# Stale air / high CO2 may decrease your cognitive function

If you're in a closed space, you may want to open a window.

before the industrial revolution, the atmosphere had 300 parts-per-million (PPM) of CO2. today, this number is already above 400 on average, and 500 in urban areas.

but CO2 doesn't just effect the environment, high enough levels of it also effect [our bodies](https://en.wikipedia.org/wiki/Hypercapnia), and our minds.

so let's leave the atmosphere for a bit, and go inside. [one study](https://ehp.niehs.nih.gov/doi/pdf/10.1289/ehp.1510037) checked office employee's decision making skills at various CO2 levels, here some of the results:

**1000ppm**

this level is common at poorly ventilated spaces like a workrooms/offices. and one [study on schools](https://www.gwern.net/docs/co2/2015-stafford.pdf) in several US districts found 50% of classrooms to have this level.

at this CO2 level the cognitive function in the office experiment _decreased by 15%_.

  

**1400ppm**

this level can also be reached at the places described above.

here cognitive function **decreased by 50%!**

  

**2000ppm**

from this level onward some people described other side effects such as: slight nausea, loss of attention and poor concentration, sleepiness, headaches, and increased hearth rates.

and still, these levels aren't uncommon -

  

**4000ppm**

this is common in cars and bedrooms (closed spaces which are either small, you spend a long time in, or both. and the side effects increase.

  

**8000-10,000ppm**

motorcycle helmets can reach these levels. Being in such an environment for long times can harm your long-term health.

* * *

**So what can you do?**

1\. simply open a window! (at least in this part of the century)

  

2\. you can get some plants for your room or office -

The [NASA Clean Air Study](https://en.wikipedia.org/wiki/NASA_Clean_Air_Study) looked at about two and half dozen plants, and [recommends](https://www.ted.com/talks/kamal_meattle_on_how_to_grow_your_own_fresh_air#t-227887) these tree plants: [Areca Palm](https://en.wikipedia.org/wiki/Dypsis_lutescens), [Snake Plant](https://en.wikipedia.org/wiki/Sansevieria_trifasciata),  and [Money Plant](https://en.wikipedia.org/wiki/Epipremnum_aureum).

[This lung institute guide](https://lunginstitute.com/blog/top-5-plants-for-increasing-oxygen/) seems to be based on this study, so i suggest reading it.

  

3\. buy a CO2 monitor if you want to always know in what environment you're in. though, these seem cost quite a bit (for a reason unclear to me). so i don't know if it will really benefit you. i know i won't bother.

* * *

The IPPC reported that CO2 levels will be, by the end of the century, between [541 and 970ppm](https://en.wikipedia.org/wiki/Global_warming#cite_ref-101). if we extrapolate from the previous study, this may mean a 10-15% decrease in the cognitive function of humanity as a species (and even more than the previous results in closed spaces).

some studies found evidence that [air pollution can harm the brain itself](https://www.sciencemag.org/news/2017/01/brain-pollution-evidence-builds-dirty-air-causes-alzheimer-s-dementia).

Should this change our attitude towards climate change as a catastrophic risk?

* * *

This has been brought to my attention by [this video series](https://www.youtube.com/playlist?list=PL1iviMOHUg8756PdpBqr9JDUt2eiGX_xb) and [this video](https://www.youtube.com/watch?v=1Nh_vxpycEA&t=0s). give it a look if you want to see for yourself how high CO2 levels affect a person