hydroxyethanoic

Hydroxyethanoic acid, also known as glycolic acid or hydroxyacetic acid, is the simplest example of an alpha-hydroxy carboxylic acid. Its chemical formula is C2H4O3, and its structure consists of a carboxyl group (COOH) adjacent to a hydroxyl-bearing carbon (HO-CH2-).

In nature and industry, glycolic acid appears as a metabolic intermediate in plants and animals and is produced industrially by chemical routes. Industrial production typically involves the oxidation of precursors such as ethylene glycol or the hydrolysis of glycolonitrile, which itself can be derived from formaldehyde and hydrogen cyanide. Glycolic acid is highly soluble in water and is hygroscopic, forming clear solutions and sometimes crystallizing under certain conditions.

Uses for glycolic acid are diverse but it is best known for its role in cosmetics and dermatology. As an alpha-hydroxy acid, it is employed in exfoliating skin products and chemical peels to promote desquamation and skin turnover. It is also used as a chemical intermediate in the synthesis of esters and other derivatives, and finds applications in certain cleansing and industrial formulations due to its acidity and solubility properties. In formulated products, the concentration and pH are carefully controlled to balance effectiveness with safety and skin tolerance.

Safety and handling considerations reflect its acidic and irritant nature. Glycolic acid can irritate eyes, skin, and mucous membranes, especially at higher concentrations. It is typically used in cosmetic products at low concentrations (often around 5–10%), with protective measures in place for industrial handling. Proper storage in a cool, dry place and away from strong bases and oxidizers is advised.