Diacetyl is a chemical compound that is commonly found in butter and some types of food flavorings. It has a buttery flavor and aroma, making it popular in the food industry, especially in products like popcorn and baked goods. Diacetyl is produced naturally during fermentation and can also be synthesized in laboratories. While diacetyl is generally recognized as safe in small amounts, exposure to high levels can pose health risks, particularly to workers in industries that use it. Prolonged inhalation of diacetyl has been linked to respiratory issues, including a condition known as popcorn lung, which affects the airways.