Bronchiolitis obliterans is a serious lung disease that is commonly known as “popcorn lung.” The disease got its nickname for the five microwave popcorn plant workers that developed the disease in 2000 after long-term exposure to diacetyl, a chemical used as a flavoring that mimics the creamy taste of butter.
Diacetyl is a naturally occurring chemical in the coffee bean roasting process, and is often added to foods and drinks that are enhanced by a buttery flavor, such as cooking oil, cooking sprays, baking mixes, beer and flavored coffee. It has also been found in e-cigarette liquids, which raises concerns about the potential lung damage when the chemical is heated before it is inhaled.
According to the U.S. Food and Drug Administration (FDA), diacetyl is safe when eaten in trace amounts, but scientists with National Institute of Occupational Health and Safety (NIOSH), the research arm of the U.S. Centers for Disease Control and Prevention (CDC), have declared the chemical to be potentially harmful if inhaled, now that it has been linked to popcorn lung. Additionally, the stomach processes the chemical very differently than the lungs.
Bronchiolitis obliterans, a disease in which the smallest airways in the lungs form scar tissue that diminishes breathing, is only treatable by lung transplant. But even with a transplant, survival isn’t guaranteed.
According to a study in 2003, lung transplant recipients are still at risk for developing the disease all over again, due to chronic allograft rejection. Once chronic allograft rejection begins, the small airways progressively narrow, leading to fatal respiratory failure within five years after onset.