A concerning trend is emerging as researchers detect rising levels of carbon dioxide (CO2) within the human body, mirroring the increasing CO2 concentrations in the atmosphere. A new Australian study indicates that a key blood marker, serum bicarbonate, is steadily climbing and could approach unhealthy levels within decades if current trends continue. This finding raises questions about the long-term physiological impacts of a changing climate on human health, particularly for younger generations.
The research, published in Air Quality, Atmosphere and Health, highlights a subtle but significant shift in human blood chemistry over the past two decades. Understanding the implications of rising atmospheric CO2 is crucial, and this study suggests the human body is already responding to these changes. The focus on serum bicarbonate levels – a marker directly linked to CO2 in the blood – provides a new lens through which to assess the biological consequences of climate change.
Researchers from the Kids Research Institute Australia, Curtin University, and the Australian National University analyzed data from over 7,000 individuals in the United States between 1999 and 2020. They observed a roughly 7 percent increase in serum bicarbonate levels during this period, a change that closely tracked the documented rise in atmospheric CO2. Concurrently, the study noted decreases in blood levels of calcium and phosphorus. These shifts, while currently within the accepted healthy range for most individuals, are prompting concern among scientists.
“These findings suggest the human body is already physiologically compensating for increasing atmospheric CO2,” explained Associate Professor Alexander Larcombe, lead author of the study at The Kids. “If current trends continue, our modelling indicates average bicarbonate levels could approach the upper limit of today’s accepted healthy range within 50 years.” This doesn’t necessarily mean immediate health crises, but it signals a potential strain on the body’s regulatory systems.
A dense fog envelops the Sydney skyline on August 5, 2025. Atmospheric CO2 levels are a contributing factor to climate change and, according to new research, may be impacting human blood chemistry. (PHOTO / AP)
Impact on Children and Adolescents
The study emphasizes the particular vulnerability of children and adolescents. Because their bodies are still developing, they will experience a longer cumulative exposure to elevated atmospheric CO2 levels. This prolonged exposure could have more significant and lasting effects on their physiological systems. Researchers are particularly interested in understanding how these changes might affect bone development and overall metabolic function. The World Health Organization (WHO) recognizes children as disproportionately vulnerable to the health impacts of climate change.
How the Body Compensates
Serum bicarbonate plays a crucial role in maintaining the body’s pH balance. As atmospheric CO2 increases, the body attempts to regulate this balance by increasing bicarbonate levels. However, this compensatory mechanism isn’t without potential consequences. The observed decreases in calcium and phosphorus suggest the body may be drawing on these minerals to maintain pH stability, potentially impacting bone health and other physiological processes. Further research is needed to fully understand these complex interactions.
The Need for Biomarker Tracking
The researchers advocate for a more comprehensive approach to monitoring the health impacts of climate change. They urge the integration of atmospheric composition data with population-level biomarker tracking, alongside traditional climate indicators. This holistic approach would provide a more accurate and nuanced understanding of how environmental changes are affecting human biology. The Centers for Disease Control and Prevention (CDC) likewise emphasizes the importance of tracking climate-related health impacts.
This study isn’t about predicting immediate health crises, but rather about identifying subtle shifts that could have long-term consequences. It underscores the interconnectedness of the environment and human health, and the need for proactive monitoring and research. The findings highlight the importance of continued efforts to mitigate CO2 emissions and protect public health in a changing climate.
Looking ahead, continued monitoring of both atmospheric CO2 levels and key biomarkers like serum bicarbonate will be essential. Researchers plan to expand their studies to include more diverse populations and investigate the specific mechanisms by which rising CO2 affects human physiology. Understanding these processes is crucial for developing strategies to protect public health in the face of ongoing climate change.
What are your thoughts on the potential long-term health impacts of rising CO2 levels? Share your comments below, and please share this article with your network to raise awareness about this important issue.
Disclaimer: This article provides informational content about health and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider for any questions you may have regarding your health.
