A. Short answer: Not really.
Long answer: Inhaling *high* levels of carbon dioxide (CO2) (also called hypercapnia, or CO2 toxicity) can in fact cause health issues like headache, dizziness, confusion, and even suffocation. But the key word is *high.*
Few people are actually at risk of hypercapnia, whether they wear masks or not. Conditions like chronic obstructive pulmonary disease (COPD) and other lung diseases can cause high CO2 levels. Activities that increase the risk of hypercapnia include scuba diving and…..space flight!
The point is that while CO2 toxicity is real, the circumstances that lead to it are uncommon.
So why is this less of an issue with masks? CO2 and oxygen molecules are much smaller than the COVID-19 virus and will pass through the material of an N95 mask, as well as any other home-made mask. Doctors could not possibly perform surgery for hours on end if wearing a mask caused CO2 to rise to levels that would cause impairment!
Nevertheless, the extent to which a mask could cause milder symptoms like headaches can depend on what the mask is made of, how tightly it fits, how long it’s being worn, and whether or not a person has other pre-existing issues.
In one study that’s been used as evidence for why masks can cause health issues, 37% of healthcare workers in a hospital in China reported headaches after wearing an N95 mask, particularly if it was worn for >4 hours straight and if they had pre-existing headaches. But this also means that the majority (63%) reported no headaches from mask use.
Some tips:
1. The CDC specifically recommends use of cloth masks for the public. N95 masks are designed to protect healthcare workers, and should not be worn by the public.
2. Select a more breathable fabric like 100% cotton for your cloth mask vs. synthetic fabrics like polyester.
3. Check the fit: Make sure your mask covers your nose and mouth but feels loose, rather than too tight. Consider using adjustable ties rather than elastic straps which can be irritating for your ears.
4. Limit how long you wear a mask: the CDC recommends masks be primarily worn in “public settings where other social distancing measures are difficult to maintain.”
5. For individuals with pre-existing respiratory issues like COPD, breathing, even without a mask, is more difficult. Therefore, use more caution when wearing one.
Take-home point: mild health complaints associated with mask use can depend on the type of mask, the fit, the length of time wearing it, and the presence of pre-existing respiratory illnesses. But overall, there’s no evidence that wearing a cloth mask is harmful to your health.
