Potassium chloride
7447-40-7 · Acronitol · Celeka · Chloride of potash · Chloropotassuril · Chlorvescent · Durekal · Durules · E 508 · Enpott · Enseal · K-Contin · K-Lease · K-Lor · K-Tab · Kadalex · Kalcorid · Kaleorid · Kaliduron · Kaliglutol · Kalilente · Kalinorm · Kaliolite · Kalipor · Kalipoz · Kalitabs · Kalitrans Retard · Kalium Duriles · Kalium Durules · Kalium Retard · Kaochlor · Kaon Cl · Kaon-Cl · Kato · Kay Ciel · Keylyte · Klor-Con · Kloren · Klorvess · Klotrix · Micro-K · Miopotasio · Monopotassium chloride · Muriate of potash · Natural sylvite · Neobakasal · Peter-kal · Pfiklor · Potasion · Potasol · Potassium chloride · Potassium monochloride · Potassium muriate · Potavescent · Rekawan · Rekawan Retard · Repone K · Slow-K · Steropotassium · Sylvine · Sylvite · Ten-K · E508 · 508 · potassium chloride · Potassium chloride · Chlorek potasu · Chlorid draselný · Chlorure de potassium · Cloreto de potássio · CLORURO DE POTASIO · Cloruro di potassio · Cloruro potásico · Clorură de potasiu · Kaaliumkloriid · Kalijev klorid · Kalio chloridas · Kaliumchlorid · Kaliumchloride · Kaliumklorid · Kaliumkloridi · Klorur tal-potassju · Kálium-klorid · Kālija hlorīds · Potassium chloride · Χλωριούχο κάλιο · Калиев хлоридE number E508INS 508CAS 7447-40-7
Listed as a thickener and a stabiliser by Canada, Codex and the US.
Listed as thickeners (CA, US, Codex) · stabilisers (CA, US, Codex) · acidity regulators (CA, US) · flavour enhancers (US, Codex) · emulsifiers (CA) · firming agents (Codex) · nutrient supplements (US) · enzymes (US) · flavouring agents and adjuvants (US) · yeast foods (CA) · processing aids (US)
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- United States: Stabilizer or thickener — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Stabilizers and thickeners — 21 CFR 184.1622, citing 21 CFR 170.3(o)(28)
- Codex Alimentarius: Thickener — CXS 192-1995 Table One, INS 508
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- United States: Stabilizer or thickener — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Stabilizers and thickeners — 21 CFR 184.1622, citing 21 CFR 170.3(o)(28)
- Codex Alimentarius: Stabilizer — CXS 192-1995 Table One, INS 508
- Canada: Acidity regulator — Health Canada, List of Permitted Acidity Regulators and Acid-Reacting Materials (List 10)
- United States: pH control agent — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: pH control agents — 21 CFR 184.1622, citing 21 CFR 170.3(o)(23)
- United States: Flavor enhancer — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Flavor enhancers — 21 CFR 184.1622, citing 21 CFR 170.3(o)(11)
- Codex Alimentarius: Flavour enhancer — CXS 192-1995 Table One, INS 508
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- Codex Alimentarius: Firming agent — CXS 192-1995 Table One, INS 508
- United States: Nutrient supplement — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Nutrient supplements — 21 CFR 184.1622, citing 21 CFR 170.3(o)(20)
- United States: Enzyme — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Flavoring agent or adjuvant — FDA, Substances Added to Food: POTASSIUM CHLORIDE
- United States: Flavoring agents and adjuvants — 21 CFR 184.1622, citing 21 CFR 170.3(o)(12)
- Canada: Yeast food — Health Canada, List of Permitted Yeast Foods (List 14)
- United States: Processing aid — FDA, Substances Added to Food: POTASSIUM CHLORIDE

Potassium chloride is the main substitute for ordinary salt in reduced-sodium foods. It tastes salty but carries a metallic bitterness, which is why it is usually blended with sodium chloride rather than replacing it outright.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| Australia and New Zealand | Permitted, with conditions | 55 food categories no numerical limit (good manufacturing practice) Show every food category
| Food Standards Code, Schedule 15, S15—5and 54 further provisionsretrieved 2026-10-17 |
| Canada | Permitted | no numerical limit (good manufacturing practice) 4 permitted uses Show every permitted use
| Health Canadaand 3 further provisionsretrieved 2026-10-17 |
| European Union | Permitted, with conditions | 68 food categories Show every food category
