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E535–E538Fine

Ferrocyanides

Group: Other

Harm level2 of 5Low concern

In plain words

Ferrocyanides (sodium, potassium and calcium) are anti-caking agents that keep salt free-flowing. You meet them mainly in table salt and salt substitutes.

Where you find it: table salt

Our recommendation

No need to avoid them; limiting salt overall matters more.

Possible risks and effects

  • No relevant risk known at normal intake.
  • Kidney changes appeared in animal studies at high doses far above intake from salt.

For experts

Complex hexacyanoferrate(II) salts (E535 sodium, E536 potassium, E538 calcium) in which cyanide is tightly bound to iron and is practically not released; most is excreted unchanged in urine. EFSA re-evaluated them in 2018, set a low ADI and saw no safety concern at permitted uses (salt, salt substitutes; E536 also in wine treatment).

Check another E-number

More from this group

E551Silicon dioxide (silica)E554Sodium aluminium silicateE900DimethylpolysiloxaneE1520Propylene glycolE290Carbon dioxideE422GlycerolE509Calcium chlorideE516Calcium sulphate

This information is educational and based on EFSA assessments and available studies; it does not replace medical advice. With allergies, intolerances or illness, follow your doctor’s advice.