Chemicals have their uses: mankind has contrived to survive through many ages despite a heedless addiction to sodium chloride.
Sodium chloride is used and results in industrial wastes during the manufacture of aluminium.
That would be the result of ingesting any commodity, be it a vitamin, good food, bad food, fluoride sodium chloride or anything else.
I understand the dog stood for some time in water, to which sodium chloride had been added, or, in other words, a little common salt.
The supernatant was discarded and the precipitate re-suspended in a saturated solution of magnesium sulphate, zinc sulphate or sodium chloride.
For most releases the desired density of the mixture in the cup was obtained using sodium chloride (common salt).
Saturated magnesium sulphate was found to be a more effective flotation solution than zinc sulphate and sodium chloride for recovering eggs from fox faecal samples.
They are necessary because salt is sodium chloride, and a posteriori because determining the identity takes some empirical work, that is, a discovery by science.