| Regulation (EC) No 1333/2008, Annex IIand 67 further provisionsretrieved 2026-10-18 |
| Great Britain | Permitted, with conditions | 66 food categories Show every food category
| Assimilated Regulation (EC) No 1333/2008, Annex II (as at 28 June 2024)and 65 further provisionsretrieved 2026-10-18 |
| Japan | Permitted, with conditions | Designated additive: Appended Table 1, item 86, 塩化カリウム (“Potassium Chloride” in the unofficial English translation). …Designated additive: Appended Table 1, item 86, 塩化カリウム (“Potassium Chloride” in the unofficial English translation). Standards for use — Specifications and Standards for Foods, Food Additives, etc. (MHW Notification No. 370 of 1959), Part II (Food Additives), F (Standards for use): The Notification sets no standard for use (使用基準) for this additive, so it is not restricted there to particular foods or amounts. Compositional specifications for this additive, in the same Notification, are not imported and are not shown here; nor are the general rules in F 添加物一般, which apply to every additive. | Regulations for Enforcement of the Food Sanitation Act (MHW Ordinance No. 23 of 1948), Appended Table 1retrieved 2026-10-18 |
| South Korea | Permitted, with conditions | Designated food additive: Standards and Specifications for Food Additives, Part III, 1. …Designated food additive: Standards and Specifications for Food Additives, Part III, 1. 일반식품첨가물 (general food additives), 염화칼륨 (“Potassium Chloride”, the English the Code prints beside it); the Code marks it as also usable as a nutrient fortifier; 3. 영양강화제 (nutrient fortifiers), 염화칼륨; nutrient: 칼륨(K); the Code marks it as also usable as a general food additive. Main use (주용도) of 염화칼륨: 향미증진제, 젤형성제. Standard for use (사용기준) of 염화칼륨: (1) [to be used under the general standard for use in II. 2. 1), the minimum amount that achieves the technical effect, with no limit set for this additive in particular] “II. 2. 1)의 규정에 따라 사용하여야 한다.” The Korean is the standard as published. There is no official English translation of the current Code (the English version on MFDS’s website is the 2020 edition and has no legal effect); the English in square brackets is this site’s description of what each sentence does, not a translation of the foods or the levels. Compositional specifications (Part IV) are not imported, nor are the general standards in Part II, which apply to every additive. | Standards and Specifications for Food Additives (식품첨가물의 기준 및 규격), MFDS Notification, Part III (Standards for use, by item)retrieved 2026-10-18 |
| United States | Permitted | 21 CFR 184.1622retrieved 2026-10-17 | |
| Codex Alimentarius | Permitted, with conditions | 14 food categories no numerical limit (good manufacturing practice) Show every food category and its notes
| CXS 192-1995 Table Three, INS 508and 14 further provisionsretrieved 2026-09-07 |
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.
| Australia and New Zealand | — | 55 GMP |
|---|---|---|
| Canada | — | 4 GMP |
| European Union | — | 46 several limits, 22 no quantity stated |
| Great Britain | — | 66 quantum satis |
| Japan | — | 1 no quantity stated |
| South Korea | — | 1 no quantity stated |
| United States | — | 1 no quantity stated |
| Codex Alimentarius | — | 15 GMP |
No regulator sets a figure for Potassium chloride. 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
Mined as sylvite or recovered from brines, then purified.
- Vegan
- Vegetarian
Compare other additives on the dietary indexes.
- CAS registry number
- 7447-40-7
- InChIKey
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M
- PubChem
- CID 4873
The two specifications, compared
The European Union sets identity and purity by regulation; JECFA publishes its own through FAO, advisory until a country adopts it. Both documents are below in full. These are the parameters each puts a number on.
| Parameter | European Union | JECFA |
|---|---|---|
| Assay | no less than 99 % | no less than 99 % |
| Loss on drying | no more than 1 % | no more than 1 % |
| Lead | no more than 2 mg/kg | no more than 2 mg/kg |
| Arsenic | no more than 3 mg/kg | — |
| Mercury | no more than 1 mg/kg | — |
| Cadmium | no more than 1 mg/kg | — |
The two documents state the same figures for every parameter compared here.
How the EU defines it
The legal specification an additive must meet to be sold as this E number in the EU — what it is, how it may be made, and the purity it must reach. From Commission Regulation (EU) No 231/2012.
E 508 Potassium chloride
Synonyms: Sylvine; Sylvite
Assay, identification and purity criteria
Description and assay
- Einecs
- 231-211-8
- Chemical name
- Potassium chloride
- Chemical formula
- KCl
- Molecular weight
- 74,56
- Assay
- Content not less than 99 % on the dried basis
- Description
- Colourless, elongated, prismatic or cubital crystals or white granular powder. Odourless
Identification
- Solubility
- Freely soluble in water. Insoluble in ethanol
- Test for potassium
- Passes test
- Test for chloride
- Passes test
Purity criteria
- Loss on drying
- Not more than 1 % (105 °C, 2 hours)
- Test for sodium
- Negative
- Arsenic
- Not more than 3 mg/kg
- Lead
- Not more than 2 mg/kg
- Mercury
- Not more than 1 mg/kg
- Cadmium
- Not more than 1 mg/kg
How JECFA defines it
The international specification for identity and purity, prepared by the Joint FAO/WHO Expert Committee on Food Additives and published by FAO. It is a different document from any above, written by a different body and revised on its own cycle; it is advisory, and a country adopts it or does not.
INS 508 Potassium Chloride
Synonyms: Sylvine, sylvite; INS No. 508 Sylvine; Sylvite
Assay, identification and purity criteria
Description and assay
- Specification history
- Prepared at the 23rd JECFA (1979), published in FNP 12 (1979) and in FNP 52 (1992). Metals and arsenic specifications revised at the 63rd JECFA (2004). A group ADI 'not limited' for hydrochloric acid and its ammonium, Mg, K salts was established at the 23rd JECFA (1979)
- Chemical names
- Potassium chloride
- C.A.S. number
- 7447-40-7
- Chemical formula
- KCl
- Formula weight
- 74.56
- Assay
- Not less than 99.0% on the dried basis
- DESCRIPTION
- Colourless, elongated, prismatic, or cubital crystals, or white granular powder; odourless
- FUNCTIONAL USES
- Seasoning agent, gelling agent, yeast food
- METHOD OF ASSAY
- Dissolve about 250 mg of the dried sample, accurately weighed in 50 ml of water in a glass-stoppered flask. Add, while agitating, 50 ml of 0.1 N silver nitrate, 3 ml of nitric acid, and 5 ml of nitrobenzene, shake vigorously, add 2 ml of ferric ammonium sulfate TS, and titrate the excess silver nitrate with 0.1 N ammonium thiocyanate. Each ml of 0.1 N silver nitrate is equivalent to 7.456 mg of KCl.
Identification
- Solubility (Vol. 4)
- Freely soluble in water; insoluble in ethanol
- Test for potassium (Vol. 4)
- Passes test
- Test for chloride (Vol. 4)
- Passes test
Purity criteria
- Loss on drying (Vol. 4)
- Not more than 1% (105 o , 2 h)
- Acidity or alkalinity
- To a solution of 5 g of the sample in 50 ml of recently boiled and cooled water add 3 drops of phenolphthalein TS. No pink colour is produced. Then add 0.3 ml of 0.02 N sodium hydroxide. A pink colour is produced.
- Iodide or bromide
- Dissolve 2 g of the sample in 6 ml of water, add 1 ml of chloroform, and then add, dropwise and with constant agitation, 5 ml of a mixture of equal parts of chlorine TS and water. The chloroform is free from even a transient violet or permanent orange colour.
- Test for sodium (Vol. 4)
- Negative test
- Lead (Vol. 4)
- Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in Volume 4, “Instrumental Methods.”
