Authority source
Safety basis: NIOSH
National Institute for Occupational Safety and Health (NIOSH)
Sodium Hydroxide
NaOHLyeCaustic Soda
pH Adjuster, Preservative
Sodium hydroxide is a strong chemical that helps adjust the pH of products and preserve them from bacteria and mold. It's often used in soap making and cleaning products.
What it is
Sodium hydroxide is a white, odorless, and highly alkaline solid that helps adjust the pH of products and preserve them from bacteria and mold.
Found in
soaps, cleaning products, drain cleaners
The concern
Prolonged exposure to sodium hydroxide can cause severe skin and eye irritation, and respiratory problems.
Legal status
Regulated by OSHA and EPA; must be handled with caution and in well-ventilated areas.
High Concern
Sodium hydroxide can cause severe skin and eye irritation, and prolonged exposure can lead to respiratory problems and other health issues.
Evidence & sources
Article / explainer
Article / explainer
No highly relevant article explainer found yet.
Video explainer
Sodium Hydroxide (Lye) vs. Potassium Hydroxide (Caustic Pot Ash) #soapmaking #makingsoap
Video
Botanical Soap & Bath Co., LLC
Watch videoCommunity questions
Community questions
Community discussions are not used as safety evidence and no highly relevant discussion is shown for this ingredient.
Related ingredient guides
Compare this ingredient with related ingredients and common alternatives.
Triethanolamine
Another formula helper often checked in the same ingredient labels.
Peg 100 Stearate
Another formula helper often checked in the same ingredient labels.
Polysorbate 80
Another formula helper often checked in the same ingredient labels.
Citric Acid
Another formula helper often checked in the same ingredient labels.
Last updated: June 16, 2026