Rising carbon dioxide levels now detected in human blood

https://phys.org/news/2026-02-carbon-dioxide-human-blood.html

by wkrsz • 5 months ago

126 132 5 months ago

This actually has me just as concerned as rising temperatures. And its a pretty hard thing to argue against, no matter your politics. Elon even brought it up when he did that interview with Trump in late 2024 to convince him that we should still care about CO2 levels in the atmosphere, even if you think the threat of a changing climate is overblown. Trump really had no response.

Tade0• 5 months ago

USA (along with the rest of the western world) is a huge cumulative emitter:

https://ourworldindata.org/contributed-most-global-co2

But a distant second in per year emissions:

https://www.worldometers.info/co2-emissions/co2-emissions-by...

The EU, not listed here, sits between the US and India at about 3.05 billion tonnes.

It's all up to China, which took over a huge chunk of the world's manufacturing. And all up to us, buying Chinese products.

bspinner• 5 months ago

The EU isn't listed, because the EU is not a country.

Sorting the table by "per capita" is much more interesting IMHO.

triceratops3• 5 months ago

The cumulative emissions represent the PPM increase today. So that's a very relevant statistic. I don't know why you're ignoring it.

China also reduced their emissions last year while the US increased them. https://news.ycombinator.com/item?id=45108292

Stop pointing fingers. Start working.

piloto_ciego4• 5 months ago

figuring out who to blame is not the problem here, we need to figure out how to fix it.

ThomW• 5 months ago

"Yes, the planet got destroyed. But for a beautiful moment in time we created a lot of value for shareholders.“

toomuchtodo7• 5 months ago

Clean tech will save the day (low carbon generation, batteries, electrification trajectories and rate of change, broadly speaking), but the global fossil industry will need to be dismantled faster than some will like. It is a matter of survival, not politics or economics. My hunch is there are not many globally who want to suffocate while trying to exist for shareholder value.

lapcat13• 5 months ago

My hunch is there are not many who want to suffocate while trying to exist for shareholder value.

Have you... read the news lately? You say it's not a matter of politics, but the politicians are absolutely trying to roll back the clock, push dirty tech, eliminate all environmental protections and regulations.

obsidianbases1• 5 months ago

Where can I find some of that optimism in 2026?

throawayonthe2• 5 months ago

that very much is a matter of politics, people should stop being afraid to acknowledge it

real politics are often concerned with survival

tw043• 5 months ago

I think you’re grossly underestimating how much the average American can deny with the assistance of social media.

The number of people I personally know who thought the country was going to end on J6 who now call the entire thing a “political hoax” breaks my brain.

Not to mention the endless posts about “where are all the people claiming COVID was so deadly now?” Who literally completely ignore the MILLIONS of deaths caused by COVID…

Until these people have their own son or daughter killed by X - they’ll happily claim it’s not actually a problem. Or find something completely unrelated to blame instead if it doesn’t align with their Twitter feed.

lenerdenator3• 5 months ago

I'd be willing to bet they go the Spaceballs route and make cans of oxygen a must-have item before they cut the emissions.

boringg6• 5 months ago

Nuclear will save the day in combination with clean tech.

Clean tech on its own is too slowly to be meaningfully impactful by the time we need it.

pocksuppet2• 5 months ago

But everyone wants everyone else to suffocate while delivering shareholder value for themselves. Classic Prisoner's Dilemma.

AlexandrB• 5 months ago

My hunch is there are not many globally who want to suffocate while trying to exist for shareholder value.

I hate this kind of hyperbole because it obscures the real dangers. No one is going to suffocate any time soon. Atmospheric CO2 is around 450ppm. The CO2 in a meeting room of a typical office can easily reach 1500ppm or more[1]. Is everyone in meeting rooms "suffocating"?

