In one of the most famous scenes in 'The Wizard of Oz' (1939), Dorothy and her friends fall asleep in a poppy field and are woken up by a gentle blanket of falling snow. In the 1930s, however, 'movie magic' often relied on dangerous materials. The 'snow' used in that scene was actually 100% industrial-grade chrysotile asbestos. At the time, asbestos was a common substitute for snowflakes because it was fireproof and looked realistic under studio lights. The actors, including Judy Garland, were essentially showered in carcinogenic fibers for hours of filming. This wasn't an isolated incident; asbestos 'snow' was sold commercially for home holiday decorations and used in several other Hollywood classics like 'White Christmas' and 'Holiday Inn.' It wasn't until after World War II that the health risks of asbestos became widely understood and the practice was halted.