Whether any of this is harmful is pure guesswork and proven by no scientific stuudies.
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I think they cause kidney problems in animals.
PFAs in large amounts will probably cause problems in animals and humans. The question is what amount is harmful?
Nobody is feeding animals PFAs as part of their regular diet. It’s in submicroscopic amounts in water in various places.
We run into the precautionary principle with these trace chemicals. If they can be shown to cause problems at high doses, let’s ban them down to the traceable levels, which is often parts per trillion.
Anti chemical activists do this all the time.