Carbon monoxide (CO) is a tasteless, nonirritating, odorless, and colorless gaseous substance. The main source of CO production is the combustion of fuels. Exposure at the workplace occurs in blast-furnace operations in the steel industry and when gasoline- or propane-powered forklifts, chain-saws, or other machines are used in confined spaces, such as companies, tunnels and mines. Environmental exposure to CO can occur while traveling in motor vehicles; visiting urban locations with heavily traveled roads; or cooking and heating with domestic gas, kerosene, coal, or wood; as well as in fires and by environmental tobacco smoke.

Furthermore, Carbone monoxide has 200 times more affinity for haemoglobin than oxygen. Then, Carbone monoxide when inhaled combines with haemoglobin to form carboxyhaemoglobin.

                       Hb + CO → COHb

As result, oxygen-carrying capacity of haemoglobin decreases and the blood becomes oxygen-deficient. This leads to suffocation and even death depending upon the concentration of CO in the blood.

References:

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