Researchers have uncovered a potential link between diacetyl, the flavoring ingredient that produces the buttery flavor of microwave popcorn, and Alzheimer’s disease. Diacetyl already has been associated with potentially fatal lung disease.
Occupational exposure to diacetyl among workers in microwave popcorn and food-flavoring factories has been linked with respiratory problems and debilitating lung disease. This new study found evidence that diacetyl could intensify the damaging effects of an abnormal brain protein linked to Alzheimer’s disease.
Robert Vince and colleagues Swati More and Ashish Vartak realized that diacetyl has an architecture similar to a substance that makes beta-amyloid proteins clump together in the brain, with clumping being a hallmark of Alzheimer’s disease. The studied whether diacetyl increased the level of beta-amyloid clumping and found that it did.
At real-world occupational exposure levels, diacetyl also enhanced beta-amyloid’s toxic effects on nerve cells growing in the laboratory. Other lab experiments showed that diacetyl easily penetrated the so-called “blood-brain barrier,” which keeps many harmful substances from entering the brain. DA also stopped a protective protein called glyoxalase I from safeguarding nerve cells.
“In light of the chronic exposure of industry workers to diacetyl, this study raises the troubling possibility of long-term neurological toxicity mediated by diacetyl,” explained the researchers.
In recent years, OSHA has recognized the potential hazards of occupational diacetyl exposure and has expressed intent to introduce a diacetyl standard. In 2009, Secretary of Labor Hilda Solis said, “I am alarmed that workers exposed to food flavorings containing diacetyl may continue to be at risk of developing a potentially fatal lung disease … These deaths are preventable, and it is imperative that the Labor Department move quickly to address exposure to food flavorings containing diacetyl.”
The study appears in the ACS journal Chemical Research in Toxicology. The authors acknowledge funding from the Center for Drug Design (CDD) research endowment funds at the University of Minnesota, Minneapolis.