Do face masks cause harmful levels of carbon dioxide in the air we breathe?

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Alejandro Perez

Since the start of the pandemic, face masks have become a part of our everyday life. Even with masks mandates loosening up, the CDC recommends using a face mask while indoors regardless of vaccination status. On occasion, you might hear someone voice a concern about potential detrimental effects of wearing a mask. At one point there was a discussion about levels of carbon dioxide inhalation with masks.  

Carbon dioxide is toxic at levels of 10 percent in the breathed air. Carbon dioxide, oxygen, and other gases easily pass through masks. The molecules are so small only a solid barrier would prevent their passage. 

Respiratory droplets that carry the COVID-19 virus are much larger than carbon dioxide molecules and cannot pass through the masks. Even while undergoing intensive exercise, face masks have been found to be completely safe with only a slight reduction in physical performance due to slight restriction of airflow. 

Doctors, nurses, and surgical technicians have long worn masks for extended periods of time during surgery, up to 18 hours without impairment and with no increase of carbon dioxide levels in their blood. 

Low levels of carbon dioxide are not always harmful. For example, carbonated drinks, which are fizzy due to carbon dioxide being released from the liquid, are completely safe to consume. The carbon dioxide levels in carbonated beverages are way too low to have an effect on our bodies, and the same can be said about face masks and the normal carbon dioxide concentration in our environment of 0.04 percent that we inhale and exhale.

The concept of face masks causing harmful inhalation of carbon dioxide runs counter to knowledge, experience, and common sense. The idea is harmful and stressful at a time when we do not need any additional stressors and we need to take action to limit the pandemic.  Wearing a face mask is safe and allows us to control the spread of the COVID-19 virus. For more information about the COVID-19 virus, visit the CDC website. Stay safe!

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