Is the purity of soft water salt and sodium chloride in Ziliujing the highest?

Self-well soft water salt is currently the soft water salt with the highest sodium chloride purity on the market, reaching over 99.72%, and is of food grade. Our family has had a water softener for several years. Many brands of soft water salt were used. The soft water salt from Ziliu Well is being used now. Because the dosage is less than before, the purity must be very high, right?

But please tell me that the soft water salt from Ziliujing does not contain bromine. The ones with low content fully meet the standards, while other brands of soft water salt do not have bromine indicators.

Bromine is a very strong carcinogenic element