Phosphoric Acid
AKA “ORTHOPHOSPHORIC ACID, o-Phosphoric acid, Wc-reiniger, Acidum phosphoricum, Sonac, Phosphorsaeure, Evits, Acide phosphorique”
Synthetic
Ingredient Facts
Phosphoric acid
AKA: ORTHOPHOSPHORIC ACID, O-Phosphoric acid, Wc-reiniger, Acidum phosphoricum, Sonac, Phosphorsaeure, Evits, Acide phosphorique
Synthetic · Buffering · EWG: 4
Synthetic
Synthetic
Clean
A pH balancer that helps stabilize the formula and maintain product effectiveness on skin and hair.
Solubility Miscible (NIOSH, 2024)
Formula
H3O4P
Mol. Weight
98.00
CAS #
7664-38-2
Form
Liquid
State
Phosphoric acid appears as a clear colorless liquid or transparent crystalline solid. The pure solid melts at 42.35 °C and has a density of 1.834 g / cm3. Liquid is usually an 85% aqueous solution. Sh
See origin →
Functions
Buffering
pH Adjusting
Stabilizes pH
Antioxidant Protection
Locks In Moisture
Fights Bacteria
Traditional Use
A mineral acid known since ancient times from phosphate deposits; used historically as a food preservative and cleaning agent. In cosmetics, developed as a pH adjuster and chemical exfoliant in modern skincare formulations.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
Safety Assessment of Phosphoric Acid and Its Salts as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Metaphosphoric Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Phosphoric Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Phosphoric Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Verified Feb 2026
Data: PubChem · CosIng · EWG · CIR