Flavoring-Related Lung Disease (Bronchiolitis Obliterans)
Bronchiolitis obliterans (BO) is a severe lung disease that has been identified in workers who make microwave popcorn and, more recently in California, in food flavor manufacturing workers. BO is a rare lung disease characterized by fixed airways obstruction and fibrosis of the bronchioles. This disease can cause permanent impairment or death and has been a growing concern among industry, workers and labor advocates, public health officials, and government agencies.
The main symptoms of flavoring-related lung disease are a persistent cough, shortness of breath when using extra energy (such as walking fast or up a slight hill), and wheezing. The symptoms do not go away in the evenings, on weekends, and on vacations. They can start gradually and get worse over time, or they can suddenly be very severe. A worker may have early disease without any symptoms.
Fixed obstructive lung disease such as BO has been associated with exposure to diacetyl, a butter flavoring ingredient. Animal studies suggest that diacetyl is one cause of airway damage that might result in BO, but other flavoring chemicals may have the potential to cause BO or contribute to airway damage.
Workers in flavoring or food production companies that use diacetyl should see a doctor to make sure that their health is not being affected. Companies that use diacetyl or diacetyl-containing flavorings should have a medical surveillance program to monitor their employees’ health to assure they do not develop flavoring-related lung disease. In addition, they should take preventive measures to reduce exposure to diacetyl and other flavoring chemicals. See below for medical guidelines and prevention information.