[1] https://www.popsci.com/conference-carbon-dioxide-tired-offic...

goodpoint• 5 months ago

I think you are being downvoted because people only skim "Clean tech will save the day" without reading the whole text.

qingcharles2• 5 months ago

I thought the current policy was "Drill, baby, drill!"?

davidw3• 5 months ago

And parking is abundant!

amelius2• 5 months ago

If you have the money for it.

https://easypark.rs/news/cheapest-countries-to-park-in/

wise_young_man• 5 months ago

And in many places makes more than minimum wage.

throw0101a2• 5 months ago

A few years old now, but still worth checking out:

* https://en.wikipedia.org/wiki/The_High_Cost_of_Free_Parking

throw0101a2• 5 months ago

For those unaware, this is the dialogue/caption in Tom Toro's 2012 New Yorker cartoon:

* https://www.newyorker.com/cartoon/a16995

* https://tomtoro.com/cartoons/

* https://condenaststore.com/featured/the-planet-got-destroyed...

highview• 5 months ago

It's like the ending for the Dinosaur TV series.

gcanyon2• 5 months ago

Higher carbon dioxide makes us dumber: https://pmc.ncbi.nlm.nih.gov/articles/PMC7229519/

I wonder how long before in-home CO2 extraction becomes a thing.

amelius2• 5 months ago

We'll have AGI not because the AI becomes smarter but because humans become stupider.

rozap• 5 months ago

And the AI build out will release more co2, making the crossover point even closer.

This is actually really funny to think about.

kibitzor• 5 months ago

CO2 increase of 400ppm decreases cognitive function by >20% [1]

I frequently send this medium article [1] to friends + family for a basic dive into how CO2 affects our thinking and abilities at various levels in common areas.

The article cites a study [2] which graphs cognitive score for different activities at different CO2 concentrations. Each activity's cognitive score is worse at higher CO2 concentrations, EXCEPT "focused activity" or "Information search" (up to some point)

[1, note it is from 2016] https://medium.com/@joeljean/im-living-in-a-carbon-bubble-li... [2]https://pubmed.ncbi.nlm.nih.gov/26502459/

boringg6• 5 months ago

That article really needs a pre-and post fixing his house.

I find it hard to believe that stat you provide -- seems like a bit of a shiny lure without much merit.

Maybe if CO2 PPM wasn't so high I could make sense of it.

eitau_1• 5 months ago

I've started questioning this premise given that concentration of CO2 in the lungs (while resting) never falls below 10000ppm (I'm possibly underestimating this number).

Though I'm not excluding the possibility that indoor CO2 concentration strongly correlates with cognitive underperformance, which may be caused by other compounds emitted by human body.

HoldOnAMinute3• 5 months ago

It will be mandated by the state of California for new homes and office buildings.

RobGR• 5 months ago

I've thought about making a C02 scrubber for indoor use. The simplest way, using commercial lime, would mean replenishing a consumable to keep it going. The C02 scrubbers that acquarium owners use also don't seem to be able to be regenerated.

I think it would be interesting to see what effect, if any, an indoor C02 level of near 0 would have on humans and mammals. Because your blood has to stay in a narrow PH range, and C02 is part of maintaining that, I wouldn't presume it would be good.

I think a small desktop C02 scrubber might have a market in the same demographic that pays for air ionizers, de-ionizers, HEPA filters and incense burners.

Karawebnetwork• 5 months ago

The high school my friend's kids attend installed CO2 sensors during the pandemic as an indirect way to measure airflow.

It turned out the building had been sealed extremely tightly to keep out the winter cold and because it is old, it does not have a proper HVAC system.

They discovered that CO2 levels stayed around 1200 ppm throughout the entire winter, sometimes even higher. This had likely been the case for decades.

It is a school in a small, low‑income town. I cannot help wondering how many kids were labeled as underperforming when they were actually struggling with the effects of chronically elevated CO2 levels.

fullstop• 5 months ago

I went to a Catholic school and had to attend services. I thought that I was just bored, but I'm pretty sure that my yawning had more to do with elevated CO2 levels.

api• 5 months ago

This is honestly much, much scarier than climate change. We can adapt to a changing climate but not if we're losing IQ and focus.

