Does Diacetyl In Vaping Cause Popcorn Lung? SMOKO E Cigarettes Butter scented chemical linked to "popcorn lung" (bronchiolitis obliterans) discovered in vape juices, and is the most common flavoring chemical in e liquids. In the new study, the chemical, together with another similar one, Vaping Looks Harmless Until It Isnt, , Many teenagers think vaping is safer than smoking., But the damage can be just as serious., , Most vapes contain extremely high nicotine levels., JUUL electronic cigarette products linked to cellular damage UCR News UC Riverside