E535 / Acidity regulators & anti-caking agents
Sodium ferrocyanide
Safety in brief
Safe
Recorded EatMatrix rating, not a new clinical review. The amount, your sensitivities and country rules still matter.
- Watch for
- No allergen or sensitivity is recorded for this ingredient here. Check the whole product label; this is not an allergen-free guarantee.
- Our advice
- Read the whole food label and consider how often you eat the product. A name or E number does not tell you the amount, and an ingredient rating cannot assess the entire food.
What it is
Sodium ferrocyanide is an anticaking agent added to table salt and some road-de-icing salt to keep it free-flowing. Despite containing the word 'cyanide,' the compound holds cyanide tightly bound to iron and does not release it under normal food conditions; EFSA and the FDA consider it safe at the low levels permitted in salt. Only trace amounts break down to release cyanide, and only under extreme conditions like strong acid or high heat well beyond normal cooking.
Also appears on labels as: Sodium ferrocyanide, Sodium hexacyanoferrate(II), Na4[Fe(CN)6], E535, E 535, E-535, INS 535, Food additive E535, Anti-caking agent E535, Sodium ferrocyanide food grade, Ferrocyanure de sodium, Ferrocyanuro de sodio.
Dietary information
- Vegan
- Yes
- Halal
- Yes
- Gluten-free
- Yes
- Allergens
- None recorded
Recorded ingredient information. Check the product label or certification: sources, other ingredients and cross-contact can vary.
Research & body effects
Health notes from our ingredient record
- Considered safe at permitted use levels; EFSA has set an acceptable daily intake and found no toxicity concern from normal dietary use.
- Theoretical cyanide release requires conditions (strong acid, high heat) not typically encountered in food preparation or the body.
Other references from our ingredient record
These links come from the original ingredient record. They are separate from the source reviews above and have not all been checked for the exact ingredient, amount consumed or claim. Dates are shown newest first.
- Re‐evaluation of sodium ferrocyanide (E 535), potassium ferrocyanide (E 536) and calcium ferrocyanide (E 538) as food additives — EFSA Panel on Food Additives, EFSA Journal (2018). Official EFSA scientific opinion (bibliographic reference, imported 2026-10-13). It covers the additive as a group assessment and is not an individual human study; read the opinion for its findings.
- Sodium Ferrocyanide: Anti-caking Agent Safety and Regulatory Assessment — EFSA Panel on Food Additives and Flavourings, EFSA Journal - Ferrocyanides Assessment (2018). A detailed safety evaluation of sodium ferrocyanide (E535) examining its use as an anti-caking agent in salt and other crystalline products. The research confirmed that sodium ferrocyanide presents acceptable safety margins when used according to strict regulatory guidelines and approved usage levels. The study noted its effectiveness in preventing clumping in table salt while emphasizing the importance of adherence to maximum permitted levels. The assessment supports its limited use in specific applications with established regulatory controls.[safe_in_moderation]
Country rules
Country checks for E535
Permission depends on the market, type of food, amount and conditions. A scientific opinion or an E-number alone does not establish a legal use. These checks are separate from the stored EatMatrix rating.
Compare all eight markets and their sources
| Market | What is checked |
|---|---|
| European Union | Regulation (EC) 1333/2008, Annex II Part B, version , contains the exact code E535: Sodium ferrocyanide. Listing alone does not allow every food use. Part E food categories, limits, specifications and applicable later acts still need a product-specific check. Source read: . |
| Great Britain | The FSA register record for E535 (Sodium ferrocyanide) lists “Authorised” in England, Scotland and Wales. Register updated: 01 April 2025; record checked: . Food-specific conditions and specifications still need a separate legal check. |
| United States | Complete current-use review pending. Any scoped provision in the label guide above applies only to the stated use. FDA explains the applicable food-additive and GRAS framework. |
| Northern Ireland | Review pending. Check the applicable EU rules and territory arrangements; the GB register alone does not establish this status. FSA guidance is a starting source, not a verified permission for this entry. |
| Canada | Named food-use records located. Health Canada lists the preparations below for specified foods and purposes. This is conditional permission for those uses, not approval of every product or a personal safety verdict. Only the named records and conditions below were located. Exact composition and specifications still need matching. Source tables captured . List publication dates are shown separately. Good Manufacturing Practice (GMP) is a condition of use, not an unlimited amount or a recommended intake. Food and Drug Regulations B.16.003 requires the listed source, purpose, amount and other conditions to match. The official consolidation read was current to 21 September 2026; product specifications and applicable later changes still need checking. Read 2 listed food-use conditionsSodium FerrocyanideHealth Canada: List of Permitted Anticaking Agents. List published ; item S.3.