WorldMaker5• 5 months ago

I have friends that fell down air monitoring rabbit holes in the situation of the early 2020s and one of the things they have remained obsessed about is home CO2 levels and have active monitoring equipment and "pager alerts" and other things setup.

Home carbon capture is sort of a thing already: buy more houseplants, keep them alive and healthy.

Though the most common home interventions for now are still "open a window" and/or "run a fan to circulate the air better". I suppose it's neat that we can home automate that, if you are willing to invest in that.

squeegmeister• 5 months ago

House plants make too minor a difference to be worthwhile.

Opening windows is better but if you want a more energy efficient solution you should invest in a HRV/ERV

gcanyon2• 5 months ago

I can't find it now, but I saw a video where a guy was trying to offset just the CO2 he produced himself with plants.

   1. He gave up on "plants" because they were nowhere close to offsetting him.
   2. Switching to algae, he used a 55 gallon drum of it because the numbers said that would work. He gave up when the CO2 level reached something like 2000 ppm
   3. He ended up with something like 3 drums, as well as special mixers to make sure the algae got access to as much CO2 as possible, and he had lights focused on the algae drums to make them as efficient as possible, and he still ended up barely keeping the CO2 at the "dangerous but not completely toxic" level, and it wasn't stable either.

Plants are a terrible way to try to manage CO2.

stuaxo• 5 months ago

Plants grow faster (but not better) with more Co2 I wonder if this could be related to global obesity ?

tonyedgecombe2• 5 months ago

If we were only eating plants then there would be no obesity crisis.

zdragnar4• 5 months ago

You'd be amazed at what you can do to yourself with enough fried potatoes and refined sugar.

zdragnar4• 5 months ago

There's an oversimplified assumption here that the plants will be less nutritious, and so people will eat more calories to make up for the deficit.

I suspect the presence of protein, fats and sugars influence the hormone production regulating appetite far more than these changes account for. I would expect the same health issues to be affecting other animal species in just as drastic a measure as humans if it were true, and also that global obesity happened at a more uniform pace rather than coinciding with the introduction of modern western eating habits and lifestyles.

hxorr2• 5 months ago

It's not just an assumption, there is research that shows this.

For example: https://www.scientificamerican.com/article/as-co2-levels-ris...

More specifically, yes, protein content decreases with rising CO2 levels. Maybe not enough to cause obesity on its own, but enough to be a compounding factor. Especially when your staple is, say, rice -- which is what the paper linked above looks at.

beejiu• 5 months ago

There is actually a hypothesis around this, but I don't think it's really been investigated: https://www.nature.com/articles/nutd20122

ArnoVW• 5 months ago

That would work if obesity levels increased equally across the globe. But even if obesity does increase globally, there are very wide disparities. Contrary to popular belief, there US is not the world.

zug_zug• 5 months ago

Humans evolved in an atmosphere containing roughly 280–300 ppm of CO₂. The average annual increase over the past decade has been about 2.6 ppm per year, with 2024 recording a 3.5 ppm rise.

So currently we're at 428 with 3.5 increase per year, yeah, that's scary if it doesn't slow down soon. Makes you wonder about what indirect health side-effects that could have on us.

lenerdenator3• 5 months ago

I'm not a doctor, but I reckon it'd be same as any other case of carbon dioxide poisoning.

apopapo• 5 months ago

It makes us dumber and dumber.

pocksuppet2• 5 months ago

Chronic exposure to CO2 levels above normal but below acute toxicity makes us dumber and more irritable.

