I just searched with the terms “edible dead sea salt.” Yes, I got lots of hits, but in the text from those pages, the word “edible” seems to always have the word “not” in front of it.
Anyone here ever been to the Dead Sea? Floating in it is supposed to cure many ailments, and is also a pretty weird/fun experience as, of course, it is so much more boyant than ordinary sea water.
On the other hand There are large signs is several languages warning people not to try to swim and not to put their heads under. If they swallow any water they are advised to seek help immediately.