I'm no chemist and my "gut feel" is dr holmes-farley is right on.
above is from product data sheet.
looks like nacl (salt) can be up to 6% and magnesium chloride is greater than .5%. both of which should be no problem.
Calcium hydroxide is kalk and at high concentrations can be a problem which is why we drip it. But should not be a problem as lower concentrations.
Perhaps dr Homes-Farley can provide more insite but then the good dr probably checked this out already.