[ Acetaldehyde, ethanal ]

An aldehyde, also known as ethanal (not to be confused with ethanol), that occurs naturally in the environment. Human exposure comes from air, smoke, ground water, some plant-based foods, and from alcohol consumption.

Acetaldehyde may cause irritation of the skin, mucous membranes, and respiratory tract. It is also known to cause muscle deformation, DNA damage and cancer.

Food sources of acetaldehyde include coffee, bread and fruit. It is one of the byproducts of alcohol metabolism due to oxidation of ethanol by the liver enzyme alcohol dehydrogenase. It is considered a contributing factor to hangovers.

Acetaldehyde is broken down in the liver into acetic acid by acetaldehyde dehydrogenase.