if it were a significant health concern it is likely this would have been found out by those countries
There are tons of ordinary industrial/commercial practices that are harmful, but the harm is not obvious enough to be immediately noticed, or there's some other interest (classically, the interests of capital) that acts to prevent an honest investigation.
Not saying that's necessarily the case here; only that we definitely don't live in a world where significant health concerns are noticed promptly.
Well, it's both. But I'm not really talking about how to characterize mask wearing -- I'm saying that we have tons of examples of harmful practices (many of which happen to be industrial/commercial practices) that are not immediately recognized as such.
There are tons of ordinary industrial/commercial practices that are harmful, but the harm is not obvious enough to be immediately noticed, or there's some other interest (classically, the interests of capital) that acts to prevent an honest investigation.
Not saying that's necessarily the case here; only that we definitely don't live in a world where significant health concerns are noticed promptly.
This isn't an industrial/commercial practice, though, but a widespread social one.
Well, it's both. But I'm not really talking about how to characterize mask wearing -- I'm saying that we have tons of examples of harmful practices (many of which happen to be industrial/commercial practices) that are not immediately recognized as such.