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.
In water purification, this compound is preferred in some cases because of its high charge, which makes it more effective at destabilizing and removing suspended materials than other aluminium salts such as aluminium sulfate, aluminium chloride and various forms of polyaluminium chloride and polyaluminium chlorisulfate, in which the aluminium structure results in a lower net charge than aluminium chlorohydrate. Further, the high degree of neutralization of the HCl results in minimal impact on treated water pH when compared to other aluminium and iron salts.
Aluminium chlorohydrate is one of the most common active ingredients in commercial antiperspirants. The variation most commonly used in deodorants and antiperspirants is Al2Cl(OH)5.
Aluminium chlorohydrate is also used as a coagulant in water and waste water treatment processes to remove dissolved organic matter and colloidal particles present in suspension.
The Food and Drug Administration considers the use of aluminium chlorohydrate in antiperspirants to be safe and it is permitted in concentrations up to 25%.
Studies have found only a negligible association between exposure to and long-term use of antiperspirants and Alzheimer's disease. There is no adequate evidence that exposure to aluminium in antiperspirants leads to progressive dementia and Alzheimer's disease.
Heather M. Snyder, the senior associate director of medical and scientific relations for the Alzheimer's Association, has stated, "There was a lot of research that looked at the link between Alzheimer's and aluminium, and there hasn't been any definitive evidence to suggest there is a link".
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