Sodium FerrocyanideHealth Canada: List of Permitted Food Additives with Other Purposes of Use. List published ; item S.11.
EatMatrix reading: match the exact preparation and food first. A manufacturing limit is not an acceptable daily intake (ADI). A label without the amount cannot establish exposure, and an unlisted name here does not establish a ban. |
| Australia | Review pending. Food Standards Code permissions and conditions need an additive-specific check. FSANZ food-additive rules is a starting source, not a verified permission for this entry. |
| New Zealand | Review pending. Food Standards Code permissions and conditions need an additive-specific check. FSANZ food-additive rules is a starting source, not a verified permission for this entry. |
| Japan | Review pending. The relevant list, identity and use standards need an additive-specific check. CAA food-additive lists is a starting source, not a verified permission for this entry. |
Sources & review status
Check what each source covers: an authority’s conclusion, a research finding and a country’s legal permission answer different questions.
What this guide covers
- Official assessment sources
- Commission-listed EFSA references for E535. Bibliographic identity checked; latest findings and current use rules need separate review.
- Original ingredient record
- 2 research links; newest recorded date: . Sources added separately to this guide are not included in this count.
This guide brings together our ingredient record and the dated sources shown here. Missing information describes a gap in this guide; it does not mean an ingredient is untested, safe or harmful. This is not a complete review of every study, preparation or current country rule. The amount in a product and how it is used still matter.
How to read the ratings, research and country checksAgency labels recorded by EatMatrix
These are imported database classifications, not verified current statements from each authority. Use the dated official sources below for their actual scope and conclusions.
| Authority | Database label |
|---|---|
| FDA | Safe |
| WHO | Safe |
| EFSA | Safe |
| FSANZ | Safe |
| Japan | Safe |
| UK FSA | Safe |
| Health Canada | Safe |
Official assessment sources for E535
The European Commission’s re-evaluation table lists official EFSA documents for this additive. Their identifiers and subjects were checked against publisher bibliographic records. A missing research link in the EatMatrix database does not mean the additive has never been assessed.
Name in the Commission table: Sodium ferrocyanide.
- Re‐evaluation of sodium ferrocyanide (E 535), potassium ferrocyanide (E 536) and calcium ferrocyanide (E 538) as food additives
EFSA scientific opinion. Published: .
These are assessment references, including historical or group assessments. They do not establish the latest scientific conclusion, a human health benefit or risk, or current permission to use the additive in a particular food. Later assessments, corrections and food-use conditions need separate review. The recorded EatMatrix rating above is unchanged.
European Commission re-evaluation table, status as of . EatMatrix checked this bibliography on .
Database updated: . What does an E number mean on a food label?
Common questions
Frequently asked questions
What is EatMatrix's recorded rating for E535?
The recorded EatMatrix rating for E535 (Sodium ferrocyanide) is “Safe”. It is calculated from labels stored in our ingredient database. These labels are not verified current regulator decisions or country permissions. A database update date is not a scientific review date.
Is E535 vegan, halal or gluten-free?
According to our ingredient data for Sodium ferrocyanide — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E535 and why is it used?
Sodium ferrocyanide is an anticaking agent added to table salt and some road-de-icing salt to keep it free-flowing. Despite containing the word 'cyanide,' the compound holds cyanide tightly bound to iron and does not release it under normal food conditions; EFSA and the FDA consider it safe at the low levels permitted in salt. Only trace amounts break down to release cyanide, and only under extreme conditions like strong acid or high heat well beyond normal cooking.
Does E535 contain allergens?
No known allergens are recorded for Sodium ferrocyanide.
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This page shows information and classifications recorded in our ingredient database. Current scientific and market-specific verification remains pending as described above. It is general information, not medical advice.