Carbon monoxide asphyxiation

Asphyxiant Simple asphyxiants are inert gases which deplete the oxygen supply in the breathing air to below the critical value of J8% by volume, such as gaseous fuels or nitrogen. Chemical asphyxiants, such as carbon monoxide and hydrogen cyanide, have a direct biological effect. 

Chemical asphyxiant A substance that interferes with the absorption or utilization of oxygen in the body, e.g., carbon monoxide. 

The fact that the main direct cause of death in fires has always been the toxicity of combustion products was already discussed in the National Fire Protection Association (NFPA) Quarterly in 1933 [34]. Smoke contains mainly two types of toxic gases asphyxiants and irritants, but the individual toxic gas associated with the largest fire hazard is carbon monoxide (CO). 

Asphyxiant A gas or vapor which, when inhaled, may lead to asphyxia. Examples of asphyxiating materials are carbon dioxide and carbon monoxide. 

NOXIOUS CAS. Any natural or by-product gas or vapor that has specific toxic effects on humans or animals (military poison gases are not included in this group). Examples of noxious gases are ammonia, carbon monoxide, nitrogen oxides, hydrogen sulfide, sulfur dioxide, ozone, fluorine, and vapors evolved by benzene, carbon tetrachloride, and a number of chlorinated hydrocarbons. Oases that act as simple asphyxiants are not classified as noxious. See also Pollution (Air). 

Narcotic gases or asphyxiants cause a decrease in oxygen supplied to body tissue, resulting in central nervous system depression, with loss of consciousness and ultimately death. The severity of the effects increases with increasing dose.2 The main asphyxiants, carbon monoxide and hydrogen cyanide, have been widely studied and are the best understood.5... 

If the corpses had indeed appeared blue, death certainly would not have been due to carbon monoxide poisoning. A bluish appearance could, however, have been an indication of death from asphyxiation, /. e., from lack of oxygen.. 

Asphyxiates paralyze the respiratory center and weaken the body. They disturb the maintenance of an adequate oxygen supply to different systems in the body. The most common asphyxiates are carbon dioxide, carbon monoxide, cyanides, helium, nitrogen, and nitrous oxide. 

Designated work areas should be established for handling materials with a high degree of acute toxicity (such as chemicals with corrosive effects, e.g., nitric, sulfuric, and hydrochloric acids hydrofluoric acid sodium hydroxide or chemical asphyxiants such as carbon monoxide and hydrogen sulfide). 

Henderson, M., Haggard, H.W. (1921). The elimination of carbon monoxide from the blood after a dangerous degree of asphyxiation, and therapy for accelerating elimination. J. Pharmacol. Exp. Ther. 16 11-20. 

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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