Hydrogen sulfide nitro azides

The second type of asphyxiants is that which works at the cellular level. Here, they interfere with the mitochondrial cytochrome oxidase s function in the electron transport chain. Because this is the fuel cell for the body, energy production ceases within the cell, with cell death following close behind. The key substance implicated here is cyanide, which is usually found only in a chemical laboratory setting, but can also be a side effect of smoke inhalation. As previously mentioned, hydrogen sulfide and carbon monoxide also have some effect at this site. In addition, azides are cellular asphyxiants. The azides, along with the nitro-ate-ites, are also vasodilators and can cause headaches and hypotension. 

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