Health effects of increase in concentration of carbon dioxide in the atmosphere

[Cid_Yama]

http://www.alfaintek.com/assets/files/D_S_Robertson.pdf


Chronic Respiratory Carbon Dioxide Toxicity: a serious unapprehended health risk of climate change

The earth’s atmosphere has already reached CO2 levels that are outside the range breathed by humans throughout their evolution. As well, in earlier pre-primate epochs, elevated atmospheric CO2 has been found to be a cause of mass extinction events (Knoll et al. 1996)

Despite significant documentation of health issues due to CO2 in indoor environments, there is minimal awareness in the community. For spacecraft and submarines there are practical considerations that influence the recommended safe levels. Initial safe limits for the International Space Station were partly decided by engineering requirements (Cronyn et al. 2012) and submarine limits were balanced by the ability to surface and renew air quality. It seems that there has been little concern about low-level toxicity of CO2 because we have always had the back-up of an ambient atmosphere with low levels of CO2.

As mentioned previously the body compensates for high levels of CO2, through a combination of increased breathing, blood pH buffering, kidney and bone adaptations depending on the length of continuous exposure, until we can resume breathing lower levels of CO2.

One author suggests that blood pH would be reduced to dangerous levels, if there were no physiological compensation, at CO2 levels as low as about 430 ppm (Robertson 2006) implying that compensation would occur at this level. Ambient conditions may already be dangerously close to CO2 levels that will induce continuous body compensation. Moreover, there is strong evidence that, with chronic activity, compensation mechanisms can produce serious health issues such as kidney calcification and bone loss.

It is conceivable that these problems might appear at much lower levels of CO2 if compensation persisted for a much longer periods, for example living a whole lifetime in an elevated CO2 atmosphere of a climate changed future. In the final paper of the US Navy CO2 research program, Schaefer (1982) indicated that this issue had “become the concern of the Department of Energy and other US government agencies” although it appears to have been largely forgotten (or classified) since.

If allowed to persist, problems such as kidney calcification could lead to renal failure. In the extreme case lifespans could become shorter than the time required to reach reproductive age. This could threaten the viability of human and animal species without interventions such as the creation of artificial living environments.

The human species is already impaired in indoor environments and this is likely to get worse as rising outdoor levels of CO2 contribute to increased indoor concentrations. Furthermore, the incidence and prevalence of human kidney calcification (i.e. stones) is increasing globally with the rate highest for males (Romero et al. 2010). Although this may not be related, it is possible that rising office levels of CO2 is a contributing cause. As well there is evidence that CO2 toxicity contributes to a range of serious health issues including cancer, neurological diseases and sleep disorders, and is being experienced by individuals at the current ambient levels which are now 40% higher than pre-industrial levels. It seems likely that CO2 toxicity related to human-induced climate change is already having an unrecognised impact on population health.

From the evidence presented here, there appears to be current health impacts of rising CO2 levels and a significant risk of serious health issues arising in the human population at some time in this century.

 This means that most humans could at this time be experiencing persistent body compensation for acidosis effects resulting in serious health problems. The risk for human and animal population health in the near-future is extremely high and should be communicated since global awareness of this issue may enable a change in CO2 emission activities.

link

[opensheart]

OK, I can see health effects starting soon, lf not already.   I know I have increasing boughts of kidney stones.   And my Urology group started a separate phone channel just to deal with Kidney Stones. 

If the body might have to start permamently compensating, what ever that means,  at levels as low as 430.   And we are at 407, rising 3+ points a year.   We could be touching the 430 mark around 2025,  8 years from now.

Although it would be a couple more years before CO2 was always over 430.   And then it would depend on where on the planet you were.

But the below quote sounds like extrapolation to the nth degree.    I would like to see the evidence to back this claim up.

In the extreme case lifespans could become shorter than the time required to reach reproductive age. This could threaten the viability of human and animal species without interventions such as the creation of artificial living environments.

