Run screaming: Rising CO2 has been detected in human blood!

Jo Nova
joannenova.com.au
Tue, 03 Mar 2026 04:22 UTC

© CC0 Public Domain

The one-eyed science monster is here again to scare teenage girlies

No one is funded to poke holes in the CO2-octopus, so researchers can follow a silly idea for a long time. In a normal world someone would have scoffed and squashed this horror show in the tea room.

It is yet another meaningless correlation pretending to be a dangerous trend. Supposedly rising levels of carbon dioxide in the air around us is tainting our very blood, causing a public health crisis. Atmospheric CO2 is "higher than anything humans ever experienced" says Dr Phil Bierwirth, worried that current CO2 levels are beyond what we evolved to deal with, and 100% wrong.

Poor Dr Bierworth obviously doesn't realize that even though atmospheric CO2 has risen from 320ppm to 420ppm, normal indoor CO2 levels are 500 to 1,000 ppm, and the air we breathe out is 40,000ppm.

We don't need a quarter century to raise our blood CO2 levels — we can hold our breath and get there in sixty seconds.

Or we just need to go jogging.

Since he is a retired environmental geoscientist, it was cruel to set him up to fail so badly on what is a beginner medical question.

Rising carbon dioxide levels now detected in human blood

— Phys Org

Rising carbon dioxide levels are being detected within the human body, with new research warning a key blood marker for the gas could near its healthy limit within decades if current trends continue. The findings are especially relevant for children and adolescents, whose developing bodies will experience the longest cumulative exposure to rising atmospheric CO₂.

Using data from the U.S. National Health and Nutrition Examination Survey (NHANES), the team examined blood results from around 7,000 people every two years between 1999 and 2020.

Average levels of serum bicarbonate — a marker closely linked to carbon dioxide in the body — have risen by approximately 7% since 1999. Over the same period, average calcium and phosphorus levels have declined.

So many travesties of correlation in modern science use the term "mirror":

These changes mirror the rise in atmospheric CO₂, which has increased from about 369 parts per million (ppm) in 2000 to more than 420 ppm today.

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.

"It appears we are adapted to a range of CO₂ in the air that may now have been surpassed.

"As CO₂ in the air is now higher than humans have ever experienced, it appears to be building up in our bodies. Maybe we can never adapt such that it is vitally important to limit atmospheric levels of CO₂."

We not only evolved to deal with high levels of CO2, it is an important signaling mechanism in our blood — high CO2 levels tell red blood cells to give up their oxygen. It's how our blood gets oxygen to the cells that need it the most.

Whole health movements have been built upon raising the CO2 levels in our blood — like the Buteyko breathing or the Alexander technique — both used to reduce asthma.

If bicarbonate levels are slowly rising in blood perhaps it might be because there is more time spend indoors, less sunlight, poor breathing techniques, poor fitness levels, or more people with sleep apnea?

The obsession with energy efficiency means air flow indoors is more restricted than ever and thus we probably sleep in rooms with higher levels of CO2 than we did 30 years ago.

Whatever it is, modern witchdoctors will try to reduce blood bicarbonate levels with windmills.

UPDATE: CO2 dissolves in blood with the equilibrium reaction:

CO₂ + H₂O ⇄ H₂CO₃ ⇄ HCO₃^- + H⁺

If you hyper or hypoventilate for a few minutes it is possible to shift the direction of the flow here and even change blood pH. The pace of breathing, and the shallowness or depth will change the bicarbonate levels (HCO3-).

Check out the title of the paper! A 'potentially toxic atmosphere within 50 years!' It could only be written by zealots living in a crazy bubble.

As Dr Faustus remarks below, most of the CO2 in our blood is created by our metabolisms as we burn fats and sugars. A small rise in the air around us is irrelevant.

REFERENCE

Alexander N. Larcombe et al, Carbon dioxide overload, detected in human blood, suggests a potentially toxic atmosphere within 50 years, Air Quality, Atmosphere & Health (2026). DOI: 10.1007/s11869-026-01918-5