FIGURE 24-8 Chemical carcinogenesis by tobacco smoke. Cigarette smoking provides a clear example of a deadly form of chemical carcinogenesis. The rates of lung cancer follow the rates of smoking, with about a 30-year lag. Women began to smoke in large numbers starting in the 1960s, and starting in the 1990s, lung cancer passed breast cancer as the leading cause of women’s cancer deaths. At the same time, a gradual decrease in smoking rates among men starting in the 1960s has been reflected in a decrease in their lung cancer rate.

[Data from the American Cancer Society.]