Toxicity of hydrogen cyanide

Smith, L.L., S.J. Broderius, D.M. Oseid, G.L. Kimball, and W.M. Koenst. 1978. Acute toxicity of hydrogen cyanide to freshwater fishes. Arch. Environ. Contam. Toxicol. 7 325-337. 

When comparing the available acute lethal toxicity information for cyanide compounds, it was concluded that, for oral exposure, the molar lethal toxicities of hydrogen cyanide, sodium cyanide, and potassium cyanide are similar. Rabbits appeared to be more susceptible to the lethal toxicity of these three compounds than rats (Ballantyne 1988). 

Caution Because of the toxicity of hydrogen cyanide, this procedure should be conducted in a well-ventilated hood and rubber gloves should be worn. (See also Note 3.)... 

Ballantyne, B. (1984). Comparative acute toxicity of hydrogen cyanide and its salts. In Proceedings of the Fourth Annual Chemical Defense Bioscience Review (R.E. Lindstrom, ed.), US Army Medical Research Institute of Chemical Defense, Maryland. 

Ballantyne, B., Acute inhalation toxicity of hydrogen cyanide vapor to the rat and rabbit. Toxic Sub. J., 13, 249-282, 1994b. 

Matijak-Schaper, M. and Alarie, Y., Toxicity of hydrogen cyanide and low oxygen, J. Combust. Toxicol., 9, 21-61, 1982. 

Some compounds can pose either a reactive or a toxic hazard, depending on the conditions. Thus, hydrocyanic acid (HCN), when used as a pure liquid/ gas in industrial applications, is incompatible with bases because it is stabilized against (violent) polymerization by the addition of acid inhibitor. HCN can also be formed when cyanide salt is mixed with an acid. In this case, the toxicity of hydrogen cyanide gas, rather than the instability of the liquid, is the characteristic of concern. 

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