Authorised in other additives, enzymes, flavourings and nutrients
These authorisations are not for use in food. They let this substance be used inside another additive, a food enzyme, a flavouring or a nutrient preparation — often as a carrier — and it reaches food only as part of that product. Annex III to Regulation (EC) No 1333/2008.
| Part | May be used in | Maximum level | Citation |
|---|---|---|---|
| Annex III, Part 1: Carriers in food additives | All food additives | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 1 |
| Annex III, Part 2: Food additives other than carriers in food additives | All food additive preparationsAuthorised as a member of Table 1 of Part 6, listed as "Table 1" Note (1): Except enzymes authorised as food additives. | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 2, via Table 1 of Part 6 |
| Annex III, Part 3: Food additives including carriers in food enzymes | Food enzymesCan be used as a carrier: Yes Note (1): Including enzymes authorised as food additives. | In enzyme preparation: quantum satis In final food except beverages: quantum satis In beverages: quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 3 |
| Annex III, Part 4: Food additives including carriers in food flavourings | All flavouringsAuthorised as a member of Table 1 of Part 6, listed as "Table 1" | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 4, via Table 1 of Part 6 |
| Annex III, Part 5, Section A: Food additives added in nutrients except in nutrients intended to be used in foodstuffs listed in Part E, point 01.10, of Annex II and foodstuffs for infants and young children listed in Part E, point 13.1, of Annex II | All nutrients | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 5, Section A |
Every name it appears under
87 recorded names. A label may use any of them.
E number
- E508
INS number
- 508
CAS registry number
- 7447-40-7
As it appears in regulation
- Potassium chloride
Other names
- Acronitol
- Celeka
- Chloride of potash
- Chloropotassuril
- Chlorvescent
- Durekal
- Durules
- E 508
- Enpott
- Enseal
- K-Contin
- K-Lease
- K-Lor
- K-Tab
- Kadalex
- Kalcorid
- Kaleorid
- Kaliduron
- Kaliglutol
- Kalilente
- Kalinorm
- Kaliolite
- Kalipor
- Kalipoz
- Kalitabs
- Kalitrans Retard
- Kalium Duriles
- Kalium Durules
- Kalium Retard
- Kaochlor
- Kaon Cl
- Kaon-Cl
- Kato
- Kay Ciel
- Keylyte
- Klor-Con
- Kloren
- Klorvess
- Klotrix
- Micro-K
- Miopotasio
- Monopotassium chloride
- Muriate of potash
- Natural sylvite
- Neobakasal
- Peter-kal
- Pfiklor
- Potasion
- Potasol
- Potassium chloride
- Potassium monochloride
- Potassium muriate
- Potavescent
- Rekawan
- Rekawan Retard
- Repone K
- Slow-K
- Steropotassium
- Sylvine
- Sylvite
- Ten-K
Systematic names
- potassium chloride
Hazard reference values
| Type | Value | Population | Assessed by | Opinion |
|---|---|---|---|---|
| ADI | not limited | — | JECFA | 1979 |
Evidence and how bodies read it
What assessing bodies concluded
Each conclusion is paraphrased in the body's own framing, from the published opinion linked beneath it. Where bodies differ, both stand; this site does not adjudicate between them or add a view of its own.
EFSA 2019
The FAF Panel found no concern for genotoxicity or carcinogenicity for hydrochloric acid and its potassium, calcium and magnesium salts (E 507–E 509, E 511), and used a human reference value of 40 mg chloride/kg bw/day. Although high-percentile exposure in toddlers, children and adolescents was slightly above that value, it concluded that exposure to chloride from these additives does not raise a safety concern at reported uses.
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 E 508?
- E 508 is Potassium chloride. Potassium chloride is the main substitute for ordinary salt in reduced-sodium foods. It tastes salty but carries a metallic bitterness, which is why it is usually blended with sodium chloride rather than replacing it outright.
- What is Potassium chloride used for in food?
- It is listed as a thickener and a stabiliser — the role Canada, Codex and the US assign it. This page shows every function each regulator records, with the citation for each.
- Where is Potassium chloride permitted?
- Of the seven regulators this site reads, Australia and New Zealand, Canada, the EU, Great Britain, Japan, South Korea, the US and the Codex standard permit it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
- Is Potassium chloride vegan?
- Yes. Potassium chloride is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.
Sources for this page
- anz retrieved 2026-10-17
- ca retrieved 2026-10-17
- eu retrieved 2026-10-18
- gb retrieved 2026-10-18
- jp retrieved 2026-10-18
- kr retrieved 2026-10-18
- ecfr retrieved 2026-10-17
- gsfa retrieved 2026-09-07
- euspecs retrieved 2026-10-18
- jecfaspecs retrieved 2026-09-23
Full licence terms and publisher details on Sources. How this page is built and updated: Method.
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