E525 (Potassium Hydroxide) is an alkaline inorganic chemical compound also called caustic potash, which is obtained by an electrolytic process from potassium chloride.
It appears as a white powder or whitish flakes.
What it is used for and where
Food
Ingredient included in the list of European food additives as E525 as a preservative, acidity regulator.
Medical
Potassium hydroxide is a strong alkaline agent known to dissolve keratin, effective for the treatment of genital warts and in the paediatric treatment of Molluscum contagiosum. It is used in dermatology as a diagnostic test to identify fungal elements in skin scrapings.
Cosmetics
It is a restricted ingredient as III/15a, 15d a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009
Buffering agent. It is an iingredient that can bring an alkaline or acid solution to a certain pH level and prevent it from changing, in practice a pH stabiliser that can effectively resist instability and pH change.
Cosmetic safety
The SCCS cosmetics expert committee considers potassium hydroxide to be safe for use as a callus softener/eliminator at a maximum concentration of 1.5% by weight. Other potential uses of potassium hydroxide in cosmetic products cannot be evaluated without further documentation. The safe use of cosmetic products containing free potassium hydroxide in concentrations of 0.5% and above depends on responsible risk management (warnings and broad indications for use) (1).
Other uses
- Tomato peeling
- Counteracting microorganisms associated with poultry processing
- Alkaline flow in glass production
- Chemical activator
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- Molecular Formula KOH or HKO
- Molecular Weight 56.106
- CAS 1310-58-3
- UNII WZH3C48M4T
- EC Number 215-181-3
