Aluminium chlorohydrate

Aluminium chlorohydrate is a group of specific aluminium salts having the general formula AlnCl(3n-m)(OH)m. It is used in cosmetics as an antiperspirant and as a coagulant in water purification.

Chemistry

In terms of their structures, the species formed by aluminium chlorohydrate are similar to those produced by aluminium hydroxide. Both materials are amorphous to X-rays and they are often termed as "polyaluminium" species. In water purification, this compound is preferred over aluminium sulfate because it forms a gel-like floc that can remove suspended material from water.

Applications

Antiperspirant

Aluminium chlorohydrate is the active ingredient in many antiperspirants, it functions by blocking the pores in the skin, thereby preventing sweat from reaching the surface. The blockage is temporary and is removed by the natural sloughing of the skin. It is one of the most common active ingredients in commercial antiperspirants.

Water purification

In water purification, aluminium chlorohydrate is used as a coagulant. It reacts with the alkalinity in the water to form an aluminium hydroxide gel. This gel can trap and then remove suspended material, bacteria, and viruses.

Safety

The safety of aluminium chlorohydrate has been discussed with respect to its use in antiperspirants. Some studies suggest a potential link between aluminium chlorohydrate and Alzheimer's disease and breast cancer, but these findings are controversial and not widely accepted.

See also

• Aluminium sulfate
• Antiperspirant
• Water purification