Recently, NASA and other space agencies were dealing with an epidemic of headaches and other performance problems among the crew of the International Space Station (ISS). They traced this epidemic to the cause of elevated carbon dioxide (CO2) levels on the station. Because of the technological challenges and resource demands of lowering CO2 levels, astronauts have been told they will just have to accept the elevated levels of CO2 and the consequences that come with them.
Carbon Dioxide Levels on the International Space Station
CO2 is the dominant gas we exhale when we breathe. It is generated in our body when we use oxygen (O2) to burn food for energy in our cells. With a relatively high number of people breathing a relatively small amount of air, CO2 levels on the ISS can go up considerably.
The ISS is designed to remove CO2 from the atmosphere. It has three atmosphere processors designed to remove CO2 from the air. However, with 6 crew members aboard the space station, the levels of CO2 on the ISS have increased, and regularly exceeded the 4 mm mercury (Hg) partial pressure. In attempting to lower the headache risk, scientists decided to target an average value of 4 mm Hg of CO2, which they predicted would be associated with a headache risk of 1.6% per week, down from 3.3%. This is more than ten times the level of CO2 we experience on Earth (0.3mm Hg), and is only an average. Current CO2 levels on the space station range from 1 mm HG to 9 mm Hg. In order to reduce the headache risk to 1%, they would have to drop CO2 levels to 2.5 mm Hg, and NASA determined that attaining levels below 3 mm Hg was impractical, so astronauts will just have to accept headaches as an occupational hazard (as many of the rest of us do, though we are more likely to suffer from TMJ headaches, which can be treated).
The Coming Headache Plague?
But, wait, you may ask, what about increasing CO2 levels on Earth? Will carbon emissions cause us all to suffer an increase in headaches? The answer is a qualified “yes.”
As noted above, the current CO2 levels on Earth are less than a tenth of what they are on the space station. Currently, CO2 levels on earth are growing by 0.7% per year. At this rate it will take us about 280 years to reach headache-inducing CO2 levels. Unfortunately, CO2 levels are actually increasing faster every year. From 2012-2013, CO2 levels increased by 0.4%. If the rate at which increases occur continue to increase, in ten years our level of increase would be not 0.7% per year, but 4% per year. At that rate, it will only take 55 years to reach headache-inducing CO2 levels, and would exceed the levels on the ISS in 66 years. So, from a headache standpoint, it certainly seems that we should try to at least keep CO2 increases from increasing.
If you’re experiencing jaw pain along with headaches, you may have TMJ. Call (303) 691-0267 at the TMJ Therapy & Sleep Center of Colorado to learn more.