What to know
Workers exposed to flavorings can develop severe respiratory disease from breathing the harmful chemicals into their lungs. Workers who are affected by flavorings-related disease, or obliterative bronchiolitis, typically experience dry cough, wheezing, and/or shortness of breath during physical exertion. Although not everyone will have symptoms.
Symptom severity
Obliterative bronchiolitis symptoms can range from mild to severe. They typically do not improve when a worker is away from the workplace. Symptoms usually begin gradually and get progressively worse over weeks or months. However, they can also worsen suddenly. Some workers may experience fever, night sweats, and weight loss. Before diagnosing obliterative bronchiolitis, health care providers may question whether symptoms could be related to asthma, chronic bronchitis, emphysema, pneumonia, smoking, or another respiratory condition.
Medical tests
Medical testing may reveal several of the following findings:
Spirometry - A breathing test that measures the ability to move air in and out of the airways and lungs. Spirometry is often abnormal.
Lung volume testing - Measures how much air is in the lungs. Lung volume may show hyperinflation, meaning that air gets trapped in the lungs and causes them to inflate more than normal.
Diffusing capacity of the lungs for carbon monoxide (DLCO) - Another breathing test using a mixture of gas containing carbon monoxide to measure how well oxygen and carbon dioxide move between the lungs and blood. DLCO is generally normal.
Chest x-rays - Images of the lungs. Images are usually normal but may show hyperinflation.
A high-resolution computerized tomography scan (HCRT)- A special imaging test that shows a detailed image of the lung. An HCRT may show a "mosaic pattern" caused by air trapped in some parts of the lungs but not others. It may also show thickened airway walls.
Lung biopsies - A procedure to remove tissue for a microscope examination. A biopsy may show abnormalities consistent with obliterative bronchiolitis.
Medical management
Workers should promptly be referred for further medical evaluation if they experience the following:
- Frequent coughing
- Worsening shortness of breath
- Abnormal lung function with spirometry testing
- Noticeable decline in lung function
It is important for healthcare providers evaluating these workers to know about their work exposures.
To date, most patients have shown little or no response to medical treatment. Affected workers who avoid further exposure to flavoring chemicals generally notice coughing gradually lessens over months to years. However, shortness of breath and abnormalities on lung function tests can be expected to continue.
Disease reporting
NIOSH continues to evaluate new information about risks of occupational exposures to flavorings. We want to hear from workers who have a lung problem that they suspect might be work-related. Workers, labor union representatives, and company management at workplaces with exposures 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 a patient may have obliterative bronchiolitis or other lung disease related to flavoring exposures. Contact NIOSH at:
- CDC-INFO
- TTY 1-888-232-6348
- 1-800-CDC-INFO (1-800-232-4636)
Customer Service Representatives are available in English en Español 8:00am-8:00pm EST, Monday – Friday (Closed Holidays). Cases can be reported to local and state health departments.