Chemical Carcinogens in Tobacco

Abstract

The association of tobacco usage and cancer has been known for more than five decades. Clinical observations by F.H.Mueller in Cologne in 1939 and by Schairer and Schoeniger in Jena in 1943 were among the first reports to indicate an increased risk for lung cancer among smokers. However, it was not until 1950 that the evidence from case-control studies in the UK and the USA directed attention towards the association of cigarette smoking with lung cancer (Doll and Hill 1950; Levin et al. 1950; Wynder and Graham 1950). In the following 35 years, more than 100 epidemiological reports from at least 15 countries have formed the basis for the conclusions of the US Surgeon General (1982), the Royal College of Physicians (1983), and the International Agency for Research on Cancer (IARC 1986) that cigarette smoking is causally associated with cancer of the lung, larynx, oral cavity, and esophagus, and correlated with cancer of the pancreas, kidney, and urinary bladder, and, possibly also with cancer of the cervix. Cigar and pipe smoking are also causally associated with cancer of the lung, larynx, oral cavity, and esophagus, although the association of these tobacco habits with cancer of the lung and of the larynx is less strong than that of cigarette smoking. Passive smoking gives rise to some risk of cancer (IARC 1986). It has also been concluded that oral use of snuff is carcinogenic to humans (IARC 1985;US Surgeon General 1986).