Experts warn that flavored e cigarettes can cause irreversible lung damage, as seen in a U.S. teenager who developed "popcorn lung"a severe and permanent condition called bronchiolitis obliteransafter secretly vaping for three years. E cigarette, or vaping, product use associated lung injury: a review Pneumonia Springer Nature Link E cigarettes cause lung condition known as EVALI : Revista Pesquisa Fapesp NIH Workshop on E Cigarette, or Vaping, Product Use Associated Lung Injury (EVALI): Developing a Research Agenda NHLBI, NIH