In order to understand the dangers of Diacetyl we first need to look at where it comes from and how it is getting into our lungs. Diacetyl is a natural chemical compound created by the fermentation of yeast that contributes to the slippery feel of certain types of beer and buttery tasting foods. However, it can also be synthetically produced by food manufacturers as a flavor enhancer or additive. The scary fact is the FDA does not require Diacetyl or its alternative Acetoin, both food additive, to be listed as ingredients in the processed foods we eat and even smoke.
The most popular consumed product Diacetyl has been found in is Microwave Popcorn and e-juice flavorings. Workers in these factories have contracted obstructed lung disease called Popcorn Lung. This is a scarring of the lining of the lungs and obstructs the release of air from the lungs it's only treatable by having a lung transplant. Young non smoking men working in these plants with employment times ranging from 8 months to 10 years have contracted this disease. The FDA is beginning new research into the effects of Diacetyl at the behest of lawmakers who want Diacetyl to be regulated by the FDA.
Electronic cigarettes are battery-powered gadgets which mimic smoking by creating a vapor that simulates smoke. These e-cigarettes generally add a heating element or an atomizer, and a cartridge to hold the e-juice which is a liquid mixture of propylene glycol, vegetable glycerin, nicotine, and flavorings which may contain Diacetyl. Many of the companies that produce the e-liquids have refrained from selling products that contain Diacetyl.