Aluminum chlorohydrate (ACH) is a group of salts that are used as antiperspirants in personal care products. It refers to a class of water-soluble aluminum salts with the general formula AlnCl(3n-m)(OH)m. ACH is a white or pale yellow solid that is soluble in water. It is produced by reacting aluminum with hydrochloric acid, which results in the formation of a range of aluminum chlorohydrate compounds. It is used as an antiperspirant in cosmetics and as a coagulant in water purification.
This compound is preferred in some cases for water purification 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 (PAC) and polyaluminium chlorisulfate, which have a lower net charge than aluminium chlorohydrate. Furthermore, when compared to other aluminium and iron salts, the high degree of neutralization of the HCl results in a minimal impact on treated water pH.
Properties
- Appearance: white to yellowish, crystalline powder or solid.
- Solubility: soluble in water, but the solubility decreases as the aluminium content increases.
- pH: acidic, with a pH of around 4.0 to 4.4.
Application
Aluminum 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. It is also used as a coagulant in water and wastewater treatment processes to remove dissolved organic matter and colloidal particles present in suspension.
ACH is widely used as an active ingredient in antiperspirant products due to its ability to reduce the production of sweat. It works by forming a gel-like plug in the sweat glands, which reduces the amount of sweat that is released onto the skin.
While ACH is generally considered safe for use in personal care products, some concerns have been raised about its potential health effects. One concern is that ACH may be absorbed through the skin and accumulate in the body, potentially leading to health problems over time. However, research on this topic is ongoing and currently inconclusive.
Overall, ACH is an effective and widely used ingredient in antiperspirant products, but consumers should be aware of the potential health concerns associated with its use and consult with a healthcare professional if they have any questions or concerns.
Safety concerns
There have been concerns about the potential link between aluminium compounds and breast cancer or Alzheimer’s disease, but there is currently no conclusive evidence to support these claims. Nonetheless, some individuals may experience skin irritation or allergic reactions when using products containing ACH.