Lungs After Smoking: Understanding Popcorn Lung from Vaping Vaping, Diacetyl, and Popcorn Lung: Is the Threat Real? Vaping360 Popcorn lung. Vaping lung injury. Let's stop confusing the two. Popcorn lung is the lazy name for bronchiolitis obliteransa disease of the small airways, not the alveoli. It got its name from Popcorn Lung: The Deadly Secret in Your Vape! Did you know that the sweet, tempting flavor in your e liquid could be hiding a chemical called Diacetyl? This chemical, which tastes