Many chemotherapeutic agents introduced for use in humans are carcinogenic in laboratory animals (Conklin et al. 1965; Shimkin et al. 1966; Griswold et al. 1968; Harris 1976). However, initially their beneficial effect in disseminated cancer was of such short duration that the inevitable death of the patient from his primary disease precluded any clinical manifestation of the carcinogenic potential. During the last decade, chemotherapy has radically changed the outlook for many patients with cancer. Combinations of drugs, administered as the primary treatment, have resulted in high rates of...

Trichloroethylene (TRI), administered orally at high doses for 18 months has been shown to increase the incidence of hepatocellular carcinoma in B6C3F 1 mice but not Osborne-Mendel rats (NCI, 1976). The interpretation of these studies has been confounded due to the presence of epoxide stabilizers in the TRI. However more recent studies have demonstrated that pure TRI also causes hepatocellular carcinoma in B6C3F mice (NTP, 1983) and Aldedey Park (Swiss) mice (Elcombe 1 and Pratt, unpublished data). Furthermore, no increase in the incidence of hepatocellular carcinoma was observed in Fisher...

The first oral contraceptive became available in 1960 and since then these sub stances, which have been used by millions of women, have probably been the most widely studied group of drugs in medical history (Drill, 1966, 1977). Part of the evaluation oCoral contraceptives has involved their effect on the reproductive organs of women, with particular attention directed to evaluation of a possible carcinogenic effect of these steroids. To the extent that cancer of the reproductive organs is a common finding in women, the endogenous female sex hormones have been implicated in the occur rence of...

Nervous system is in the most cases a likely target for the untoward effects of chemicals. The harmful consequences affect primarily the individual but may also considerably strain the whole society. The consumption of ethanol is a glaring example (National Institute on Alcohol Abuse and Alcoholism 1978). As ethanol, many organic liquids have similar immediate effects on the nervous system. The rapidity of the response suggests the involvement of the neuronal communication. The nervous system is also vulnerable to the depletion of oxygen, another common cause for the rapid deterioration of...