Bronchiolitis obliterans, also known as popcorn lung and constrictive bronchiolitis, is a disease that results in obstruction of the smallest airways of the lungs (bronchioles) due to inflammation. Symptoms include a dry cough, shortness of breath, wheezing and feeling tired. These symptoms generally get worse over weeks to months. Causes include breathing in toxic fumes, respiratory infections, connective tissue disorder or complications following a bone marrow or heart-lung transplant. Symptoms may not occur until two to eight weeks following toxic exposure or infection. The underlying mechanism involves inflammation that results in scar tissue formation. While the disease is not reversible, treatments can slow further worsening. 

There are many industrial inhalants that are known to cause various types of bronchiolitis, including bronchiolitis obliterans. Industrial workers who have presented with bronchiolitis:

  • nylon-flock workers
  • workers who spray prints onto textiles with polyamide-amine dyes
  • battery workers who are exposed to thionyl chloride fumes
  • workers at plants that use or manufacture flavourings, e.g. diacetyl butter-like flavouring

Indeed the disease got the name “Popcorn lung” gas workers in a popcorn factory in the 1980s became sick after breathing in harmful chemicals. While the diacetyl generally considered safe to eat, it’s dangerous when inhaled.

If there is a risk of popcorn lung at your workplace, ensure appropriate engineering controls such as exhaust hoods and closed systems are in place. Moreover, use suitable personal protective equipment (PPE) as well. It is important to ensure a safe system of work, monitoring of potentially affected workers, and worker education/ training.

See your doctor if you have been exposed to harmful chemicals. They can refer you to a specialist or figure out the best treatment plan for you.