Is fluoride used in tanneries?

Fluoride is a mineral found in food, water, toothpaste etc. It strengthens tooth enamel

it is a supplement used to prevent cavities.

from wikipedia: "Tetrafluoromethane is sometimes used as a low temperature refrigerant. It is used in electronics microfabrication alone or in combination with oxygen as a plasma etchant for silicon,...

Used in the manufacture of hydrofluoric acid, as a reagent, catalyst, and fluorinating agent, and in the refining of uranium and the preparation of many fluorine compounds. Suggested links:...

Fluoride is designated a Class 2 poison by the EPA, an acute toxin worse than lead and almost as bad as arsenic. According to the National Cancer Institute it's a known carcinogen. Hydrofluorosilicic...