Health Concerns

Acetaldehyde

The greatest exposures to acetaldehyde of the general population may occur via inhalation of contaminated ambient air as well as tobacco smoke. Ingestion and skin contact are other possible routes. Acetaldehyde exists in the ambient air as a by-product of combustion as well as a pollutant caused by certain industrial processes. As noted above, it is also contained in cigarette smoke.

Symptoms of exposure to acetaldehyde include eye, nose and throat irritation; skin burns; dermatitis; conjunctivitis; cough; central nervous system depression; and delayed pulmonary edema (NIOSH). In animals, it is known to produce kidney, reproductive, and teratogenic effects (NIOSH). According to the Hazardous Substance Database, acetaldehyde is less irritating but is a stronger central nervous depressant than formaldehyde.

An IARC study indicates that acetaldehyde is a toxic metabolite formed in the mammalian liver during the oxidation of ethanol. The acetaldehyde is converted to acetyl coenzyme A, which is then oxidized through the citric acid cycle or utilized in various anabolic reactions involved in synthesis of cholesterol, fatty acids, and other tissue constituents (HSDB).

In humans, at low levels of exposure, acetaldehyde is rapidly absorbed and metabolized.

Acetaldehyde has been classified as Class B2: Probable Human Carcinogen by the United States Environmental Protection Agency and as a Group 2B: Possibly  Carcinogenic to humans by the International Agency for Research on Cancer.

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Last Updated: 1/31/03