Inhalation toxicity hydrogen cyanide

Levin BG, Braun E, Paabo M, Harris RH, and Navarro M (1992) Reduction of Hydrogen Cyanide Concentrations and Acute Inhalation Toxicity from Flexible Polyurethane Foam Combustion Products by the Addition of Copper Compounds. Part IV. Effects of Combustion Conditions and Scaling on the Generation of Hydrogen Cyanide and Toxicity from Flexible Polyurethane Foam with and without Copper Compounds. NISTIR 4989. Gaithersburg, MD National Institute of Standards and Technology. 

Acetone cyanohydrin is a highly poisonous componnd. Although the acute toxicity is lower than that associated with hydrogen cyanide, the toxic effects are similar to those of the latter compound. The toxic rontes are inhalation, ingestion, and skin contact. 

Cyanohydrins are highly toxic by inhalation or ingestion, and moderately toxic through skin absorption (21). AH a-hydroxy nitriles are potential sources of hydrogen cyanide or cyanides and must be handled with considerable caution. Contact with the skin and inhalation should be rigorously avoided. Special protective clothing should be worn and any exposure should be avoided (18,20). The area should be adequately ventilated. Immediate medical attention is essential in case of cyanohydrin poisoning. 

Hydrogen selenide, a possible by-product, is very toxic, being comparable with hydrogen cyanide. Its accidental inhalation in small amounts may produce a sore throat. 

In the section that follows, data needs are identified for cyanide forms for which toxicity data were available and were, therefore, summarized in Section 2.2. These forms include primarily sodium cyanide, potassium cyanide, and hydrogen cyanide. As seen from Figure 2-6, information is available regarding death, systemic effects of acute exposure, and neurological effects in humans after inhalation, oral, and dermal exposure to cyanide. In addition, information is available regarding chronic systemic effects in humans after inhalation and oral exposure. 

Potassium cyanide (KCN) is a white crystalline substance with a slight odor of bitter almonds. It is produced when hydrogen cyanide is absorbed in potassium hydroxide. It is used to extract gold and silver from their ores, in electroplating computer boards, and as an insecticide. Potassium cyanide is very toxic to the skin or when ingested or inhaled, and it is used as a source of cyanide (CN) gas in gas chambers. 

Hydrogen cyanide has recently been recognized in significant concentrations in some fires, as a combustion product of wool, silk, and many synthetic polymers it may play a role in toxicity and deaths ftom smoke inhalation." ... 

Hydrogen cyanide is extremely toxic hy ingestion, inhalation, skin absorption, and all routes of exposure. An oral dose of 50 mg could be lethal to humans (Patnaik, P. 1999. A Comprehensive Guide to the Hazardous Properties of Chemical Substances, 2nd ed.. New York John Wiley). Symptoms from acute poisoning include labored breathing, shortness of breath, paralysis, unconsciousness, and respiratory failure. Lower doses can cause headache, nausea and vomiting. Oral LDsoin mice is 3.7 mg/kg. Amyl nitrite is an effective antidote. 

Caution. The reagents trimethyltriazacyclonane and trifluoromethane sulfonic acid are harmful by inhalation and by contact with skin. Potassium cyanide is highly toxic and produces volatile, poisonous hydrogen cyanide on protonation. All operations must be conducted in a well-ventilated fume hood. Wear appropriate protective clothing, gloves, and eye protection. 

Highly irritating via inhalation. Severe eye irritant.3 Toxic effects similar to those of hydrogen cyanide.1 TLV-STEL-C 0.3 ppm (0.75 mg/m3).4... 

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