Biological monitoring of controlled toluene exposure.
Widespread exposure to toluene occurs in the printing, painting, automotive, shoemaking, and speaker-manufacturing industries.
The relationship between air concentrations and the absorbed dose is confounded by dermal exposure, personal protective devices, movement throughout the workplace. and interindividual differences in toluene uptake and elimination.
To determine the best biological indicator of exposure we examined the blood and alveolar breath concentrations of toluene as well as the urinary excretion rates of hippuric acid and of O-m-and p-cresols from 33 controlled human inhalation exposures to 50 ppm for 2 h. Results : Among the metabolites, o-cresol was least influenced by background contributions, whereas the p-cresol and hippuric acid rates were obscured by endogenous and dietary sources.
Toluene levels in alveolar breath proved to be the most accurate and noninvasive indicator of the absorbed dose.
A physiologic model described blood and breath data using four measured anthropometric parameters and the fit values of extrahepatic metabolism and adipose-tissue blood flow.
After breathing rate and extrahepatic metabolism had been set to conservative (protective) values (the 97.5th and 2.5th percentiles, respectively) the model predicted that pre-final-shift breath levels of <=10 mumol/m3 and post-final-shift levels of <=150 mumol/m3 corresponded to average workplace exposure levels of <=50 ppm toluene. (...)
Mots-clés Pascal : Toluène, Solvant organique, Exposition professionnelle, Médecine travail, Surveillance biologique, Marqueur biologique, Liquide biologique, Urine, Sang, Alvéolaire, Teneur air, Etude comparative, Modèle PBPK, Modélisation, Homme
Mots-clés Pascal anglais : Toluene, Organic solvent, Occupational exposure, Occupational medicine, Biological monitoring, Biological marker, Biological fluid, Urine, Blood, Foam(plastics), Air content, Comparative study, Physiologically based pharmacokinetic model, Modeling, Human
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0032405
Code Inist : 002B03L04. Création : 31/05/1999.