Coffee Workers May Be At Risk of Popcorn Lung, Due to Released Diacetyl: CDC

Federal health regulators are warning workers in coffee processing facilities that they may face a risk of developing bronchiolitis obliterans, a severe lung condition that is commonly referred to as “popcorn lung” due to high rates of the condition among microwave popcorn or flavoring factory workers. 

The U.S. Centers for Disease Control and Prevention (CDC) issued the warning to coffer workers about popcorn lung after at least five cases of the condition among individuals that roasted, ground and flavored coffee.

Referred to interchangeably as bronchiolitis obliterans, obliterative bronchiolitis or popcorn lung, the condition is characterized by the scarring and inflammation of small airways that lead to diminished lung capacity and breathing problems. The disease is irreversible and severe cases may require lung transplants or lead to death.

The CDC indicates that research has found roasting coffee beans naturally releases chemicals known as diacetyl and 2,3-pentanedione, both of which have been linked to the development of popcorn lung among microwave popcorn workers. The chemicals belong to a class of volatile organic compounds known as alpha-diketones, and were used to provide butter flavoring to microwave popcorn in prior years.

The warning calls for air sampling for the chemicals, and referred to draft recommendations for exposure standards (PDF) issued by the National Institute for Occupational Safety and Health (NIOSH) in 2011.

“If there are elevated levels of alpha-diketones in workplace air, employees may need to wear the appropriate fit-tested respirators until workplace interventions (e.g. engineering controls, ventilation changes) can be put in place to reduce the air levels (as shown by follow-up air sampling),” the warning notes. “Additionally, a medical surveillance program that includes health questionnaires and breathing tests may be indicated to screen for respiratory symptoms or abnormalities in employees.”

The CDC warned that popcorn lung is often misdiagnosed, highlighting the importance of coffee warning users to be aware of the potential symptoms.

“Sometimes workers with obliterative bronchiolitis are initially misdiagnosed with asthma, chronic bronchitis, emphysema, or pneumonia; or their symptoms are attributed to smoking,” the CDC warned. “It is important to consider the possibility of flavoring chemical-related lung disease in workers who have been exposed to diacetyl or similar flavoring chemicals (such as 2,3-pentanedione) and have respiratory symptoms. In cases of flavoring chemical-related lung disease, respiratory symptoms do not typically improve when the worker goes home at the end of the workday, on weekends, or on vacations. The symptoms often have a gradual onset but can occur suddenly.”

More than 300 popcorn lung lawsuits have been filed in recent years, with most of those coming from employees of popcorn manufacturers. However, some heavy consumers of popcorn have also been diagnosed with the lung disease and have filed lawsuits against companies that manufactured or used the flavoring.

The CDC warning about the potential link between coffee and popcorn lungs does not indicate whether there is any risk to those who roast coffee beans regularly at home.