Carbon monoxide poisoning
The science behind it
Carbon monoxide poisoning causes a range of symptoms while in the body and blood
stream. It can damage cells resulting in short term symptoms and effects and long term symptoms and effects.
Carbon monoxide gas is odorless, colorless, tasteless, non-irritating, and toxic to humans and animals. It can
cause serious damage while it is being breathed and also in the days and weeks after being breathed.
Carbon monoxide displaces oxygen in the blood and starves cells of oxygen. It also disrupts other processes in
the body which can further damage, destroy, and/or impact cellular functioning.
The amount of oxygen in blood is referred to as oxygen saturation. It is a measurement of the percentage of the
total number of oxygen carrying "locations" in the blood that are actually carrying oxygen.
Arteries, which carry blood to cells, are usually 95%+ saturated with oxygen. When oxygen saturation falls below
80%, cells do not receive enough oxygen to continue to function normally. At 30% oxygen saturation, cells are
Normally, oxygen binds with the hemoglobin (Hb) in red blood cells to form oxyhemoglobin (O2Hb). It also dissolves in small amounts in the liquid component of blood (plasma).
Carbon monoxide is particularly dangerous because the attraction (bond) between carbon monoxide and hemoglobin
is 240 times stronger than the attraction (bond) between oxygen and hemoglobin.
When breathed, carbon monoxide reacts with hemoglobin (Hb) in red blood cells and forms carboxyhemoglobin (COHb).
Carbon monoxide molecules are easily able to displace oxygen in the blood causing oxygen saturation levels to
drop fast. This means that even a small amount of inhaled carbon monoxide is dangerous and can be fatal.
Lack of oxygen can quickly result in damage affecting the brain, nervous system, heart, endocrine (regulatory) system, organ functioning, and can
cause other damage.
Even if normal oxygen (and saturation) is restored, damaged cells will continue to die over the next few
minutes, hours, days and weeks.
The brain does not regulate breathing based on the amount of oxygen in the blood. It regulates breathing based
on levels of carbon dioxide (CO2) in the blood.
A carbon monoxide poisoning victim can easily lose consciousness without realizing that anything is wrong
because the brain is unable to recognize that oxygen levels are falling dangerously low.
Carbon monoxide poisoning has biochemical effects that are more complex and serious than just oxygen deprivation
alone. It also interferes with cellular functioning by attaching itself to myoglobin and cytochrome enzymes.
Other areas of functioning are impacted and cause carbon monoxide poisoning:
- Disruption of a normal fixed ratio between oxygen, carbon monoxide and nitric oxide in the body
- Damage to blood vessels
- Damage to the nervous system
- Immune system responses during recovery
In the weeks following exposure, damage to blood vessels and these other areas of functioning can then cause
damage to myelin, an important protein that coats neurons. Myelin helps transmit signals more quickly within the nervous system and brain. The
damage to brain cells triggers the immune system, which then responds by causing brain inflammation, which in
turn causes [more] brain damage.
This "biochemical domino effect" is what causes delayed symptoms and many of the long term symptoms and effects suffered by victims of carbon
The amount of damage caused by carbon monoxide poisoning depends on many factors including the levels of carbon monoxide in the air, the length of time it is
breathed, the level of physical activity while exposed, age, pre-existing health conditions, and overall health.
There are other risk factors that
increase the possibility of damage.
If exposed to elevated levels of carbon monoxide, any person or animal will develop symptoms as long as unsafe levels remain in the body/blood stream; however, people
respond differently to the same level of exposure.
The biochemical effects of carbon monoxide poisoning while in the body range from mild to severe in
people with the same level of exposure. The ongoing symptoms and after effects can range from nothing to
severe in people with the same level of exposure.
Medical professionals can learn more about carbon monoxide treatment here.
Also see carbon monoxide poisoning and
multi sensory sensitivity.
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