Effects of phenolic smoke condensates and their components on hepatic drug metabolizing systems

Treatment of food with wood smoke is a long-established method of preservation and flavouring food. Recently, hardwood smoke condensates, purified of polycyclic hydrocarbons, have become of importance for direct flavouring of sausage-meat. The acute toxicity of the purified phenolic fraction in mice after intraperitoneal administration was therefore investigated. The LD 50 was found to be 940 mg/kg body weight, which is about three times the LD 50 of phenol (about 300 mg/kg). Only high concentrations of phenols or smoke condensate fractions are able to damage cytochrome P-450 by conversion to cytochrome P-420, whereas lower concentrations exhibit inhibitory effects on mono-oxygenase activity. Inductive properties of the phenolic fractions could not be demonstrated. Concentrations in vivo of free phenolic compounds do not reach inhibitory levels, since the hexobarbital-induced sleeping-time and 14CO 2-exhalation after administration of p-[methoxy- 14C] acetanilide are not altered. It is concluded that the phenolic compound intake with food regularly treated with smoke condensate fractions is below a toxicologically relevant level.