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Public Health
Expert opinion

Potassium hydroxide (KOH) as callosity softener/remover

Final Opinion


Publication date
27 March 2014
Scientific Committee on Consumer Safety (SCCS)


WG on Cosmetic Ingredients
SCCS members: U. Bernauer, P.J. Coenraads, G. Degen, M. Dusinska, D. Gawkrodger, W. Lilienblum, A. Luch, E. Nielsen (rapporteur), T. Platzek, S.C. Rastogi (chairman), C. Rousselle, J. van Benthem
External experts: I. White, V. Rogiers
Contact:SANTE-C2-SCCSatec [dot] europa [dot] eu (SANTE-C2-SCCS[at]ec[dot]europa[dot]eu)
On request from: European Commission
SCCS Number: SCCS/1527/14
Doi: 10.2772/56132
Adopted on: 27 March 2014

Conclusion of the opinion:

In addition to those uses already regulated by the Cosmetics Regulation (EC) n. 1223/2009, the SCCS is of the opinion that potassium hydroxide is safe for use as callosity softener/ remover with a concentration of maximum 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 from 0.5% depends on responsible risk management (warnings and extensive guidance for use).


SCCS, scientific opinion, Potassium hydroxide (KOH), Regulation 1223/2009, CAS 1310-58-3, EC 215-181-3

Opinion to be cited as:

SCCS (Scientific Committee on Consumer Safety), Opinion on Potassium hydroxide (KOH) as callosity softener/remover, 27 March 2014, SCCS/1527/14.