When heated to >3000C the salt breaks down explosively into sodium and nitrogen. This property led to its use in car collision air bags. If placed in contact with metals, the salt (or solutions of the salt) can form unstable/ explosive azides. Acidification of a solution, or the addition of acid to the salt itself, can also result in the production of highly-toxic hydrazoic acid (HN3) which is a volatile, shock-sensitive explosive gas. Despite this explosive property, a solution of the salt in water is an effective end of life drink. Quantities as little as 2gm will reliably end life. Let us explain.
Toxic Characteristics
The exact mechanism of toxicity of sodium azide is not fully understood. Two mechanisms of operation are suggested.
The dissolved salt is relatively tasteless and is rapidly hydrolysed on contact with mucosa to hydrazoic acid. This has some irritant effect in the throat and, at higher concentrations, the direct effect of azide on cytochrome oxidase can cause cellular asphyxia and death in those organs with the highest need for oxygen (eg. the brain and heart). This is known as histotoxic hypoxia.
The production of nitric oxide with its effect on the central nervous system, carotid baroreceptors and potent vasodilation with associated blood pressure drop can explain the reported