[DrTskoul]

From 2 yrs ago:

Exclusive: Elevated CO2 Levels Directly Affect Human Cognition, New Harvard Study Shows

[quoteIn a landmark public health finding, a new study from the Harvard School of Public Health finds that carbon dioxide (CO2) has a direct and negative impact on human cognition and decision-making. These impacts have been observed at CO2 levels that most Americans — and their children — are routinely exposed to today inside classrooms, offices, homes, planes, and cars.
Carbon dioxide levels are inevitably higher indoors than the baseline set by the outdoor air used for ventilation, a baseline that is rising at an accelerating rate thanks to human activity, especially the burning of fossil fuels. So this seminal research has equally great importance for climate policy, providing an entirely new public health impetus for keeping global CO2 levels as low as possible.][/quote]

[Laurent]

The article is not directly for CO2 but ...
More Than Half Of U.S. Medical Professionals Unite To Raise Alarm About Climate Change
http://www.huffingtonpost.com/entry/doctors-climate-change_us_58c85231e4b01c029d7717ed?ir=Green&utm_hp_ref=green

[ExplorerIII]

You can't stop CO2 in atmosphere. Its happening and the numbers will be higher every year. Lets say around 20 years ago was no a big problem with CO2. There are more planes cars( the worst one is the really old one), factories, mines. Those number will rise every year. Politics saying that something has to be done, but nothing is happening. They just talking. There is nothing we can do as a little people.

[MrVisible]

Mouse Lung Structure and Function after Long-Term Exposure to an Atmospheric Carbon Dioxide Level Predicted by Climate Change Modeling

Our data suggest that, in this mouse model, the period in which the lung is undergoing rapid growth and alveolarization is particularly important. Regardless, these data suggest that moderate elevations in atmospheric CO2 cannot be dismissed as insignificant in terms of their direct effects on health. Our data provide the rationale for further exploration of this phenotype. Future research is needed to assess whether long-term exposure to moderately increased CO2 also negatively impacts other organs that have previously been shown to be impacted by short-term, high-level CO2 exposure (e.g., the brain, kidneys, and bones). It is our opinion that with atmospheric CO2 increasing 2–3 ppm/y, it will not be long until a level is reached that is directly detrimental to human health. Thus, continued research in this area and increased effort in curbing CO2 emissions are both urgently required.

https://ehp.niehs.nih.gov/doi/10.1289/EHP7305

[The Walrus]

OK, I can see health effects starting soon, lf not already.   I know I have increasing boughts of kidney stones.   And my Urology group started a separate phone channel just to deal with Kidney Stones. 

If the body might have to start permamently compensating, what ever that means,  at levels as low as 430.   And we are at 407, rising 3+ points a year.   We could be touching the 430 mark around 2025,  8 years from now.

Although it would be a couple more years before CO2 was always over 430.   And then it would depend on where on the planet you were.

But the below quote sounds like extrapolation to the nth degree.    I would like to see the evidence to back this claim up.

In the extreme case lifespans could become shorter than the time required to reach reproductive age. This could threaten the viability of human and animal species without interventions such as the creation of artificial living environments.

Most studies have found no significant health effects below 10,000 ppm.  Erring on the side of caution, OSHA has set the maximum workplace concentration at 5,000 ppm.  The major issue appears to be reduced oxygen concentrations.  As long as atmospheric oxygen does not decrease (and there is no evidence that it will), any increase in carbon dioxide will have no harmful biological effects.

[oren]

Workplace CO2 does not cover the case of lung growth discussed in the preceding article.
Besides, I expect most readers know better than to fully trust your nice summary of "most studies" with no supporting evidence.
A 30-sec search brought this up, for example (from 2019):

https://airqualitynews.com/2019/07/10/co2-affects-human-health-at-lower-levels-than-previously-thought/

CO2 affects human health at lower levels than previously thought

Exposure to carbon dioxide (CO2) poses direct risks to human health at lower levels than previously thought, research has found.

Reviewing current studies on the subject, American academics concluded that exposure to ambient CO2 in indoor environments can have harmful effects on the human body at much lower levels, causing health problems such as inflammation, reduced cognitive performance and kidney and bone problems.

They found these health problems can be caused by exposure to CO2 levels as low as 1,000 parts per million (ppm) — a far lower limit than the 5,000 ppm level that had been widely accepted, researchers said.

The findings, published in the journal Nature Sustainability, sum up a growing body of research into CO2’s health effects which have to date been less explored than the effects of particulate matter (PM2.5) or nitrogen oxide (NOx).

‘This early evidence indicates potential health risks at CO2 exposures as low as 1,000 ppm–a threshold that is already exceeded in many indoor environments with increased room occupancy and reduced building ventilation rates,’ the study summarised.

Those behind the research looked at a total of 18 studies into human exposure to CO2, as well as CO2’s health effects on both humans and animals.

The researchers cited mounting evidence that CO2 levels as low as 1,000ppm can cause health problems, even if people are only exposed to them for an hour or two.

