[cyphar]

Botulinum toxin (botox) doesn't kill most people in the standard dosage, but it is obviously toxic (it's in the name).

Paracetamol poisoning is fairly common, hypernutremia isn't. Don't get me wrong, I disagree with the original statement that paracetamol is toxic (with the implication that this is a reason not to use it in normal dosages). But it's definitely not harmless.

[naasking]

I agree it's not harmless, but strictly speaking this kind of phrase is meaningless because nothing is intrinsically harmless. Dosage dictates all harm.

Probably the closest to harmless you can get are the inert gasses, and even then they can cause harm by displacing oxygen to deadly levels.