It's true that wearing a face mask can be uncomfortable at times: nose gets itchy, sweat collects and glasses fog up. But what's not true is that wearing a mask will give you carbon dioxide poisoning — one of the latest myths making its way around the internet.
"It is not a health risk; it's nowhere close to a risk,” says Travis Glenn, an associate professor of environmental health science and interim director of the Institute of Bioinformatics at the University of Georgia College of Public Health.
That's because the size of the oxygen molecules you breathe in and the carbon dioxide you breathe out “are substantially smaller than the virus that these masks are designed to trap,” explains Paul Pottinger, M.D., director of the Infectious Diseases and Tropical Medicine Clinic at the University of Washington Medical Center and professor of medicine and allergy and infectious diseases at the University of Washington. “So masks” — whether you make them or buy them — “are certainly safe from a respiratory or gas exchange perspective,” he adds.
And that's the case even if you wear your mask for a prolonged period of time, experts say. Pottinger points to doctors, nurses and other health care providers who wear medical-grade face masks for several hours while doing physically demanding work. It's common for people who work in construction to do the same. “They always wear their mask and none of them have died of carbon dioxide poisoning,” he says.