“Popcorn Lung” (Diacetyl) & Flavoring Chemicals

“Popcorn lung”, medically known as bronchiolitis obliterans, is a rare, irreversible lung disease that scars and narrows the smallest airways. Over time, breathing becomes harder, activity becomes limited, and everyday life can shrink to what the lungs can tolerate.

This disease is strongly associated with workplace inhalation of certain flavoring chemicals, including diacetyl (2,3-butanedione) and related substitutes such as 2,3-pentanedione (acetyl propionyl). In severe cases, workers have become disabled and, in some cases, have died from flavoring-related lung disease.

Where exposure happens

Popcorn lung is not limited to popcorn facilities. Diacetyl and related flavoring chemicals appear in many flavor formulations used across food and beverage production. They have been identified in or used for flavors and products such as bakery items, dairy products, snack foods, and other flavor profiles, and can be present as part of processes involving coffee and beer production.

NIOSH has specifically identified risk in industries such as microwave popcorn, bakery mix, and flavored coffee operations.

What matters in a flavoring-chemical toxic tort case

These cases are built on evidence that connects a workplace environment to irreversible lung damage.

Medical proof

Diagnosis often involves a detailed exposure history plus pulmonary function testing, imaging (X-ray/CT), and sometimes lung biopsy because bronchiolitis obliterans can be difficult to confirm and may be mistaken for other diseases.

Exposure proof

Key details include where and how flavorings were handled, whether flavoring was heated or aerosolized, ventilation conditions, use of respirators or other PPE, and whether the facility conducted air monitoring and implemented controls recommended by OSHA/NIOSH guidance.

Accountability

Safety guidance exists for controlling airborne flavoring exposures; engineering controls, work practices, and respiratory protection where needed. When those safeguards were feasible but ignored or minimized, the risk is no longer an accident, it’s a preventable exposure.

A workplace should not steal someone’s breath

Popcorn lung is a permanent, life-altering diagnosis. When work exposure to diacetyl or other flavoring chemicals is followed by irreversible lung disease or a death from respiratory complications, there should be a serious investigation into what was used, how exposure occurred, and what safeguards were missing.

McEldrew Purtell evaluates flavoring-chemical exposure cases involving catastrophic injury and wrongful death and pursues accountability when preventable exposure changes a life forever.