[Antipyrine test in petrochemical industry workers exposed to benzene].

Forty petrochemical industry workers occupationally exposed to benzene levels within TLVs (30 mg.m-3) had their hepatic microsomal enzyme function quantitatively assessed by the antipyrine test. The clearance (C1AP) and half life (P1/2) of antipyrine in the saliva were determined. The benzene-exposed workers exhibited increased C1AP and decreased P1/2, as compared to 20 control subjects. The occupational exposure to benzene at the concentrations exceeding 30 mg.m-3 seems to induce the microsomal enzyme function of the liver.