INDIVIDUAL-VALUES OF EXCRETION OF BENZO[A]PYRENE METABOLITES AND SUSCEPTIBILITY TO ITS CARCINOGENIC EFFECT IN RATS

In white outbred LIO rats exposed to multiple intraperitoneal (i.p.) d oses (10 mg/kg) of benzo[a]pyrene (BP) in the form of a water-lipid em ulsion, individual peculiarities of the excretion of its metabolites, BP-7,8-diol and 3-hydroxy-BP (3-OH-BP) in urine and feces were detecte d and compared with the carcinogenic effect. Parameters of BP metaboli te excretion differed from those found in our previous experiments wit h rats exposed to single high i.p. doses of BP (100 and 200 mg/kg), di ssolved in sunflower oil [11,12]. In comparison with our previous obse rvation, in the present study, the carcinogenic effect was considerabl y weaker (5/22 versus 10/19). The rats that developed tumours of inter nal tissues (four peritoneal malignant histiocytomas and one lung lymp hosarcoma), excreted higher quantities of BP-7,8-diol in the urine tha n other rats. The possible implication of monitoring excretion of BP m etabolites for predicting individual susceptibility to its carcinogeni c effect is discussed.