Tetrasodium Pyrophosphate

AKA: 7722-88-5, Tetrasodium diphosphate, Phosphotex, Diphosphoric acid, Tetrasodium salt, Sodium diphosphate, Victor TSPP, Natrium pyrophosphat
Synthetic
Chelating Agent
Clean
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
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
Traditional Use
Inorganic salt developed in the 20th century as a buffering and chelating agent in cosmetics. Used industrially before being adopted to improve product stability and texture.
EWG
1
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Status
USApermitted
EUrestricted
JAPANrestricted
CANADArestricted
Skin Types
all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
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.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR