Some effects of trichloroethylene on mouse lungs and livers.

Repeated administration of trichloroethylene (TCE) to mice by either i.p. injection or by inhalation increased the activity of hepatic microsomal NADPH cytochrome-c reductase. The NADPH cytochrome c reductase activity in microsomes isolated from lungs of animals treated with TCE by inhalation was decreased relative to controls (untreated animals). TCE inhalation was associated with pathologic changes in lungs, but not in livers of the treated animals. The duration of exposure is probably an important factor however, since animals exposed for only 1 hr per day exhibited neither pathologic changes in the lungs nor an alteration of enzyme activity. These findings indicate that inhalation of TCE, without prior treatment with inducers, can enhance activity of the hepatic mixed function oxidase system. The reduced activity of the pulmonary mixed function oxidase system in animals that inhaled TCE may reflect injury to the lungs.