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Any contraindications of inhaling pure O2?

  1. Oct 9, 2012 #1
    As cited in any biology book, humans require oxygen for functioning properly. Using non-experimental-based results, and plain logic, an air with higher concentration of O2 gives any human a better performance. When mountain climbers climb mountains, they slowly require more oxygen. If they don't get it, their capabilities go down. If any person living in a high city goes to the sea, he/she could run faster, higher or anything similar because a slight rise of the quantity of oxygen. This only tells me that pure oxygen could have a 'boost' on animals, incluiding humans.
    But this link here jumps objecting.
    So I wanted to ask a scientific community about it. Whaddya think, or know?
    And yes, I'm aware that, in a scenario that there is not a single problem, I'd have a hard time getting back into an average 21% ox'd air.
  2. jcsd
  3. Oct 9, 2012 #2


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    Staff: Mentor

    This doesn't address the study you found and the mechanism that they are studying, but COPD is sometimes considered a contraindication for 100% O2 delivery:


    However, as that article points out, often our field EMS protocols still call out 100% O2 for COPD patients in respiratory distress -- the benefits of the O2 can outweigh the worries about the hypoxic drive, at least in the temporary pre-hospital EMS transport context.
  4. Oct 10, 2012 #3

    Andy Resnick

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    I've wondered about this as well- it's possible to become disoriented when breathing pure O2 for an extended time (a few minutes or so). The best answer I've heard is that the O2 will over time displace CO2, which leads to a pH imbalance.
  5. Oct 10, 2012 #4


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    Gold Member

    Oxygen toxicity has been known for a 100 years or so.

    and from

    Oxygen toxicity occurs when oxygen in the body exceeds a safe partial pressure (PPO2).[2] In extreme cases it affects the central nervous system and causes a seizure, which can result in the diver spitting out his regulator and drowning. While the exact limit is idiomatic, it is generally recognized that Oxygen toxicity is preventable if one never exceeds an oxygen partial pressure of 1.4 bar.[21] For deep dives—generally past 180 feet (55 m), divers use "hypoxic blends" containing a lower percentage of oxygen than atmospheric air. For more information, see oxygen toxicity.

  6. Oct 15, 2012 #5
    In welding school they taught us that sniffing the pure oxygen from the welding oxygen bottle will send you dizzy. However, they also cautioned that it can kill, by suppressing breathing. The reason is that breathing is a response to CO2 concentration. So medical oxygen has a small amount of CO2 in it to stimulate breathing.
  7. Oct 17, 2012 #6
    Remember that NASA had plans for the lunar astronauts to breath pure oxygen in the Apollo spacecraft on the way to the Moon, a week long (or more) time period. Of course, that didn't work out so well since Apollo 1 burned up during a test, killing three astronauts.
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