Does Vaping Cause Popcorn Lung? What the Science Shows

Popcorn lung, or bronchiolitis obliterans, describes scarring that blocks the small airways in the lungs. The condition was first identified among microwave popcorn workers exposed to high levels of diacetyl, a butter-flavored chemical. This article explains what popcorn lung is, how diacetyl and other flavoring chemicals relate to it, which products have contained diacetyl, and what the available scientific evidence says about vaping and risk. Where research is limited or uncertain, the information below notes that uncertainty clearly.