Clinical research on the hepatotoxicity of toluene

Toluene is metabolized by the liver, and previous research gave contrasting results regarding toluene hepatotoxicity: the present clinical investigation was performed to study the effect of this solvent on hepatic function. 47 subjects exposed to toluene inhalation during working activity were studied. The workers were subjected to medical control and the following tests were performed: bilirubin, GOT, GPT, AP, OCT, GGT, Quick time and protein measurement. Standardized methods were used. All tests gave normal results, with the only exception of GGT, which was above normal (28 mU/ml) in 34% of the cases. In the group of subjects (12) controlled before and after toluene entered in the working operation, mean GGT activity resulted twofold after exposure, without any modification of other tests. These results suggest, in the light of preceding research, that the hepatic damage eventually caused by toluene is mediated through an effect on hepatic microsomal enzymes induction.