The most widely-known property of HF is its ability to dissolve glass. Hydrofluoric acid also attacks glazes, enamels, pottery, concrete, rubber, leather, and many metals and organic compounds. Upon reaction with metals, explosive hydrogen gas may be formed. Use and store HF in polyethylene, teflon, wax, or passivated steel vessels. Chronic exposure to fluoride, including fluoride-containing compounds other than HF, can cause tooth mottling and increased bone density.
Fluoride ions are acutely and chronically toxic.
Exposure to less concentrated solutions may have equally serious but delayed effects. Physiological Properties HF has poor warning properties . The odor threshold for humans is 3 ppm and irritation of mucous membranes begins at 5 ppm. If you can smell it, chances are the concentration is too high and immediate steps must be taken to lower it. Fluoride ions migrate through the body destroying tissue until lodging in the bones.