Flavoring Symptoms and Medical Monitoring

doctor examining patient

Photo by NIOSH

Workers who are affected flavorings-related lung disease, or obliterative bronchiolitis, mainly experience these symptoms:

  • Cough (usually without phlegm)
  • Wheezing
  • Shortness of breath on exertion

The severity of symptoms can range from mild cough to severe. These symptoms typically do not improve when a worker is away from the workplace. Symptoms usually begin gradually. However, severe symptoms can occur suddenly. Some workers may experience fever, night sweats, and weight loss. Before arriving at a final diagnosis, doctors of affected workers may initially confuse the symptoms with asthma, chronic bronchitis, emphysema, pneumonia, or smoking.

Medical Tests

Medical testing may reveal several of the following findings:

  • A breathing test called spirometry often shows fixed airways obstruction. This means quickly exhaling air completely out of the lungs with no improvement when given asthma medications. Spirometry sometimes shows a restrictive pattern (i.e., decreased ability to fully expand the lungs).
  • Lung volume testing is a test that measures how much air is in the lungs. This test may show hyperinflation, which is when air gets trapped in the lungs and causes them to inflate more than normal.
  • Diffusing capacity of the lung (DLCO), another type of breathing test, is generally normal, especially early in the disease.
  • Chest x-rays show images of the lungs. Results are usually normal but may show hyperinflation.
  • A high-resolution computerized tomography (HRCT) scan is a special computerized tomography (CT) scan that shows a more detailed image of the lung. When performing a HRCT, the patient fully inhales then fully exhales. This may reveal air that is trapped when exhaling, haziness, and thickened airway walls.
  • Lung biopsies are procedures that remove a small amount of tissue from the lung to help identify disease. Biopsies may reveal evidence of severe narrowing or complete airway obstruction. This is called constrictive obliterative bronchiolitis.

Medical Management

Workers should promptly be referred for further medical evaluation if they experience:

  • Frequent coughing
  • Frequent shortness of breath when exhaling
  • Frequent eye, nose, throat, or skin irritation
  • Abnormal lung function on spirometry testing
  • Accelerated decline in lung function

Healthcare providers should advise workers about medical conditions that may be caused or aggravated by work exposures. Additionally, healthcare providers should provide appropriate recommendations for evaluation and treatment.

To date, most patients have shown little or no response to medical treatment. Affected workers generally notice a gradual reduction of cough years after they are no longer exposed to flavoring chemicals. However, abnormalities on lung function tests and shortness of breath when exhaling continue.

It is possible that workers with pre-existing asthma may experience worsening of their asthma due to the irritant properties of flavoring chemicals.

Disease Reporting

NIOSH is continuing to evaluate new information about the risk of obliterative bronchiolitis from occupational exposures to flavorings. NIOSH wants to hear from workers who have a lung problem that they suspect might be related to their work with flavorings. Workers, labor union representatives, and company management at workplaces where workers may be exposed to flavoring-related chemicals can request a NIOSH health hazard evaluation (HHE) of their facility.

NIOSH also wants to hear from healthcare providers who suspect flavorings-induced occupational or non-occupational obliterative bronchiolitis in a patient. NIOSH can be contacted to inquire about or provide information regarding lung disease that may be related to exposures to flavoring chemicals. Cases can also be reported to local and state public health departments.