1692 Acrylonitrile Acrylonitrile is a chemical compound of cyanide. It is used principally as a monomer in the manufacture of synthetic polymers, especially polyacrylonitrile which comprises acrylic fibers. Acrylic fibers are, among other uses, precursor for well-known carbon-fiber. It is also a component of synthetic rubber and small amounts may be used as a fumigant. It is one ingredient of cigarette. (L583) 107-13-1 7855 C3H3N 53.026550 Colorless liquid. -83.5°C 74.5 mg/mL at 25°C [YALKOWSKY,SH & DANNENFELSER,RM (1992)] Oral (L96) ; inhalation (L96) ; dermal (L96) Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97) Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96) LD50: 148 mg/kg (Dermal, Rat) (T14) LD50: 46 mg/kg (Intraperitoneal, Mouse) (T14) LD50: 35 mg/kg (Subcutaneous, Mouse) (T14) LD50: 93 mg/kg (Oral, Rabbit) (T88) LC50: 425 ppm over 4 hours (Inhalation, Rat) (T14) 204 to 300 milligrams for an adult human (cyanide salts). (T86) 2B, possibly carcinogenic to humans. (L135) Acrylonitrile is used principally as a monomer in the manufacture of synthetic polymers, especially polyacrylonitrile which comprises acrylic fibers. Acrylic fibers are, among other uses, precursor for well-known carbon-fiber. It is also a component of synthetic rubber and small amounts may be used as a fumigant. (L583) Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97) Cyanide poisoning is identified by rapid, deep breathing and shortness of breath, general weakness, giddiness, headaches, vertigo, confusion, convulsions/seizures and eventually loss of consciousness. (L96, L97) Antidotes to cyanide poisoning include hydroxocobalamin and sodium nitrite, which release the cyanide from the cytochrome system, and rhodanase, which is an enzyme occurring naturally in mammals that combines serum cyanide with thiosulfate, producing comparatively harmless thiocyanate. Oxygen therapy can also be administered. (L97) 2009-06-22T16:08:27Z 2014-12-24T20:24:27Z Thiosulfate sulfurtransferase (Q16762) 3-mercaptopyruvate sulfurtransferase (P25325) (L96) C01998 28217 D000181 Acrylonitrile 30 true Thiosulfate sulfurtransferase (Q16762) 3-mercaptopyruvate sulfurtransferase (P25325) (L96) C=CC#N C3H3N InChI=1S/C3H3N/c1-2-3-4/h2H,1H2 InChIKey=NLHHRLWOUZZQLW-UHFFFAOYSA-N 53.0626 53.026549101 Exogenous Liquid CHEMBL445612 7567