Wear Your Face Mask And Savor Your CO2 Breath

This is truly a ‘duh’ moment.
When a healthy person wears a face mask, they continuously re-rebreathe a portion of the CO2 that comes out of their lungs. Of course, there are many different types of masks that vary in such CO2 concentration, but the principal remains the same. 
Breathing air that is too rich in CO2 has its own negative health effects!
Humans breathe in air that is approximately 20.95% oxygen, 78.09% nitrogen, 0.93% argon, and 0.04% (400 ppm) of carbon dioxide. U