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Carbon Monoxide


This page is still in preparation. It will give a brief account of the sources and very harmfull and often fatal consequences which may arise from exposure to this highly toxic gas. 


Carbon monoxide arises from the incomplete combustion of carbon, and usually people poisoned by it have been exposed in confined spaces or with poor ventilation. Examples include faulty gas burning appliances or irresponsible behaviour such as barbecues indoors. Some other sources may also generate CO eg from the endogenous metabolism of dichloromethane (used as a paint stripper). 

Carbon monoxide has approximately the same density as air, being very marginally lighter (CO=14, air=14.4). One should assume that it mixes freely with ambient air.

Carbon monoxide is completely odourless. Therefore smell cannot be relied upon to provide warnings of this treacherous gas. Open solid fires should be assumed to be constantly generating this gas. Gas fires should be assumed to be generating carbon monoxide if the flame is yellowish. 

It is wise to use carbon monoxide detectors where there are potential sources of this lethal gas. In the UK, stringent legally binding measures governing the installation and maintenance of appliances which could gnerate carbon monoxide have made poisoning by this gas much less common than it used to be.


Health Effects:

Carbon monoxide (CO) is a highly toxic gas which interferes with cellular respiration just like  hydrogen cyanide and hydrogen sulphide. It acts as a potent chemical asphyxiant, combining with haemoglobin in red blood cells and with intracellular cytochromes and thus rapidly stopping oxygen from access to cellular metabolism (just like gases such as carbon monoxide and hydrogen cyanide).

Unfortunately the symptoms of poisoning by this insidious gas can be readlily and mistakenly attributed to other things or simply ignored until it is too late. The commonest is headache, but other common ones include being tired, feeling sick and confused. Symptoms may vary depending upon the concentration, duration and pattern of exposure. Ultimately unless the victim is removed from the source and treated as necessary the outcome can be fatal.

Read more about the symptoms of poisoning by this gas.

Sadly some people still do ignorant and stupid things resulting in incomplete combustion in confined spaces with fatal or very serious consequences.