Xiol• 5 months ago

Good job we can outsource all our thinking to an agent, now.

piloto_ciego4• 5 months ago

I literally said this down below and got down voted. This has been my theory for a few years now. It's not the only thing, but the flynn effect has certainly reversed.

chneu2• 5 months ago

When the wildfires during COVID hit some folks did some work to figure out how much of a cognitive effect wildfire smoke has on the brain. Its pretty staggering.

https://pmc.ncbi.nlm.nih.gov/articles/PMC9196888/

Essentially, this affects every person and animal on the planet.

piloto_ciego4• 5 months ago

Literally said this down below and got downvoted... but it's a big deal and nobody is talking about it really - indoor levels are much higher.

thesz• 5 months ago

Exercise rises CO2 levels in blood and there are specific exercises to increase CO2 tolerance. Also, extra ventilation during very long exercises (hours) lowers CO2 blood level.

As the recovery from aerobic and resistance exercises also increase ventilation, I think we should just train a little more.

jmclnx• 5 months ago

Related but flagged link:

https://news.ycombinator.com/item?id=47202183

throawayonthe2• 5 months ago

i wonder how much specifically indoor co2 levels and levels in dense/industrial affect it

also is it accurate to say that the blood co2 level is mostly a snapshot of the moment blood is drawn? or is it affected by longterm environment

hxorr2• 5 months ago

This is compounded by modern lifestyle factors such as staying indoors more, keeping the windows closed to help the aircon/heating be more efficient, etc.

I think a lot of people would be surprised at the CO2 level in different indoor environments they spend time in each day.

NoSalt• 5 months ago

I recently purchased a small CO₂ detector off Amazon for the house and work. So far, so good ... hovering around 450ppm.

bob1029• 5 months ago

The human body has a fairly elegant regulation mechanism for handling variance in things like CO2:

https://en.wikipedia.org/wiki/Bohr_effect

I think regular exercise can help to offset some of the effects of rising CO2 levels. Clearly not an end game solution but it's something to consider because you do have control over this one.

OutOfHere• 5 months ago

A rise in blood bicarbonate, even if in the normal range, particularly at the upper end of normal, is still dangerous at times. The problem is that it has an effect of diminishing extracellular potassium which leads to spikes in heart rate, risking a cardiac emergency. I have witnessed it first hand.

piloto_ciego4• 5 months ago

This is actually my theory on why we're behaving so stupidly right now en masse.

I'm sure there's other papers out there, but this is the first one for this post: https://www.sciencedirect.com/science/article/pii/S036013232...

Anyway, CO2 levels rise on planet earth, which cause indoor levels to rise too. As it turns out, because of ventilation and such, indoor levels are always a bit higher than outdoor levels. We cross some critical threshold and it gets really hard for us to take on complex cognitive tasks and make good decisions. This effects everyone equally more or less a bit worse at planning, a bit worse at solving problems, a bit worse and making critical decisions.

In the long run, planners make worse decisions, governments make work decisions, voters make worse decisions, students perform more poorly... you get the picture. Over 20 or 30 years these bad decisions start to ramp up into meaningful impacts on the world. At risk of "post hoc ergo proctor hoc"-ing myself, the tipping point for this being somewhere close to 400ppm would make a lot of sense, because people seem to be noticeably dumber some time after 2014 ish? Hard to really pin it down though, but once CO2 levels started to routinely crest over that 1000ppm it seems to me that the world started to get a lot crazier.

Like, we can blame it on one politician we don't like or another, or on bad economic forecasting, or on the schools, or on latent racism / sexism / whatever-ism. To be clear, those are all legitimate concerns, but at the end of the day we're just animals more or less stuck on this orb zipping through the cosmos and if we're suddenly unable to do high level reasoning as well wouldn't you expect to see an increase in "dumb ideas" being accepted?

chneu2• 5 months ago

Reminder that an individual can cut their emissions by a staggering amount by just not eating meat/dairy.

Depending on how much you consume, you can cut your emissions by 50%!

