murphyTetrasodium Pyrophosphate
AKA: 7722-88-5, Tetrasodium diphosphate, Phosphotex, Diphosphoric acid, Tetrasodium salt, Sodium diphosphate, Victor TSPP, Natrium pyrophosphat
Synthetic
Chelating Agent
Clean
OriginDerived from phosphoric acid and sodium compounds, a member of the inorganic phosphate chemical family. Synthesized through neutralization and condensation reactions of sodium phosphate precursors under controlled heating.
Tetrasodium pyrophosphate appears as odorless, white powder or granules. mp: 995 °C. Density: 2.53 g/cm3. Solubility in water: 3.16 g/100 mL (cold water); 40.26 g/100 mL boiling water. Used as a wool de-fatting agent, in bleaching operations, as a food additive. The related substance tetrasodium pyrophosphate decahydrate (Na4P2O7*10H2O) occurs as colorless transparent crystals. Loses its water when heated to 93.8 °C.
Solubility 7 % at 77 °F (NIOSH, 2024)
Formula
Na4O7P2
Mol. Weight
265.90
CAS #
7722-88-5
Form
Powder
State
Tetrasodium pyrophosphate appears as odorless, white powder or granules. mp: 995 °C. Density: 2.53 g/cm3. Solubility in water: 3.16 g/100 mL (cold water); 40.26 g/100 mL boiling water. Used as a wool
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
Functions
Anticaking
Buffering
Chelating
Grabs onto metal ions in water that would destabilize the formula. Keeps your product from going bad or changing color.
Oral Care
Prevents Clumping
Stabilizes pH
Removes Metal Ions
Supports dental health
Maintains optimal pH
Binds metal ions
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
1
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Mixed Skin Irritation Results
5 studies / 2 irritating / 3 not irritating (CIR 710)
Eye Irritant in Testing
2 studies / 2 irritating / reactions minimal (CIR 710)
Concentration Guide
Leave-on0.03–3%
Rinse-off0.0000014–6%
0%50%100%
CIR reported use · 2015 survey
Regulatory Agencies
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR