Ferric sulfate
10028-22-5 · 142906-29-4 · 3HWS7HF5XD · 4YKQ1X5E5Y · CCRIS 7885 · Coquimbite mineral · diferric;trisulfate · Diiron tris(sulphate) · Diiron trisulfate · Ferric persulfate · Ferric sesquisulfate · FERRIC SULFATE · Ferric sulfate (USP) · FERRIC SULFATE ANHYDROUS · FERRIC SULFATE--N/H · Ferric sulphate hydrate · Ferric tersulfate · Ferric trisulfate pentahydrate · HSDB 6311 · Iron persulfate · Iron sesquisulfate · Iron sulfate (2:3) · Iron sulfate (Fe2(SO4)3) · Iron sulfate (fe2(so4)3) hydrate · Iron tersulfate · Iron(3+) sulfate · Iron(3+) sulfate (2/3) · Iron(3+) sulfate, (2:3) · iron(3+);trisulfate · Iron(III) sulfate · Iron(III) sulfate (Fe2(SO4)3) · Iron(III) sulfate pentahydrate · iron(III) sulfate(VI) · iron(III)sulphate · Pix 115 · STASIS · Sulfuric acid, iron(3+) salt (3:2) · Viscostat · Ferric sulfateCAS 10028-22-5
Listed as a flavouring agent by the US.
Listed as flavouring agents and adjuvants (US)
- United States: Flavoring agent or adjuvant — FDA, Substances Added to Food: FERRIC SULFATE
- United States: Flavoring agents and adjuvants — 21 CFR 184.1307, citing 21 CFR 170.3(o)(12)
Ferric sulfate is an iron source and processing aid used in some fortified foods and in water treatment.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| Australia and New Zealand | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Canada | No listing matchedHealth Canada’s lists name additives without E or INS numbers, so this site matches them by exact name. A substance listed there under a name this site does not recognise has no row here. | ||
| European Union | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Great Britain | No listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it. | ||
| Japan | No listing matchedThis site imports only Japan’s list of designated additives (Appended Table 1 to the Regulations for Enforcement of the Food Sanitation Act), matched by English name. Existing additives, natural flavouring agents and ordinary foods used as additives are permitted outside that list and are not imported, so an empty row does not show that Japan does not permit the substance. | ||
| South Korea | No listing matchedThis site imports Part III of South Korea’s Standards and Specifications for Food Additives, matched by CAS number, then INS number, then exact name. Mixed preparations and sanitisers are not imported, and an entry whose identifiers disagreed with a page’s is held for review, so an empty row does not show that South Korea does not permit the substance. | ||
| United States | Permitted | 21 CFR 184.1307retrieved 2026-10-17 | |
| Codex Alimentarius | Not listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited. |
How much is permitted
A listing usually limits the quantity as well as the food. Only one of the forms that takes is a figure: quantum satis and good manufacturing practice permit the amount the technological effect requires and no more, which is a limit rather than the absence of one. Figures below are the range across every food category this page is listed in, and categories differ between regulators — see how much is permitted.
| United States | — | 1 no quantity stated |
|---|
No regulator sets a figure for Ferric sulfate. That is not an absence of control: where the listing says quantum satis or good manufacturing practice, the quantity is limited to what the effect requires.
What it is made from
Produced by oxidising ferrous sulfate or dissolving iron oxide in sulfuric acid.
- Vegan
- Vegetarian
Compare other additives on the dietary indexes.
- CAS registry number
- 10028-22-5
- InChIKey
- RUTXIHLAWFEWGM-UHFFFAOYSA-H
- PubChem
- CID 24826
Every name it appears under
39 recorded names. A label may use any of them.
CAS registry number
- 10028-22-5
- 142906-29-4
As it appears in regulation
- Ferric sulfate
Other names
- 3HWS7HF5XD
- 4YKQ1X5E5Y
- CCRIS 7885
- Coquimbite mineral
- diferric;trisulfate
- Diiron tris(sulphate)
- Diiron trisulfate
- Ferric persulfate
- Ferric sesquisulfate
- FERRIC SULFATE
- Ferric sulfate (USP)
- FERRIC SULFATE ANHYDROUS
- FERRIC SULFATE--N/H
- Ferric sulphate hydrate
- Ferric tersulfate
- Ferric trisulfate pentahydrate
- HSDB 6311
- Iron persulfate
- Iron sesquisulfate
- Iron sulfate (2:3)
- Iron sulfate (Fe2(SO4)3)
- Iron sulfate (fe2(so4)3) hydrate
- Iron tersulfate
- Iron(3+) sulfate
- Iron(3+) sulfate (2/3)
- Iron(3+) sulfate, (2:3)
- iron(3+);trisulfate
- Iron(III) sulfate
- Iron(III) sulfate (Fe2(SO4)3)
- Iron(III) sulfate pentahydrate
- iron(III) sulfate(VI)
- iron(III)sulphate
- Pix 115
- STASIS
- Sulfuric acid, iron(3+) salt (3:2)
- Viscostat
Hazard reference values
No reference value for this substance in the sources we hold.
Evidence and how bodies read it
Studies, and the differing conclusions regulators drew from them, are curated rather than machine-read, and none has been written for this substance yet.
Common questions
Assembled from what is above, in the words the questions are usually asked in. Each answer is the same statement the relevant section makes, with the same citations behind it.
- What is Ferric sulfate?
- Ferric sulfate is an iron source and processing aid used in some fortified foods and in water treatment.
- What is Ferric sulfate used for in food?
- It is listed as a flavouring agent — the role the US assigns it. This page shows every function each regulator records, with the citation for each.
- Is Ferric sulfate banned in Europe?
- No. Ferric sulfate is not on the EU's list of authorised food additives, but it would not be expected to be: every role regulators give it — flavouring agent — the EU regulates under separate law. Its absence from the additives list says nothing about whether it is permitted in Europe.
- Where is Ferric sulfate permitted?
- Of the seven regulators this site reads, the US permits it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
- Is Ferric sulfate vegan?
- Yes. Ferric sulfate is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.
Sources for this page
- ecfr retrieved 2026-10-17
Full licence terms and publisher details on Sources. How this page is built and updated: Method.
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