Regenerative ranching is a lie and is more based in "vibes" and "energies" than science. Making beef production 0.01% more efficient then increasing consumption does not help. Meat is a "status symbol" food based in excess, grass fed beef is just another excuse to use more resources on a good to show how much of a status symbol it is. Grass fed beef is not good for environment. That's nonsense. It's less efficient beef called green. It's more expensive so people can claim superiority for buying it.

Our ego, pride, heritage, and machismo are used to manipulate us into beating our chests and consuming more protein, cuz winners eat 1.2g protein per kg and go to the gym. See how our health is used to manipulate us and justify excessive consumption in the form of "health and fitness"? Our colonist/conquerer society is dead set on us consuming more and more. We gotta buy more funco pops to keep up with social media influencers.

At the current point, the ONLY thing that makes sense is to cut your excessive consumption. We arent removing anything from the environment at this point and "recycling" and "regeneration" are meaningless.

We've blown past every milestone of destruction we have. We consistently increase our emissions and consumption. We are not doing anything to stop this.

Reduce and sacrifice is all that matters right now. Soon, a lot of this won't be an option for people, it'll be forced on them because of our selfishness today.

Our kids and grandkids have every reason to blame us. We are finding, creating and using every excuse we can for why this isn't our fault as we bite into a cheap burger.

WorldMaker5• 5 months ago

Reminder that corporations spent a ton of money on propaganda to make us all believe individual sacrifices can have a noticeable impact when the largest offenders are all corporate. Even if everyone reduced their personal carbon footprint by avoiding meat/dairy and the industrial cattle farms mysteriously disappeared overnight, that's still a drop in the overall greenhouse gas emission problem. Also note that "everyone" is doing a lot of work in that sentence and also means collective effort is required to make the change noticeable/effective rather than individual efforts.

Collective action is what matters. Corporate regulation is what matters. An enhanced EPA with real enforcement powers (not just fines, but the ability to shut down companies and/or outright murder them; which is also a larger debate because right now Americans generally don't believe in corporate murder and think corporations have a right to indefinitely exist) is what is necessary.

It is because of our selfishness, but also our selfishness extends to not working together in enough solidarity and instead fingerpointing at individuals to "do their part, alone, and without support systems and systemic change". That's pretty selfish, too. We need systemic change. We need support systems. We need a government that prioritizes the environment and our collective health and well-being. We need companies to understand that ethics matter as much as profits and if they cannot find profits that are ethical, including and especially in relationship to their externalities like greenhouse gas emissions, then they do not deserve to make those profits and may not deserve to continue operation as a company.

qingcharles2• 5 months ago

Me in Europe: 5 different bins on 5 days of the week for all the different types of recycling.

Me in USA: insert John Travolta looking around meme consumer recycling is practically unheard of in large parts of the country.

tt243• 5 months ago

Why do the corporations pollute so much? Is it just for the love of the game?

alexk307• 5 months ago

In the reference period 1999->2020, the instruments used by NHANES to track this data changed at least 3 times, they don't account for other changes to the general population that increase bicarbonate levels in serum (i.e. Number of obese Americans rose by ~40% in the reference period [1]). I'm not entirely convinced that using a proxy for C02 levels that can be confounded by a multitude of other health conditions that are common in the American population is a good way of going about this.

[1] https://www.niddk.nih.gov/health-information/health-statisti...

bethekidyouwant• 5 months ago

How do you unconfound this from being inside in better sealed environments for longer periods now? Not even mentioned?

deeg• 5 months ago

I remember when I first saw an oxygen bar at a mall and thinking how stupid it was. Fools and their money...

But who's laughing now?

beeforpork• 5 months ago

And while we pump CO2 into the atmosphere, we also shrink the engines that could get it out again, like the rainforest in Brazil. Perfect optimisation!

(I don't want to shame Brazil, it's a global chain of problems. And other forests are decimated, too, like in Sweden and Estonia, for the demand of produce worldwide.)

Rising carbon dioxide levels now detected in human blood

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