What is Diacetyl?

Diacetyl (dī ă  suh teel) is a greenish yellow liquid that occurs naturally in several foods including butter, milk, cheese, fruits, wine and beer. In industry, it is used to produce butter flavor in certain foods, such as chips, candies, pastries and, most notably, popcorn.   

In recent years, diacetyl has been suspected of causing the lung disease bronchiolitis  obliterans in flavoring and food industry workers with heavy exposure to the chemical, especially in microwave popcorn factories. National Jewish physician Cecile Rose , MD, recently identified a patient whose heavy consumption of butter-flavored microwave popcorn may have caused him to develop bronchiolitis obliterans.   

For more information about diacetyl and lung disease see the U.S. Centers for Disease Control page on  Flavorings-Related Lung Disease.   

This information has been approved by Lisa Maier, MD (Septmeber 2007).