Radium glows. A radium salt in the dark emits a faint blue light, because its radiation excites the nitrogen in the surrounding air. It is warm to the touch, generating heat continuously from its own decay. It appeared to produce energy out of nothing.
Nothing in the history of chemistry has been so immediately or so disastrously popular. Between roughly 1900 and 1930 radium was put into toothpaste, face cream, hair tonic, chocolate, suppositories, wool for babies, and water. The Revigator was a radium-lined crock sold so that a household could leave its drinking water in it overnight. Radithor was radium dissolved in water and sold as a tonic; the industrialist Eben Byers drank it by the case and died in 1932 of radiation-induced necrosis of the jaw and skull, and the resulting publicity did more to end the trade than any regulation.
The most serious harm was occupational. Radium mixed into zinc sulfide paint made watch and instrument dials glow, and from 1917 the United States Radium Corporation and others employed young women to paint them. They were instructed to bring the brush to a point with their lips. Radium is chemically similar to calcium and is deposited in bone. The women developed anaemia, bone fractures and necrosis of the jaw, and a number of them died. Five sued in 1927. Their case, and the medical investigation around it, established the principle of employer liability for occupational disease with delayed onset and produced the first serious standards for handling radioactive material. The women who brought it are known as the Radium Girls.
Radium's medical use in cancer treatment, brachytherapy, was genuine and is the one application that survived; it has since been replaced by cheaper and safer artificial isotopes such as cobalt-60 and iridium-192.