Workers at popcorn production plants may be exposed to vapors that may cause lung disease, according to a study.

Researchers, whose study appears in the August issue of Chest, say severe airway obstruction and irreversible damage to the lungs has been reported in microwave popcorn production workers in the past. The researchers write that inhalation of vapors from flavoring agents may have caused the severe lung disease.

The current study found no link between popcorn-flavoring vapors and airway obstruction. But these new findings indicate that high exposure to popcorn flavoring agents is significantly associated with airway inflammation in popcorn production workers, says researcher Muge Akpinar-Elci, MD, in a news release.

Read WebMD's "Babies’ Wheezing, Local Traffic May Be Linked"

Exposure to Flavoring Agents' Vapor

The researchers analyzed coughed-up mucus from workers at a popcorn plant and showed that high exposure to vapors from flavoring agents was linked to higher levels of inflammatory cells.

This further analysis supported the evidence that popcorn production workers are prone to significant occupational hazards through exposure to flavoring agents, they write.

The study was done at a microwave-popcorn plant that produced both flavored microwave popcorn and unflavored kernel popcorn.

In the study, a total of 140 workers were selected to participate. Fifty-nine had jobs that exposed them directly to the popcorn-flavoring vapors; 22 held positions with low exposure.

Participants were asked to answer questions about breathing, cough symptoms, and smoking history. The researchers analyzed sputum samples and tests of lung functions on the participants.

The researchers show that mucus from nonsmoking popcorn plant workers had significantly higher levels of inflammatory cells than a group of healthy nonsmokers.

The researchers could not show a relationship between inflammation and airway obstruction on a test of lung function.

An unexpected finding the study was the lack of a significant relationship between inflammatory markers in mucus and airway obstruction, the researchers write. They add that the small numbers of participants in their study may have been insufficient to show a relationship between inflammation and airway obstruction.

Popcorn itself is not harmful. Americans consume more than 17 billion quarts of popped corn a year, according to a 2001 article from USA Weekend. That comes out to about 68 quarts apiece. Popcorn is low fat and contains less sodium than potato chips and pretzels, according to the U.S. Department of Health and Nutrition.

Read WebMD's 'Microwave Popcorn: No Consumer Risk Known"

By Patti Connor, reviewed by Brunilda Nazario, MD

SOURCES: Akpinar-Elci, M. Chest, August 2005; vol 128: pp 991-997. News release, Chest.