They found that CO2 levels exceeding 1,000ppm have already been observed in crowded and poorly ventilated rooms such as classrooms, offices and bedrooms as well as air-conditioned public transport and planes — all places where humans can spend several hours at a time.

Collating the findings of numerous studies, the academics summarised that acute exposure to high CO2 levels can have ‘adverse health outcomes’, citing studies which observed inflammation and reduced cognitive performance above 1,000ppm.

Chronic exposure to levels between 2,000ppm and 3,000ppm can have even worse impacts as this was linked to effects including kidney calcification and bone demineralisation.

The team behind the study warned that human CO2 exposure may be a growing problem in the coming years as projections suggest that by 2100 outdoor CO2 levels in some cities could exceed 1,000ppm for parts of the year.

‘Continuous exposure to increased atmospheric CO2 could be an overlooked stressor of the modern and/or future environment,’ the study suggested.

The researchers concluded by saying further research is needed to find ways to mitigate exposure to indoor CO2, especially for children and vulnerable people, and to fully understand its potential health effects.

[The Walrus]

Workplace CO2 does not cover the case of lung growth discussed in the preceding article.
Besides, I expect most readers know better than to fully trust your nice summary of "most studies" with no supporting evidence.

I did not realize that common knowledge required evidence.

Even your article states the 5,000 ppm level that had been widely accepted.

[The Walrus]

Workplace CO2 does not cover the case of lung growth discussed in the preceding article.
Besides, I expect most readers know better than to fully trust your nice summary of "most studies" with no supporting evidence.
A 30-sec search brought this up, for example (from 2019):

https://airqualitynews.com/2019/07/10/co2-affects-human-health-at-lower-levels-than-previously-thought/

CO2 affects human health at lower levels than previously thought

Exposure to carbon dioxide (CO2) poses direct risks to human health at lower levels than previously thought, research has found.

Reviewing current studies on the subject, American academics concluded that exposure to ambient CO2 in indoor environments can have harmful effects on the human body at much lower levels, causing health problems such as inflammation, reduced cognitive performance and kidney and bone problems.

They found these health problems can be caused by exposure to CO2 levels as low as 1,000 parts per million (ppm) — a far lower limit than the 5,000 ppm level that had been widely accepted, researchers said.

The findings, published in the journal Nature Sustainability, sum up a growing body of research into CO2’s health effects which have to date been less explored than the effects of particulate matter (PM2.5) or nitrogen oxide (NOx).

‘This early evidence indicates potential health risks at CO2 exposures as low as 1,000 ppm–a threshold that is already exceeded in many indoor environments with increased room occupancy and reduced building ventilation rates,’ the study summarised.

Those behind the research looked at a total of 18 studies into human exposure to CO2, as well as CO2’s health effects on both humans and animals.

The researchers cited mounting evidence that CO2 levels as low as 1,000ppm can cause health problems, even if people are only exposed to them for an hour or two.

They found that CO2 levels exceeding 1,000ppm have already been observed in crowded and poorly ventilated rooms such as classrooms, offices and bedrooms as well as air-conditioned public transport and planes — all places where humans can spend several hours at a time.

Collating the findings of numerous studies, the academics summarised that acute exposure to high CO2 levels can have ‘adverse health outcomes’, citing studies which observed inflammation and reduced cognitive performance above 1,000ppm.

Chronic exposure to levels between 2,000ppm and 3,000ppm can have even worse impacts as this was linked to effects including kidney calcification and bone demineralisation.

The team behind the study warned that human CO2 exposure may be a growing problem in the coming years as projections suggest that by 2100 outdoor CO2 levels in some cities could exceed 1,000ppm for parts of the year.

‘Continuous exposure to increased atmospheric CO2 could be an overlooked stressor of the modern and/or future environment,’ the study suggested.

The researchers concluded by saying further research is needed to find ways to mitigate exposure to indoor CO2, especially for children and vulnerable people, and to fully understand its potential health effects.

Summarizing your article:

Inflammation:  "exposure to 3,000 ppm might induce mild inflammation of the nasal cavity in humans"

Cognitive effects:  "Two recent reviews concluded that environmentally relevant elevations in CO2 may directly affect higher-level cognitive performance, including decision-making and problem resolution."  Conversely, "three studies have reported non-significant results. found no significant reductions in cognitive performance in simple and moderately difficult tasks for 255 min exposures up to 3,000 ppm."

Conclusion:

"Emerging evidence supports the possibility that CO2 (at concentrations <5,000 ppm) poses direct risks to human health."

