Atmospheric CO₂ Rise Shows Up in Human Blood

Researchers led by respiratory physiologist Alex Larcombe at The Kids Research Institute Australia and Philip Bierwith at Australian National University report that rising atmospheric CO2 may be altering human blood chemistry. Using the US National Health and Nutrition Examination Survey (about 7,000 participants every two years from 1999–2020), they found average blood bicarbonate levels increased 7% since 1999, tracking the rise in atmospheric CO2 from roughly 300 ppm historically to more than 420 ppm today. The study, published last month in Air Quality, Atmosphere and Health, also found blood calcium fell 2% and phosphorus about 7%, consistent with physiological buffering of increased acidity. Authors caution the analysis did not control for diet, medications, kidney function, obesity, or indoor CO2 exposure, and call for further confirmation.

Researchers led by respiratory physiologist Alex Larcombe at The Kids Research Institute Australia and Philip Bierwith of Australian National University report that rising atmospheric CO2 may be measurably shifting human blood chemistry. Using the US National Health and Nutrition Examination Survey (about 7,000 Americans sampled every two years from 1999–2020), they found average blood bicarbonate levels increased 7% since 1999, tracking the rise in atmospheric CO2 from roughly 300 ppm historically to more than 420 ppm today. The study, published last month in Air Quality, Atmosphere and Health, also found blood calcium fell 2% and phosphorus about 7%, consistent with buffering of increased acidity. Authors caution the analysis did not control for diet, medications, kidney function, obesity, or indoor CO2 exposure.

The article titled “Intensifying global heat threatens livability for younger and older adults” could not be accessed because the page displayed a Radware Bot Manager CAPTCHA and an error message instead of the story text. The only available details are the headline, a publisher contact link (ioppublishing.org/contacts/), and an incident identifier (c8ec5a39-cnvj-489e-8cd8-269042736a0a). Based on the headline alone, the piece appears to address how rising global temperatures may reduce livability, with particular risks for younger and older populations. However, no information is available on the study, authors, location, methods, dates, or quantitative findings, so specific claims and implications cannot be verified from the provided content.

Researchers from The Kids Research Institute Australia, Curtin University and the Australian National University report that rising atmospheric CO₂ is being reflected in human blood chemistry. In a study published February 27, 2026 in Air Quality, Atmosphere and Health, the team analyzed U.S. NHANES data from about 7,000 people every two years between 1999 and 2020. Average serum bicarbonate, a marker linked to CO₂ handling and acid–base balance, increased about 7% since 1999, while average calcium and phosphorus declined. Over the same period, atmospheric CO₂ rose from roughly 369 ppm (2000) to above 420 ppm today. Modeling suggests bicarbonate could approach the upper end of today’s healthy range within 50 years if trends continue, with potential implications for children and adolescents’ long-term exposure.

Researchers from The Kids Research Institute Australia, Curtin University and the Australian National University report that rising atmospheric CO₂ is being reflected in human blood chemistry. In a study published in Air Quality, Atmosphere and Health, the team analyzed U.S. National Health and Nutrition Examination Survey (NHANES) results from about 7,000 people every two years from 1999 to 2020. Average serum bicarbonate, a marker linked to CO₂ and acid–base regulation, increased about 7% since 1999, while average calcium and phosphorus declined. Over the same period, atmospheric CO₂ rose from roughly 369 ppm (2000) to above 420 ppm today. Modeling suggests bicarbonate could approach the upper end of today’s healthy range within 50 years if trends continue, with implications for long-term exposure in children.