Teenager Diagnosed Of 'Popcorn Lung'; Doctors Suspect Vaping Habit CodeBlue 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 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 Popcorn lung' may have brought teen close to death after vaping for months Stout Middle School The Lessons of Popcorn Lung: Inhale With Caution