In essence, they conclude that many of these conditions may pose increased health risks under increased CO2 concentrations, mostly above 1000 ppm.

[oren]

In essence, they conclude that many of these conditions may pose increased health risks under increased CO2 concentrations, mostly above 1000 ppm.

And yet, true to the strategy of minimizing any and all negative effects, a few posts ago you wrote confidently:

Most studies have found no significant health effects below 10,000 ppm.  Erring on the side of caution, OSHA has set the maximum workplace concentration at 5,000 ppm.  The major issue appears to be reduced oxygen concentrations.  As long as atmospheric oxygen does not decrease (and there is no evidence that it will), any increase in carbon dioxide will have no harmful biological effects.

The reality is that where there are uncertain risks, prudence dictates not to write them off out of hand, but to treat them with respect and to be aware that some of these risks will actually materialize, on a statistical basis.

[The Walrus]

In essence, they conclude that many of these conditions may pose increased health risks under increased CO2 concentrations, mostly above 1000 ppm.

And yet, true to the strategy of minimizing any and all negative effects, a few posts ago you wrote confidently:

Most studies have found no significant health effects below 10,000 ppm.  Erring on the side of caution, OSHA has set the maximum workplace concentration at 5,000 ppm.  The major issue appears to be reduced oxygen concentrations.  As long as atmospheric oxygen does not decrease (and there is no evidence that it will), any increase in carbon dioxide will have no harmful biological effects.

The reality is that where there are uncertain risks, prudence dictates not to write them off out of hand, but to treat them with respect and to be aware that some of these risks will actually materialize, on a statistical basis.

The reason they are uncertain, is that evidence is lacking to show that a risk actually exists.  An abundance of evidence exists to state that 10,000 ppm leads to health issues.  Many of the studies referred to in the preceding article mention the most vulnerable (Young, old, sick, etc.) are susceptible to health risks at lower concentrations of CO2.  By contrast, detrimental health effects were not found in submariners and astronauts routinely exposed to levels of 5,000 ppm.

[Aluminium]

If something affects all humans in a similar way, extremely small probability becomes important. 0.0001% per year is nearly nothing for one and even may be hard to discover. However, it's enough to affect several times more people than members of this forum.

[kassy]

And of course the first article discusses specific risks:

Objectives:

In this study we aimed to assess the respiratory structure and function effects of long-term exposure to 890 ppmCO2 from preconception to adulthood using a mouse model.

Methods:
We exposed mice to CO2 (∼890 ppm) from prepregnancy, through the in utero and early life periods, until 3 months of age, at which point we assessed respiratory function using the forced oscillation technique, and lung structure.

Results:
CO2 exposure resulted in a range of respiratory impairments, particularly in female mice, including higher tissue elastance, longer chord length, and lower lung compliance. Importantly, we also assessed the lung function of the dams that gave birth to our experimental subjects. Even though these mice had been exposed to the same level of increased CO2 for a similar amount of time (∼8wk), we measured no impairments in lung function. This suggests that the early life period, when lungs are undergoing rapid growth and development, is particularly sensitive to CO2.

...

Although the acute, toxic effects of exposure to very high levels of CO2 (i.e., >100,000 ppm) are well known (Langford 2005; Scott et al. 2009), the potential impacts of prolonged exposure to levels predicted by climate change models are vague. The sparse research in this broad area includes studies aimed at understanding the effects of exposure to elevated CO2 in poorly ventilated classrooms/offices (Bakó-Biró et al. 2012; Lu et al. 2015; Muscatiello et al. 2015), submarines (Rodeheffer et al. 2018), and spacecraft (Law et al. 2010; James et al. 2011; Cronyn et al. 2012; Hughson et al. 2016) as well as small mammal laboratory studies aimed at understanding CO2-induced physiological changes (Schaefer 1982; Wade et al. 2000; Kiray et al. 2014; Martrette et al. 2017). Many of these studies have been succinctly summarized in a recent review (Jacobson et al. 2019).

