Dial painters were told to lip-point radium brushes to a fine tip

In the 1910s and '20s, young women at U.S. Radium Corporation hand-painted glowing watch dials, shaping their brushes to a point with their lips as supervisors instructed, while those same supervisors wore lead aprons and used tongs. Many later developed radiation poisoning and bone cancer. Five dying workers sued in 1927, helping establish US occupational-disease law.

— Kate Moore, The Radium Girls: The Dark Story of America's Shining Women — Sourcebooks, 2016
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