Acetaldehyde, Ethanal
This is an aldehyde expressed by the chemical formula CH3CHO.
Acetaldehyde is one of the substances in tobacco odor, and is one of the designated malodorous substances based on the Offensive Odor Control Act (olfactory detection concentration is 0.002ppm).
Although its oral toxicity (LD50) in rats, being 1930mg/kg, is not a very high level of direct intake toxicity, but it has been confirmed that the acetaldehyde generated from the consumption and metabolization of alcohol as well as the acetaldehyde generated from smoking is carcinogenic. Acetaldehyde is categorized in group 2B (possibly carcinogenic to humans) by the International Agency for Research on Cancer.
Acetaldehyde is used in large quantities as an industrial raw material, and is one of the Volatile Organic Compounds (VOCs) emitted from adhesives. However, it is known that in nature these VOCs are also widely emitted through metabolization, while ultimately it is oxidized to acetic acid in the body.