Abstract

A method for the retrospective estimation of the individual respiratory intake was tested. The method is based on system dynamics. Subjects were exposed simultaneously to the poorly metabolising solvent tetrachloroethene (PER, perchloroethylene) and the highly metabolising trichloroethene (TRI) at rest, 30, and 65 watt physical exercise. The time courses of the alveolar concentration (Calv) of both PER and TRI were measured. A retrospective estimation of the individual intake of PER could be carried out up to 400 hours after exposure with 10-20% accuracy, irrespective of the level of exercise. The estimates of the intake of TRI are less accurate. The Calv in the 1-15 hours postexposure permits the estimation of the intake of TRI within a mean error of 25% for most subjects. For men the method may be applied up to 48 hours after exposure within 20% error. For women the intake estimates showed a poor accuracy with the use of Calv beyond the day of exposure.