bananapeel

Caustic Soda

SODIUM HYDROXIDE

Data confidence:High

Function

pH Adjuster, Buffering Agent

EWG Safety Score

8/10High concern

About this ingredient

Sodium hydroxide is a strong alkaline chemical used in cosmetics as a pH buffer and neutralizing agent to adjust formulations to safe, skin-compatible pH levels. In hair care and depilatory products, it breaks down keratin structures to remove hair. It requires careful dilution and formulation to prevent skin irritation and chemical burns.

Found in 1+ sunscreens