Rising Atmospheric CO2 Linked to Changes in Human Blood Chemistry

A study of U.S. health survey data from 1999‑2020 found that serum bicarbonate levels in the blood increased by about 7% while calcium and phosphorus concentrations fell. These trends closely paralleled the rise in atmospheric carbon dioxide, which grew from roughly 369 ppm to over 420 ppm during the same period.

The research, published in *Air Quality, Atmosphere & Health*, was conducted by scientists from Australia’s Curtin University, the Australian National University and The Kids Research Institute. The authors stress that the findings show a statistical association, not proof that higher CO₂ directly causes the blood changes, and they call for further investigation. They note that children and adolescents could be especially vulnerable if the trends continue.

While the results do not indicate an immediate medical emergency, they suggest that environmental monitoring might benefit from including biological markers alongside traditional climate metrics.