Acetylpropionyl

Acetylpropionyl, also known as acetyl propionyl or 2,3-pentanedione, is an organic compound, more specifically a diketone. It is a structural isomer of acetylacetone (2,4-pentanedione).

Uses for acetylpropionyl include:

As a flavoring agent, it is a controversial ingredient in some e-liquid products for use with electronic cigarettes. According to the National Institute for Occupational Safety and Health , inhalation of acetylpropionyl causes respiratory tract epithelial damage and fibrosis to lungs in animal studies. It also causes genetic changes in the animals' brains. Acetylpropionyl was found to cause both intraluminal and intramural fibrotic airway lesions in rats. One study of the composition of 159 different e-liquid products, performed by Farsalinos et al., concluded that the use of acetylpropionyl and diacetyl in E-liquids represents an avoidable risk, and additionally that proper measures should be taken by E-liquid manufacturers and flavoring suppliers to eliminate these hazards from the products.