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Studies that raised the alarm on C02 levels showed a severe impact on cognitive function at 1,500ppm. Submariners routinely live and work in levels at 5,000ppm.

Studies that raised the alarm on C02 levels showed a severe impact on cognitive function at 1,500ppm. Submariners routinely live and work in levels at 5,000ppm. >baseline level of cognitive performance that's already impacted by chronic exposure to high levels of CO2 If that explanation is true submariners would barley be capable of operating their boats. >Possibly "tolerance" to high levels of CO2, And if that explanation is true new submariners would be barely functional. The most likely explanation is that the study that showed severe impairment at relatively low levels is wrong.

maxbond 6y ago
> Submariners routinely live and work in levels at 5,000ppm. People are telling you that this study may not be reflective of the general population, and you are only demonstrating their point. It seems like you are really invested in a particular outcome for this research. Maybe you should take a step back and try to let go of your biases. Dying on the hill of one particular study is the definition of cherrypicking.
- marchenko 6y ago
  I think the poster has a good point. It's not just the one submariner study he's referencing that's relevant, it's the decades of experience navies of various nations have operating submarine fleets - the armed forces are not shy about collecting physiological data in the service of operational readiness. If the headline article is correct, we should be very concerned that a significant fraction of the world's nuclear weapons are immediately operated by officers experiencing extraordinary CO2 exposure. Every submariner is green at some point (and there are female submariners as well) - how is acclimation handled?
  - maxbond 6y ago
    I agree it's worth investigating. I just found it peculiar how unreceptive they were to the suggestion that the population was unrepresentative, yet how aware they were that the population was, in fact, unrepresentative. The original suggestion, way up thread, was not to overgeneralize studies. This is a huge problem in our society.
    - learc83 6y ago
      I'm not unreceptive . It's entirely possible that fit militarily aged men under a certain height aren't as impacted by high C02 levels. However I find it unlikely that they are completely immune to the effect at a dose 10x higher than what the people in the original Harvard study were exposed to. As to whether long term exposure has a mitigating effect. That's possible, but if the effect is as great as the Harvard study shows, then the navy almost certainly would have noticed the impact on new submariners in the last 80 years. Btw the original Harvard study was mostly college students, so it's hardly representative either. Here's another study that shows no impact on military aged people who aren't submariners https://www.ncbi.nlm.nih.gov/pubmed/31240239 https://www.ncbi.nlm.nih.gov/pubmed/31240239. And here's a study that showed no impact from an introduction of pure C02 (these weren't submariners either) https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?casa_token=MRfFkCB3aywAAAAA%3AuDvTvLLiz_GGRL0sf_pvn_Hq-_l3L6y1T9wsoPEgzkPuS_u1EwSpVVy4lCf7byA-Q-P2PoP89KlOmCNw https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c... And here's another one that shows no cognitive impact at 5,000ppm https://www.sciencedirect.com/science/article/abs/pii/S0360132316300580 https://www.sciencedirect.com/science/article/abs/pii/S03601... All the studies I've seen that do show an impact, aren't using just C02, they are more broadly studying poor ventilation--C02 is just one factor. Every study that isolates C02 level shows nothing. The most likely explanation is that if there is an impact on cognition from poor building ventilation, it's not the C02 doing it. I researched this topic pretty thoroughly a while back. I was worried enough by the hype that I bought a C02 monitor, but after I researched it, I'm not concerned.
      - mleonhard 6y ago
        > Here's another study that shows no impact on military aged people who aren't submariners https://www.ncbi.nlm.nih.gov/pubmed/31240239 https://www.ncbi.nlm.nih.gov/pubmed/31240239 Those are prospective astronauts. I would expect them to be even more tolerant of CO2 and claustrophobia than submariners. > And here's a study that showed no impact from an introduction of pure C02 (these weren't submariners either) https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c.. https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c.... > And here's another one that shows no cognitive impact at 5,000ppm https://www.sciencedirect.com/science/article/abs/pii/S03601.. https://www.sciencedirect.com/science/article/abs/pii/S03601.... These studies back up your claims. Thanks for sharing them. They were both done by the same people. Do you know if anyone else has tried to reproduce their results? I would like to know the specific substances in exhalation that negatively affect humans. CO2 not being one of them would be good news.

