[Pharmacokinetics of acetaminophen in individuals occupationally exposed to polyvinyl chloride modified with plasticizers].

The aim of this study was to evaluate the health state of a random group of subjects occupationally exposed to polyvinyl chloride. The emphasis was put on the hepatic functional tests in comparison with acetaminophen pharmacokinetics. Forty two males were assigned to two groups: the control group free from occupational exposure and the group exposed to polyvinyl chloride. The latter one was divided into two subgroups according to the length of exposure. The following examinations were carried out in all subjects: subjective and physical examinations, basic laboratory and functional hepatic tests, radioisotope examinations of the liver and spleen, and acetaminophen pharmacokinetics was analysed as well. Acetaminophen was administered intragastrically in a single dose of 1.0 g. Blood was collected within 24 hrs after drug administration. The method of Routh et al. was used for determination of paracetamol concentration. A two-compartment open model for extravascular administration was used for calculation of pharmacokinetic parameters. The results suggest that polyvinyl chloride leads to an accelerated acetaminophen biotransformation, regardless of the length of occupational exposure. There was no correlation between changes in paracetamol metabolism and standard functional hepatic tests. The acetaminophen test can be useful in detecting alterations in the activity of hepatic microsomal enzymes, a symptom of early occupational exposure to chemical compounds with potential hepatoxic properties.