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 LD50 was found to be 940 mg/kg body weight, which is about three times the LD50 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 monooxygenase 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 14CO2-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.