Date: Around 1999
how does exposure to cyanide cause death immediately.
Cyanide binds to hemoglobin, the blood's oxygen-carrying protein, better
than oxygen does. When cyanide is bound to the hemoglobin, the blood can't
pick up oxygen in the lungs and carry it to the body's tissues, and the
body's cells die from lack of oxygen.
You know that inhalation of hydrogen cyanide, or ingestion
of cyanides causes death. HCN, hydrogen cyanide is a
highly volatile liquid and that hasten its lethal effect.
The reason of this is the inhibition of the oxidative
processes of the cells. Rapid death may be caused
by swallowing as little as 300 milligrams of the cyanides
or inhaling 100 milligrams of HCN.
The poisoning results from the following: the cyanide
ion [ (CN) minus} is quite small and quickly makes its
way into the body cells, where it binds to the iron in
the heme of one of the cytochromes. As an immediate
result the respiratory chain shuts down by inhibiting
electron transfer. Cell respiratory process then ceases
and the period from ingestion to death is only a few
Because the poison acts so fast, recovery from
sublethal doses will depend from the promptness
of antidotes administration.
Since cyanides are used in many industrial process
always there are possibilities of fatalities from
occupational poisoning. An emergency treatment
includes amyl nitrite, sodium nitrite or a 25%
solution of sodium thiosulfate.
One must be very careful then!
Thanks for asking NEWTON!
(Dr. Mabel Rodrigues)
Cyanide is competes with oxygen as the final electron acceptor in the
electron transport chain. Without oxygen the body cannot complete cellular
respiration which makes energy available to the body.
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Update: June 2012