So
Sodium Trimetaphosphate
Sodium Trimetaphosphate
A sodium phosphate used to buffer pH and bind metals.
What it does
It’s a ring-shaped sodium phosphate. The EU lists it to hold pH steady, bind metals and keep powders from caking.
The evidence, graded
expert consensusUS safety reviewers (2021) assessed 31 ingredients, phosphoric acid and its salts, which products use to buffer, adjust pH or bind metals. They judged all 31 safe as used, in products made not to irritate; sodium trimetaphosphate is on their list, though no uses of it were reported to them. Some of the salts irritated skin at strengths from 1% to 50%. They asked makers to limit heavy metals.Johnson 2021 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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