Those are dissolved solids in mg/L. Did you notice how the top 2 are literally table salt? Potassium Chloride is NuSalt (a type of table salt), Magnesium Chloride is valued in industry, Flouride is valued in industry (especially dental products).

The only things I see in this list that are problematic are the Strontium and the Bromide, and I'm sure somebody has a use for them. This is really just an entrepreneur's opportunity waiting to happen