the market. In the United States, the experience of the so-called Radium Girls, where thousands of radium-dial painters contracted oral cancers, popularized the warnings of occupational health associated with radiation hazards. Robley D. Evans, at MIT, developed the first standard for permissible body burden of radium, a key step in the establishment of nuclear medicine as a field of study. With the development of nuclear reactors and nuclear weapons in the 1940s, heightened scientific attention was given to the study of all manner of radiation effects. Notes References Radiation health effects