Phosphorus oxychloride

CAS 10025-87-3

Listed as an acidity regulator and a starch-modifying agent by the US and Canada.

Listed as acidity regulators (US) · starch-modifying agents (CA)
Chemical structure of Phosphorus oxychloride, from PubChem compound 24813
Structure from PubChem CID 24813 (National Library of Medicine, public domain). A depiction of one compound: where a listing covers a family, or a substance has no single structure, this page shows none.

A cross-linking reagent for starch: it joins starch chains together, so that the starch holds up to heat, acid and shear. The modified starch is what reaches the food.

Where it is and isn’t permitted

Status of Phosphorus oxychloride by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
Australia and New ZealandFood Standards Australia New ZealandNo 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.
CanadaHealth CanadaPermitted

no numerical limit (good manufacturing practice)

In: Starch used in the manufacture of modified starch. Purpose: Starch-modifying agent. Limit: Good Manufacturing Practice.

Health Canada, List of Permitted Starch-Modifying Agents (List 13), item P.2retrieved 2026-10-17
European UnionEuropean Commission / EFSANo 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 BritainFood Standards Agency / Food Standards ScotlandNo 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.
JapanConsumer Affairs AgencyNo 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 KoreaMinistry of Food and Drug SafetyNo 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 StatesFood and Drug AdministrationNot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.
Codex AlimentariusCodex Alimentarius Commission / JECFANot 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.

Canada—1 GMP

No regulator sets a figure for Phosphorus oxychloride. 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

Made by reacting phosphorus trichloride with oxygen or with phosphorus pentoxide.

  • Vegan
  • Vegetarian

Compare other additives on the dietary indexes.

CAS registry number
10025-87-3
InChIKey
XHXFXVLFKHQFAL-UHFFFAOYSA-N
PubChem
CID 24813

Every name it appears under

60 recorded names. A label may use any of them.

CAS registry number

  • 10025-87-3

Other names

  • [PCl3O]
  • Fosforoxychlorid
  • HSDB 784
  • OPCl3
  • Oxychlorid fosforecny
  • phosphor oxychloride
  • phosphor us oxychloride
  • phosphoric oxychloride
  • Phosphoric trichloride
  • phosphoricchloride
  • phosphorous oxichloride
  • phosphorous oxy chloride
  • phosphorous oxy-chloride
  • Phosphorous oxychloride
  • phosphorous oxychoride
  • Phosphorous oxycloride
  • phosphorous-oxy-chloride
  • phosphorous-oxychloride
  • phosphorousoxy chloride
  • phosphorousoxychloride
  • Phosphoroxidchlorid
  • phosphoroxy-chloride
  • Phosphoroxychlorid
  • Phosphoroxychloride
  • phosphoroyl trichloride
  • Phosphortrichloridoxid
  • Phosphorus chloride oxide (POCl3)
  • phosphorus oxichloride
  • Phosphorus oxide trichloride
  • phosphorus oxy-chloride
  • phosphorus oxychioride
  • phosphorus oxychlorid
  • Phosphorus Oxychloride
  • phosphorus oxychloride-
  • Phosphorus oxychoride
  • Phosphorus oxycloride
  • Phosphorus oxytrichloride
  • phosphorus trichloride oxide
  • Phosphorus(V) oxide chloride
  • Phosphorus(V) oxychloride
  • Phosphorus(V) oxychloride, 99.999%
  • Phosphorus(V) oxychloride, ReagentPlus(R), 99%
  • Phosphorus(V) trichloride oxide
  • phosphorus-oxychloride
  • Phosphorusoxy chloride
  • phosphorusoxychloride
  • Phosphoryl chloride
  • phosphoryl choride
  • Phosphoryl trichloride
  • Phosphoryl trichoride
  • Phosphorylchlorid
  • phosphorylchloride
  • phosphoryltrichloride
  • POCl3
  • trichloridooxidophosphorus
  • Trichlorooxophosphorus(V)
  • Trichlorophosphine oxide
  • Trichlorophosphorus oxide
  • trichlorure de phosphoryle

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 Phosphorus oxychloride?
A cross-linking reagent for starch: it joins starch chains together, so that the starch holds up to heat, acid and shear. The modified starch is what reaches the food.
What is Phosphorus oxychloride used for in food?
It is listed as an acidity regulator and a starch-modifying agent — the role the US and Canada assign it. This page shows every function each regulator records, with the citation for each.
Where is Phosphorus oxychloride permitted?
Of the seven regulators this site reads, Canada 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 Phosphorus oxychloride vegan?
Yes. Phosphorus oxychloride is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.

Sources for this page

  • ca retrieved 2026-10-17

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable: a JSON record of this additive is given on request —how to ask for access.

Follow changes to Phosphorus oxychloride:Atom feed — regulatory events, and any change the weekly refresh detects in its provisions.