INTRODUCTION AND BACKGROUND Historically the field of chemical carcinogenesis may have begun with Hill in 1761@ who correlated the increased incidence of nasal polyps and nasal cancer to the prolonged use of snuff (Redmond@ 1970). In 1775 Percival Pott noted that the scrotal skin cancer so often found in chimney sweeps@ was directly related to the exposure of these workers to large amounts of coal tar and soot (Pott@ 1963). Subsequently@ the importance of occupational cancer prevention was recognized three years after Pott's observations: The Danish chimney sweeper's guild urged its members to take daily baths (Clemmesen@ 1951). The apparent success of this measure was recognized 100 years later by Butlin who concluded that the lower incidence of scrotal cancer among Northern European chimney sweeps@ as compared to the incidence of this cancer in English chimney sweeps@ was related to the better personal hygiene and protective clothing of the former group (Butlin@ 1892). Since then there have been many correlations between the occurrence of human cancer and exposure to certain chemicals or chemical mixtures in specific industrial@ medical@ or societal situations. Widespread public concern about chemical carcinogens is relatively recent. Extensive studies in cancer epidemiology imply that environmental factors are involved in the causation of many important cancers in man (Doll@ 1980; Higginson@ 1969; Higginson@ 1978). Epidemiological studies based on geographic variations in cancer incidence have indicated that many human cancers are caused@ mediated or modified by environmental factors such as ionizing and ultraviolet radiation@ methylcholanthrene and benzo(a)pyrene (Wynder and Maruchi@ 1972; Higginson and Muir@ 1973; Cairns@ 1975). Recent observations on the incidence@ type and geographic distribution of cancer mortalities (for specific histological types of cancer and sites of neoplasia) vary widely from country to country and in some cases between localities in a given country (Doll@ I980; Higginson@ 1969; Mason@ et al.@ 1975; Waterhouse@ et al.@ 1976). Evidence of subtle environmental influences on cancer induction in adults who have moved from their native country is shown by a cancer mortality rate characteristic of the inhabitants of their new country (Miller@ 1977; Haenzel and Kurinhara@ 1968; Kmet@ 1970; Miller@ 1977).
API PUBL 31-30263-1983 history
1983API PUBL 31-30263-1983 IN VITRO DETERMINATION OF CHEMICAL COCARCINOGENESIS IN BALB/c 3T3-A31SF CELL CULTURES