Two routes of acrylonitrile metabolism.

Acrylonitrile (AN) is metabolized in two different routes. The minor route of AN metabolism is its conversion to cyanide. In vitro experiments confirmed that this biotransformation proceeds via glycidonitrile (catalyzed by hepatic monooxygenases) and glycolaldehyde cyanohydrin (catalyzed by epoxide hydrase). Cyanohydrin is spontaneously decomposed to cyanide, which is then metabolized in vivo to thiocyanate by rhodanese. A major route of AN-metabolism (more than 2/3), however, proceeds via its conjugation with glutathione catalyzed by glutathione S-alkenetransferases, to N-acetyl-S-(2-cyanoethyl)cysteine as a final product.