Silica gel is also used as cat litter[4], by itself or in combination with more traditional materials, such as clays including bentonite. It is trackless and virtually odorless. Silica in this form can be a cost effective way for retail consumers to easily purchase silica gel for application in such things as keeping tools rust free in damp environments, long term storage, and preservation of dried food for long term storage.
[edit] Hazards
Silica gel is non-toxic, non-flammable, and non-reactive and stable with ordinary usage. It will react with hydrogen fluoride, fluorine, oxygen difluoride, chlorine trifluoride, strong acids, strong bases, and oxidizers[5]. Silica gel is irritating to the respiratory tract, may cause irritation of the digestive tract, and dust from the beads may cause irritation to the skin and eyes, so precautions should be taken [6]. Some of the beads may be doped with a moisture indicator, such as cobalt(II) chloride, which is toxic and may be carcinogenic. Cobalt (II) chloride is deep blue when dry (anhydrous) and pink when moist (hydrated).
Crystalline silica dust can cause silicosis but synthetic amorphous silica gel is non-friable, and so does not cause silicosis