That's the first time I've heard about that theory about why wearing masks could be dangerous. Do you have a citation for that? I'd be very curious to read the study. Intuitively it seems like there's no way you could end up with a higher time integrated density of virions inside the mask than outside unless you put on the mask in a very contaminated area and then wore it into non-contaminated place. But maybe there's some mechanism I'm not thinking of?