Also known as: Lye, Caustic Soda, NaOH
Sodium hydroxide (lye) is used in cosmetic formulations as a pH adjuster to raise the pH of acidic formulations. It is used in tiny amounts and is fully neutralised in the final product. Essential for activating carbomer gels and adjusting the pH of serums and cleansers. Despite its caustic nature in concentrated form, it is safe in finished cosmetic products at appropriate concentrations.
Comedogenicity ratings are based on the rabbit ear assay model. Individual skin responses vary. See our article on comedogenicity ratings for context.
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