What it is
An anti-caking agent in table salt — the "cyanide" in the name scares people more than it should.
Why your biology objects
The cyanide is locked in a stable iron complex that doesn't release free cyanide under cooking or digestion — chemically inert and used at trace levels. Read it as a tell, not a toxin: it's there so refined salt pours, a long way from the sea or the mine.