In reference to iodized salt, you would die of salt overdose before there are ill effects from iodine.

What's stopping salt from having a much higher concentration of iodine than the normal advertised value?

e.g. manufacturing error such that a dangerous amount of iodine is accidentally added.

I benefit from a very robust set of regulatory controls ensuring that food products are as advertised and generally safe for me to consume?

'generally safe' implies that some small number of folks still suffer from excess iodine due to contamination, manufacturing errors, etc...

It's probably reasonable for 999 999 people to benefit in exchange for 1 person being very unlucky, but that's a different argument that needs to be made.

I guess the same mechanisms that stop manufactures accidentally adding poison to their product.

Which is nothing? There's a clearly non-zero rate of dangerous contamination in food products, in a market as large as the US, that nobody is able to fully prevent.

Simply never way anything and you'll be safe!

Like I mentioned to the other replier, a probabilistic argument is fine, and I would even agree it's reasonable for 999 999 people to benefit in exchange for 1 person being very unlucky, but that's a different argument that needs to be made.

And nobody, in this post at least, has made that argument, nor has anyone even linked to such.

Whats stopping non-iodine salt from being poisoned by Cadmium or mercury? You can make up imaginary risks for pretty much everything.