https://mensch-und-atom.org/index.php/en/focus2/radiation/item/140-radium-girls-abused-innocence#sigProId32ed5e5a93
Radium Girls was the name given to the women who worked in watch factories in the East Coast around 1917, applying radioactive luminous paint called Undark so the watch numbers and hands would glow in the dark. Even though the dangers of radiation were already well known by that time, they used to wet their paintbrushes with their lips to give them a fine point. The young women paid for this with their health. More and more of them died until four terminally ill former workers eventually sued the company US Radium. Although hey had been defamed by the opposing attorneys as hysterical women, they were eventually satisfied with a modest settlement. A few years later all of them were dead. Above their graves, the radiation is still measurable to this day. Although the operating companies have refused to acknowledge any responsibility, they gradually introduced safety precautions in their facilities. In 1941, after years of studies, the first tolerance levels for radioactive exposure of dial painters were established. They are lower than today's tolerance levels set for workers in nuclear power plants. The Radium Girls were scientifically examined through a broadly funded research programme until the early 1990s. Although the research programme was discontinued in 1993, a final report is still pending.
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