A Kernel of Truth: Diacetyl, Popcorn Lung and E Liquids Dinner Lady What's in an E Cigarette? American Lung Association Popcorn lung: What is it, and who is at risk? Harvard Health Legal Aussie vapes contain banned chemicals, testing reveals The Australian Diacetyl: The Hidden Chemical That Changed Vaping and Food Safety Forever SMOKO E Cigarettes It's official. Flavored e cigarettes cause permanent lung damage. And doctors are already seeing it happen. In the United States, a teenager developed something called popcorn lung after secretly vaping for three years.