The Wizard of OZ Snow was Asbestos

The poppy field scene in "The Wizard of Oz" became infamous over the years after viewers learned that the fake snow in the scene was 100% asbestos. Chrysotile, which is white asbestos, was also used for this scene. Despite the fact that asbestos' health risks were already known at the time, film sets started using one of the purest forms of asbestos on film stages because it was fireproof and looked close enough to snow that it could fool the audience.