Funny, but this almost certainly refers to Potassium Chloride, no?
Or any other halogen.
Potassium chloride is necessary for good health, but not always. It can further injure people on certain meds, and with certain health conditions, like kidney failure.
Salt is also necessary for life, but again, certain health issues can be impacted by too much of it.
Someone once told me that if you want healthier food, shop the outside isles of the store, skip the inner isles. Thats wheee the bad chemicals are.