Is the Use of Cyanogen Bromide Forbidden in Hospitals

Nomen est omen, this triatomic molecule (Fig. 4.2) seems destined to induce fears because of the word cyan in its name. It is or was also mentioned under names such as bromine cyanide, bromocyan, bromocyanide, bromocyanogen, cya-nobromane, and cyanobromide, none of which soimd less ominous than cyanogen bromide. 

Cyanogen bromide is a volatile solid, which dissolves readily in water, diethyl ether, and alcohol. It is a highly toxic substance through inhalation, ingestion and skin contact. It is usitally considered about 2-3 times less toxic than hydrogen cyanide, but the exact lethal dose is imknown. In the developed coirrttries, the permissible workplace exposure limits in the air are 5 mg/m (as cyanide, time-averaged concentration in an 8-h shift), and 20 mg/m (as cyanide, peak concentration). 

Cyanogen bromide is prepared by reacting metal cyanides with bromine in water or carbon tetrachloride. The properties of cyanogen bromide resemble those of interhalogens (a compoimd formed by several halogens). When it reacts with 

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