Ah, I see.

> primarily peracetic, or peroxyacetic acid, which is essentially a mixture of vinegar and hydrogen peroxide

The NPR should possibly hire a science editor. Peracetic acid is not a _mixture_ of vinegar and hydrogen peroxide, any more than water is a mixture of hydrogen and oxygen. It can be, though in practice is not, made by _combining_ them.

Anyway, same concern as chlorine from the EC’s point of view; it’s an attempt to clean up the problem after it is created, of dubious efficacy, whereas EC policy is to attempt to avoid creating it in the first place.