Atmospheric Carbon Dioxide Rises, Scientists Find Surprising Changes in Blood
The surge in atmospheric carbon dioxide is suspected to be starting to affect the human body. Recent research has identified chemical changes in the blood that appear to occur alongside rising concentrations of carbon dioxide in the atmosphere.
This finding is considered important, especially for children and adolescents. Because they are still growing, they are potentially exposed to higher concentrations of carbon dioxide throughout their lives.
In a study published in the journal Air Quality, Atmosphere and Health, researchers from The Kids Research Institute Australia, Curtin University, and The Australian National University (ANU) found changes in a number of chemical indicators in the blood as atmospheric carbon dioxide levels increased.
The researchers examined health data from the United States (US) population over approximately 20 years. They used data from the National Health and Nutrition Examination Survey (NHANES), analysing blood test results from around 7,000 people collected at two-year intervals from 1999 to 2020.
Since 1999, average serum bicarbonate levels have risen by 7 per cent. Bicarbonate is one of the blood markers closely related to carbon dioxide in the body. Over the same period, average calcium and phosphorus levels declined.
These biological trends occurred alongside an increase in atmospheric carbon dioxide levels, from around 369 parts per million (ppm) in 2000 to more than 420 ppm today. One of the researchers, Professor Alexander Larcombe, said the findings suggest the human body may have undergone adjustments to changes in atmospheric composition.
“What we are seeing is a gradual shift in blood chemistry that reflects the increase in atmospheric carbon dioxide, which is driving climate change,” Larcombe said, as quoted from Science Daily, Tuesday (25/8/2026).
Bicarbonate plays an important role in regulating the body’s acid-base balance. When carbon dioxide levels rise, the body can retain more bicarbonate to help keep blood pH stable.
Although this response helps maintain bodily equilibrium, sustaining it over the long term has the potential to produce physiological effects.
“If current trends continue, modelling shows that average bicarbonate levels could approach the upper limit of the currently accepted healthy range within 50 years, and calcium and phosphorus levels could also reach the lower limit of their healthy range by the end of this century,” Larcombe said.