3-Hydroxypropionic acid is a building block in the synthesis of a variety of compounds with industrial applications, including acrylic acid, acrylamide, and 1,3-propanediol. Accumulation of 3-hydroxypropionic acid is also used as a biomarker of defects in propionic acid and branched-chain amino acid catabolism in patients with methylmalonic acidemia or propionic acidemia.