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 the 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.