CHEMISTRY OF CARBON MONOXIDE POISONING
By Kuljeet Singh
Carbon monoxide is a colorless , odorless ,tasteless flamable gas which is made up of carbon and oxygen atom. Its chemical formulae isCO, molar mass 28.010g/mole , density 789 kg/m3 , melting point – 205.02 c ,boiling point -191.2 c and highly soluble in water .carbon monoxide is mostly produced by incomplete burning of fossil fuel containing mostly carbon . About 0.001% carbon monoxide is present in our atmosphere and less than 0.1% can be lethal which cause death. At present CO is one of the dangerous poison in our environment . CO poisoning can be acute sub acute and chronic.
Human are the main source for the production of carbon monoxide by burning of charcoal , wood ,kerosene oil and natural gas .Heating and cooking also produces carbon monoxide . Human body also directly produces CO as a byproduct of haemoglobin degradation resulting in baseline carboxyhaemoglobin which have saturation of 1-3% in non smokers and 10 – 15% in havey smokers . A heavy smoker produces 400 to 500ppm of carbon monoxide while actively smoking. Majority of the death each year are caused by inhalation of tobacoo smoke .
According to a report of WHO more than half of the death each year are caused by motor vehicle exhaust . stripper can also poisoned by carbon monoxide , because the fume arereadily absorbed and converted to CO in the liver .
The amount of CO absorbed depends upon the concentration in the environment . CO is highly unstable gas which have the capacity to bind with our blood haemoglobin faster than the oxygen to form poisonous chemical carboxyhaemoglobin COHb which is stable .
CO + Hb COHb
Carboxyhaemoglobin [COHb] is responsible for decreasing oxygen concentration in our body . Many of study shown that the excessive uptake of CO will cause neurologic damage.
When CO bind with cytochrom oxidase it will cause mitochondrial dysfunction which result into oxidative stress .Carbon monoxide also cause serious ill effect in pregnant womens ,because it will directly effect foetus which is initially grown in mother womb. Firstly it increases the level of CO in foetus and convert CO into COHb , when the concentration of COHb is increases in foetus it will directly shift to mother .
SYMPTOMS OF CO POISONING
The person have initial stage CO poisoning symptom include flu but without rise in body temperature. If this happen all cooking and heating appliances must be switched off ,all windows opened. The individual is exposed to 9-12 hour CO poisoning the symptoms may experience loss of balance ,vision problem , memory problem ,eventual loss of consciousness . if these symptom are observed there is full chance of recovery . But when the person have indulges in CO poisoning more than 2 months symptoms include Headache , nausea , dizziness , bizerre behavioural , abnormalities decline intellect , memorial distrubance , chronic cough etc. in this condition there is less chance of recovery .
The initial treatment of CO poisoning is to wear non-re-breather mask which supplies 100% oxygen to remove COHb from blood . Other method are HYPERBARIC OXYGEN TREAPHY .During this method the patient is placed in a pressure chamber and giving 100% oxygen at a pressure greater then 1atm. HBO at a 2.5 atm reduces the half life of COHb within 20 minute . It also increases the accelerated rate of CO eliminate from blood .
8Do not oven for heating .
8Make sure that all rooms are well ventilated and vents are not blocked.
8Wear mask while using product that contain methyl chloride [CH3CL ]
8Do not leave any vehicle in starting mood [motor bike , car etc]
8Do not use charcoal on an indoor barbecue
8To prevent leakage of CO gas by keep appliances in proper working order and use them safely
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2. Robkin MA. Carbon monoxide and the embryo. Int J Dev Biol 1997; 11:283-9.
3. Tomaszewski C. Carbon monoxide poisoning: Early awareness and intervention can save lives. Postgraduate Medicine 1999; 105: 345-54
4 MJAFI 2007; 63 : 362-365 Carbon monoxide poisoning
Kuljeet Singh is an MSc 3rd Sem student of Himavati Nandan
Bahuguna Garwal central University e-mail email@example.com