Study: Artificial butter flavor in popcorn can damage lungs

A new study released recently found that exposure to an artificial butter flavor used in popcorn and other foods can damage the noses and airways of mice. The tests showed that diacetyl, a component of artificial butter flavor, can cause a serious condition that can lead to obliterative bronchiolitis or "popcorn lung."

In the tests, conducted by scientists at the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health, mice that inhaled diacetyl vapors for three months developed lymphocytic bronchiolitis—a potential precursor of obliterative bronchiolitis. None of the mice, however, were diagnosed with the more-serious disorder.

Obliterative bronchiolitis is a life-threatening lung disease that has been detected in workers who inhale significant concentrations of the flavoring in microwave popcorn packaging plants. "This is one of the first studies to evaluate the respiratory toxicity of diacetyl at levels relevant to human health. Mice were exposed to diacetyl at concentrations and durations comparable to what may be inhaled at some microwave popcorn packaging plants," said Daniel L. Morgan, Ph.D., head of the Respiratory Toxicology Group at the NIEHS and co-author in a release on the study. It appears online in the journal, Toxicological Sciences.

The authors conclude that these findings suggest that workplace exposure to diacetyl contributes to the development of obliterative bronchiolitis in humans, but said more research is needed.

At the end of last year, four leading popcorn manufacturers—Weaver Popcorn Company, ConAgra Foods (maker of Orville Redenbacher's and ACT II), General Mills (Pop Secret) and American Pop Corn Company (Jolly Time)—announced plans to voluntarily eliminate diacetyl from their products. To address consumer concerns, some companies indicate that their product s are diacetyl-free on the packaging. Still, a number of consumer groups are calling for stronger measures regulating diacetyl.