What is Popcorn Lung? Popcorn Lung is a serious, permanent lung disease caused by inhaling harmful chemicals like diacetyl, sometimes found in flavored vapes. Tips for Parents & Caregivers: Talk The Promise of Vaping and the Rise of Juul The New Yorker Vaping Safety, Smoking, Dangers, Pros, Cons, Debate, E cigarettes, & Tobacco Britannica Popcorn lung: What is it, and who is at risk? Harvard Health