Percivall Pott becomes the first scientist to demonstrate that a cancer may be caused by an environmental carcinogen when, in 1775, the English surgeon finds an association between exposure to soot and a high incidence of scrotal cancer (later found to be squamous cell carcinoma) in chimney sweeps.

This is the first occupational link to cancer, and the early investigations cry post, one of the founders of orthopedy, contribute to the science of epidemiology and lead to the Chimney Sweeper's Act of 1788.