maxbond 6y ago

> Submariners routinely live and work in levels at 5,000ppm. People are telling you that this study may not be reflective of the general population, and you are only demonstrating their point. It seems like you are really invested in a particular outcome for this research. Maybe you should take a step back and try to let go of your biases. Dying on the hill of one particular study is the definition of cherrypicking.

marchenko 6y ago
I think the poster has a good point. It's not just the one submariner study he's referencing that's relevant, it's the decades of experience navies of various nations have operating submarine fleets - the armed forces are not shy about collecting physiological data in the service of operational readiness. If the headline article is correct, we should be very concerned that a significant fraction of the world's nuclear weapons are immediately operated by officers experiencing extraordinary CO2 exposure. Every submariner is green at some point (and there are female submariners as well) - how is acclimation handled?
- maxbond 6y ago
  I agree it's worth investigating. I just found it peculiar how unreceptive they were to the suggestion that the population was unrepresentative, yet how aware they were that the population was, in fact, unrepresentative. The original suggestion, way up thread, was not to overgeneralize studies. This is a huge problem in our society.
  - learc83 6y ago
    I'm not unreceptive . It's entirely possible that fit militarily aged men under a certain height aren't as impacted by high C02 levels. However I find it unlikely that they are completely immune to the effect at a dose 10x higher than what the people in the original Harvard study were exposed to. As to whether long term exposure has a mitigating effect. That's possible, but if the effect is as great as the Harvard study shows, then the navy almost certainly would have noticed the impact on new submariners in the last 80 years. Btw the original Harvard study was mostly college students, so it's hardly representative either. Here's another study that shows no impact on military aged people who aren't submariners https://www.ncbi.nlm.nih.gov/pubmed/31240239 https://www.ncbi.nlm.nih.gov/pubmed/31240239. And here's a study that showed no impact from an introduction of pure C02 (these weren't submariners either) https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?casa_token=MRfFkCB3aywAAAAA%3AuDvTvLLiz_GGRL0sf_pvn_Hq-_l3L6y1T9wsoPEgzkPuS_u1EwSpVVy4lCf7byA-Q-P2PoP89KlOmCNw https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c... And here's another one that shows no cognitive impact at 5,000ppm https://www.sciencedirect.com/science/article/abs/pii/S0360132316300580 https://www.sciencedirect.com/science/article/abs/pii/S03601... All the studies I've seen that do show an impact, aren't using just C02, they are more broadly studying poor ventilation--C02 is just one factor. Every study that isolates C02 level shows nothing. The most likely explanation is that if there is an impact on cognition from poor building ventilation, it's not the C02 doing it. I researched this topic pretty thoroughly a while back. I was worried enough by the hype that I bought a C02 monitor, but after I researched it, I'm not concerned.
    - mleonhard 6y ago
      > Here's another study that shows no impact on military aged people who aren't submariners https://www.ncbi.nlm.nih.gov/pubmed/31240239 https://www.ncbi.nlm.nih.gov/pubmed/31240239 Those are prospective astronauts. I would expect them to be even more tolerant of CO2 and claustrophobia than submariners. > And here's a study that showed no impact from an introduction of pure C02 (these weren't submariners either) https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c.. https://onlinelibrary.wiley.com/doi/full/10.1111/ina.12284?c.... > And here's another one that shows no cognitive impact at 5,000ppm https://www.sciencedirect.com/science/article/abs/pii/S03601.. https://www.sciencedirect.com/science/article/abs/pii/S03601.... These studies back up your claims. Thanks for sharing them. They were both done by the same people. Do you know if anyone else has tried to reproduce their results? I would like to know the specific substances in exhalation that negatively affect humans. CO2 not being one of them would be good news.