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. Community Request Diacetyl Center for Research on Ingredient Safety Vaping and Popcorn Lung: What You Need to Know About a Hidden Risk Doctors are warning about a rare but serious lung condition linked to vaping, known as popcorn lung (bronchiolitis obliterans). The disease causes permanent scarring in the lungs' smallest airways, leading to ongoing Harmful Effects of Vaping Vaping: What You Need To Know Community Parents District Home