1945 - 1955 CE
Health concerns in relation to cigarettes appear and increase as studies link tobacco to diseases

A regional director for the American Cancer Society mentions a correlation between cigarette sales and incidence of lung cancer, while the Mayo Clinic starts warning patients who suffer from vascular disease or arterial injury against cigarette use. In the early 1950's several studies report a link between cigarette smoking and cancer as well as heart disease.

Source: Austin, G. A. et al. (1979). Perspectives on the history of psychoactive substance use. NIDA.