The Pop that Must Stop: Butter Flavoring Linked to Respiratory Problems

Sometimes change isn’t always for the better.

When the first exposed risks to diacetyl, a chemical used in butter flavoring, was linked to lung damage in workers at microwave popcorn factories, several manufacturers decided to start using a different ingredient: 2,3-pentanedione (“PD”). However, recent studies have found PD to be just as toxic.

The study, which was published in The American Journal of Pathology, indicates that acute PD exposure has respiratory toxicity which is comparable to diacetyl in laboratory animals. In the study, lab rats were exposed to one of three subgroups for six hours: PD, diacetyl, or filtered air. The rats exposed to PD had airway lining damage in the upper nose comparable to harm caused by in the diacetyl.

This type of damage is believed to be the primary cause of bronchiolitis obliterans, or what has become known as “popcorn worker’s lung.”

Yet, the evidence of PD’s toxicity didn’t end with possible airway lining damage. The researchers also found that PD seemed to alter gene expression in the rats. Exposure to PD activated caspase 3, a protein known to play a role in cell death, in axons of olfactory nerve bundles which are instrumental for our sense of smell. Furthermore, PD exposure was linked to decreased expression of a protein involved in restoring oxygen to tissues in the brain.

Popcorn worker’s lung is a possibly fatal and nonreversible lung disease that comes with symptoms that include shortness of breath and wheezing. Its connection with popcorn has came from many factory workers who developed the disorder after inhaling the diacetyl fumes from the production of bags of microwave popcorn.

Yet, the dangers may even be more far reaching. One man who ate at least two bags of microwave popcorn each night reportedly developed the disease. Earlier this month, a study published in Chemical Reseach in Toxicology revealed evidence that diacetyl may increase beta-amyloid clumping in the brain; the hallmark symbol of Alzheimer’s disease.

With many people working, unprotected, with diacetyl everyday and consumers risking their health using products containing diacetyl in their homes, one would hope that the replacement chemicals manufacturers utilize eliminate potential dangers: not maintain, or worse, intensify them. Yet, as in the case of popcorn factory workers, this does not always seem to be the case.