Nitrile compounds, cyanide poisoning from

NIOSH REL (Nitriles) CL 6 mg/mVl5M SAFETY PROFILE Poison by ingestion, intraperitoneal, and intravenous routes. An experimental teratogen. A human skin irritant and allergen. In the preparation of sponge rubber, an azo compound is used that decomposes to form tetramethylsuccinonitrile or TMSN. Rats exposed to a concentration of 90 ppm exhibit their first convulsion after 1.5-2 hours or less. Rats exposed to concentration of 5.5 ppm exhibited their first convulsions in 27-31 hours and were dead in 31-46 hours. Absorbed by skin. The fatal dose in humans is thought to be about 25 mg/kg of body weight. TSN is slowly detoxified by the body. This nitrile is different from other nitriles in that thiosulfate is a poor antidote for intoxication. When heated to decomposition it emits toxic fumes of CN and NOx. See also NITRILES and CYANIDE. 

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