WEBVTT - Why is carbon monoxide so poisonous?

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<v Speaker 1>Welcome to Brainstuff from house stuff Works dot com where

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<v Speaker 1>smart happens. Hi, I'm Marshall Brain with today's question, why

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<v Speaker 1>is carbon monoxide so poisonous? Every poison has a particular

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<v Speaker 1>trait that causes it to be poisonous. In the case

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<v Speaker 1>of carbon monoxide, the trait has to do with hemoglobin

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<v Speaker 1>in your blood. Hemoglobin is made up of proteins that

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<v Speaker 1>bind iron atoms. The structure of hemoglobin causes oxygen to

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<v Speaker 1>bind the iron atom very loosely. When blood passes through

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<v Speaker 1>the lungs, the iron atoms and hebi globe pick up

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<v Speaker 1>oxygen atoms. When the blood flows into areas of the

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<v Speaker 1>body that are lacking in oxygen, the iron atoms release

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<v Speaker 1>their oxygen. Carbon monoxide, on the other hand, binds very

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<v Speaker 1>strongly to the iron and hemoglobin. Once carbon monoxide attaches

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<v Speaker 1>it's very difficult to release it. So if you breathe

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<v Speaker 1>in carbon monoxide, it sticks to your hemoglobe and it

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<v Speaker 1>takes up all the oxygen binding sites. Eventually, your blood

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<v Speaker 1>loses all of its ability to transport oxygen and you suffocate.

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<v Speaker 1>Because carbon monoxide binds the hemoglobe and so strongly, you

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<v Speaker 1>can be poisoned by carbon monoxide, even at very low

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<v Speaker 1>concentrations if you're exposed for a long period of time.

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<v Speaker 1>Concentrations as low as twenty to thirty parts per million

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<v Speaker 1>can be harmful if you're exposed for several hours. Exposure

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<v Speaker 1>at two thousand parts per million for one hour will

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<v Speaker 1>cause unconsciousness. Many common devices produce carbon monoxide, including cars,

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<v Speaker 1>gas appliances, woodstoves, and cigarettes. For moralns, and thousands of

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