Masks may be uncomfortable, but not harmful

DEAR DR. ROACH » I am an 85-year-old working 20+ hours a week in retail. I have just returned to work after being furloughed because of the pandemic. My associates and I are required to wear masks, averaging seven hours daily. We feel as if our breathing is being compromised, as we are breathing in our own air, with no outside fresh air. Our masks get damp inside and some masks show the wearer to be inhaling the fabric itself as they breathe in. Is this safe? Are our lungs safe? Thank you for any reassurance you can offer.

— P.L.

DEAR READER » Wearing a mask for a prolonged time can be uncomfortable, but not dangerous. I have seen a lot of misinformation about supposed dangers of mask wearing, so I am glad you wrote.

There is a space between your face and the mask that will be filled with exhaled air. Exhaled air has more carbon dioxide and less oxygen than fresh air. However, the amount of that air is relatively small compared with the amount of air you breathe in, so you get a little exhaled air and a lot of fresh air — the space in your nostrils and upper airways have the same issue. Your lungs will compensate for the mask by breathing just a little deeper without you being consciously aware of it.

Surgeons wear face masks for many hours without problems, and numerous recent studies have shown no drop in oxygen levels nor increase in carbon dioxide levels associated with masks.

When health providers see patients suspected of having coronavirus, we wear an N95 mask, a surgical mask on top, and a face shield. This provides the most protection, which is especially necessary when performing procedures on people with COVID-19. A cloth face mask protects you to some extent, but it protects the people you are around to a much greater extent, because the virus is mostly on large droplets. These get filtered and trapped by the mask. If everyone wore a cloth mask all the time when in contact with others, the rate of transmission would plummet.

DR. ROACH WRITES » A recent column on getting routine urine analyses generated a surprising amount of mail. One important point that I didn’t include in my column: Some doctors obtain urine samples on everybody, but don’t run the analysis on them unless there is a reason to after seeing the provider. This way, they can be sure that a sample is available if needed. This seems reasonable, yet the office staff should be able to articulate that to the patients, to reassure their concerns about overordering of tests and charging for unnecessary tests.

Contact Dr. Roach at ToYourGoodHealth@med. cornell.edu.