical the internal dose or the amount absorbed into the body varies depending on pulmonary ventilation and other physiological factors. Such variability is of concern in the development of biological indices of occupational exposure to organic solvent vapours. This paper discusses how physiological factors may influence the pharmacokinetic behaviour of inhaled organic solvent vapours, especially in relation to monitoring of biological exposure. To illustrate the discussion a computer based physiological pharmacokinetic model was used describing quantitatively the influence of body size, body fat content, and sex on the pharmacokinetic behaviour of trichloroethylene. Absorption, distribution, metabolism and excretion of trichloroethylene were found to vary according to the different anatomical features of men and women. Body build (body weight and body fat content) also affected the pharmacokinetic behaviour of this solvent.