Acetaldehyde is a substance that is produced in the human body during metabolic processes, for example when the body breaks down alcohol.  The taste of acetaldehyde is described as fresh with a fruity but sometimes musty odour.

Acetaldehyde is widely used in the production of other industrial chemical substances. It is used as a solvent in the rubber, tanning and paper industries, and as a preservative for fruit and fish. Sometimes it is also used as a flavouring agent.

Sources

Acetaldehyde is ubiquitous in the ambient environment.  It is an intermediate product of higher plant respiration and formed as a product of incomplete wood combustion in fireplaces and woodstoves, coffee roasting, burning of tobacco, vehicle exhaust fumes, and coal refining and waste processing.  Hence, many individuals are exposed to acetaldehyde by breathing ambient air.  It should be noted that residential fireplaces and woodstoves are the two highest sources of emissions, followed by various industrial emissions.

Health Effects

Acetaldehyde is mainly used as an intermediate in the synthesis of other chemicals.  It is ubiquitous in the environment and may be formed in the body from the breakdown of ethanol.  Acute (short-term) exposure to acetaldehyde results in effects including irritation of the eyes, skin, and respiratory tract.  Symptoms of chronic (long-term) intoxication of acetaldehyde resemble those of alcoholism. Acetaldehyde is considered a probable human carcinogen (Group B2) based on inadequate human cancer studies and animal studies that have shown nasal tumors in rats and laryngeal tumors in hamsters.