Polyphosphates
The short version
Chain phosphates — used to retain water in processed meat and seafood, increasing yield (and added water).
It's permitted and generally considered safe, but there are a few reasons to be mindful — like sensitivities in some people, debated studies, or intake limits. The Safety section below explains the specifics.
Safety profile
EFSA's 2019 re-evaluation of phosphate additives (E 338–341, E 343, E 450–452) set a group ADI of 40 mg/kg body weight per day, expressed as phosphorus, for phosphates from all sources; it noted that this ADI does not apply to people with moderate to severe reduction in kidney function. JECFA uses a group maximum tolerable daily intake (MTDI) of 70 mg/kg body weight as phosphorus from all sources. The added-water-via-polyphosphate practice has consumer-transparency concerns separate from the phosphate-load concern. Mandatory declaration of added water in some jurisdictions.
Sources
- EFSA — Re-evaluation of phosphoric acid–phosphates – di-, tri- and polyphosphates (E 338–341, E 343, E 450–452) as food additives and the safety of proposed extension of use (EFSA Journal 2019;17(6):5674) — European Food Safety Authority (via PubMed Central), 2019. EFSA group ADI 40 mg/kg bw/day as phosphorus, covering E 452
- JECFA database — Sodium polyphosphates, glassy (sodium hexametaphosphate; Graham's salt), INS 452(i) — WHO / FAO JECFA, 1982. JECFA group MTDI 70 mg/kg bw as P; synonym Graham's salt
- 21 CFR 182.6760 — Sodium hexametaphosphate (GRAS), eCFR as of 1 Oct 2026 — US eCFR (National Archives / GPO), 2026. US: GRAS under GMP
- Regulation (EC) No 1333/2008 on food additives, consolidated text (18 Aug 2026), Annex II Part E — EUR-Lex (European Union), 2026. EU maximum levels for phosphates per category, expressed as P2O5
Checked against these sources on .
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