Hundreds of young women working as radium dial painters in the early 20th century were slowly poisoned by the companies that employed them. These 'Radium Girls' painted luminescent watch and clock faces using a technique called lip-pointing—wetted brushes placed in their mouths—while their employers knowingly hid the lethal dangers of radioactive radium despite witnessing horrific deaths and disfigurement among workers. Radium mimics calcium in the human body, causing it to be absorbed into bones where it continuously releases alpha, beta, and gamma radiation that destroys healthy tissue and prevents wound healing.