Popcorn lung disease (bronchiolitis obliterans) is a rare and dangerous ailment that harms workers who inhale the particles of Diacetyl, which is commonly found in butter flavoring. The disease is common in employees of microwave popcorn plants. It is frequently misdiagnosed as bronchitis, emphysema, or asthma.
Breathing tests administered to victims of popcorn lung disease show hyperinflation of the lungs due to trapped air. The tests also reveal thickened airway walls, narrow airways, blocked airways, inability to expand lungs properly, and blurriness on x-rays.