Importantly, the vast majority of previous research in this area exposes humans or experimental animals (generally mice, rats, or guinea pigs) to levels of CO2 in excess of that predicted by climate change models (i.e., >1,000 ppm) for relatively short durations (i.e., hours to a few months). They do not extend to the in utero/early life periods when lung growth and development are rapidly occurring. Furthermore, controlled human exposure studies and laboratory studies are generally conducted in young, healthy adults who are likely to be the most able to cope with such exposure (Rice 2004). These previous studies show that exposure to CO2 between 1,000 and 5,000 ppm for hours to months can result in a range of adverse health effects, including inflammation (Schneberger et al. 2017; Thom et al. 2017a, 2017b) and cognitive impairment (Kajtár and Herczeg 2012; Satish et al. 2012; Allen et al. 2016; Snow et al. 2019), with some effects manifesting after as little as a few hours of exposure. As the duration of exposure increases to weeks or months, kidney calcification, bone demineralization (Schaefer et al. 1979; Schaefer 1982) and a range of behavioral changes have been measured (Kiray et al. 2014; Martrette et al. 2017).

To the best of our knowledge, there are no previous studies in which experimental subjects were exposed from preconception to adulthood to the levels of CO2 that are realistically possible in the near future (i.e., 600 to 900 ppm). This context is critical for the multifactorial implications of the current CO2 emission rates continuing. Here, we establish the first mammalian model of long-term exposure to ambient CO2 at a level predicted by climate modeling that incorporates the period from preconception to adulthood. We continually exposed mice for this period to ∼890 ppmCO2 and then assessed their respiratory structure and function. We focused on respiratory structure and function given that the lungs are the initial site for CO2 exposure and that they play a critical role in maintaining the body’s acid-base balance (Seifter and Chang 2017). It is thus likely that if any organ is going to be impacted by moderately increased CO2, it would be the lungs. We also assessed the lung function of the dams, which were exposed to ∼890 ppmCO2 for approximately the same duration, although they started exposure as adults.

And it discusses all we are discussing here with links.

Really short version: This research shows there is adverse effects at levels of 890 ppm because of exposure in early development.

Personally i think that the acute climate effects at 890 ppm will be a much bigger problem so this research is mostly interesting.

[The Walrus]

Personally i think that the acute climate effects at 890 ppm will be a much bigger problem so this research is mostly interesting.

Personally, I believe the opposite.  Namely that acute climate effects at 890 ppm will be a nonissue regarding health issues in humans.  A detrimental effect on mice may be a bonus.  Extending their results to humans is questionabe.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2746847/

[trm1958]

Personally i think that the acute climate effects at 890 ppm will be a much bigger problem so this research is mostly interesting.

Personally, I believe the opposite.  Namely that acute climate effects at 890 ppm will be a nonissue regarding health issues in humans.  A detrimental effect on mice may be a bonus.  Extending their results to humans is questionabe.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2746847/

I think he means more like Sea Level Rise, increased droughts damaging food production, stronger storms, et. al. rather than "health issues".

[The Walrus]

Personally i think that the acute climate effects at 890 ppm will be a much bigger problem so this research is mostly interesting.

Personally, I believe the opposite.  Namely that acute climate effects at 890 ppm will be a nonissue regarding health issues in humans.  A detrimental effect on mice may be a bonus.  Extending their results to humans is questionabe.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2746847/

I think he means more like Sea Level Rise, increased droughts damaging food production, stronger storms, et. al. rather than "health issues".

Substituting any of those for health issues seems odd, but whatever.

[kassy]

The mouse model is a good enough fit for these type of studies. The link you provided discusses different ones with different problems. Many claims related to medicine are way more specific.

The acute climate effects are things like the average temperature on Earth when we get to 890 ppm. Of course this is a rather vague measure but that should need some more decades of ignoring the problem or a really big climate feedback problem. The average global temperature should be much more problematic under such a scenario because all areas that are now marginal are already unlivable by that time and all the others decline too.

And yes at those values you will be at the other end of the BOE and much more ice will have melted off Iceland and Antarctica so most of our coasts will be in danger. This also includes salt water intrusion into all rivers and coastlands.

These results are interesting but not that important because other things will happen first.

[The Walrus]

The mouse model is a good enough fit for these type of studies. The link you provided discusses different ones with different problems. Many claims related to medicine are way more specific.

The acute climate effects are things like the average temperature on Earth when we get to 890 ppm. Of course this is a rather vague measure but that should need some more decades of ignoring the problem or a really big climate feedback problem. The average global temperature should be much more problematic under such a scenario because all areas that are now marginal are already unlivable by that time and all the others decline too.

And yes at those values you will be at the other end of the BOE and much more ice will have melted off Iceland and Antarctica so most of our coasts will be in danger. This also includes salt water intrusion into all rivers and coastlands.

These results are interesting but not that important because other things will happen first.

I agree.  Many other, more dire, consequences will occur before we reach this level.