Potassium bromate: is it banned, and what is it doing in bread?
Where potassium bromate is allowed
United States
Permitted with conditionsStill permitted under FDA rules, with limits. Standardized bread, rolls and buns may contain bromated flour or potassium bromate, and the combined total of potassium bromate and certain related dough agents may not exceed 0.0075 parts per 100 parts of flour by weight (21 CFR 136.110(c)(14)). A separate rule (21 CFR 172.730) covers malting barley for beer and spirits. FDA lists potassium bromate on its chemicals-under-review page (current as of July 29, 2026) at the 'Review of Information' step, which is the first step of its review process. [1, 2, 3, 11, 12]
Canada
Not permittedPotassium bromate used to be a permitted food additive in Canada but was delisted in 1994, so it is no longer permitted as a food additive in foods offered for sale there, according to the federal government's 2010 screening assessment of the substance. Health Canada's current List of Permitted Flour Treatment Agents (modified December 18, 2024) does not include it. [5, 13]
European Union
Not permittedEU law says only additives on the Union list (Annex II of Regulation (EC) No 1333/2008) may be used in food, and potassium bromate is not on that list. We searched the full consolidated text dated August 18, 2026 and the word 'bromate' does not appear in it. [6]
What is potassium bromate?
Potassium bromate is a chemical compound, the potassium salt of bromic acid. FDA's Substances Added to Food database lists its technical effects as dough strengthener, flour treating agent, leavening agent and oxidizing or reducing agent. In plain terms, it is added to flour or dough to help the dough stay strong and rise well in the oven.
In US rules, flour treated with it is called 'bromated flour', and FDA's standard for that flour allows potassium bromate at no more than 50 parts per million of the finished flour (21 CFR 137.155). A second, narrower US authorization covers malting barley, where the treated malt may only go into beer or distilled spirits.
Why it's used, and where you'll find it
Under the US bread standard, potassium bromate is listed together with calcium bromate, potassium iodate, calcium iodate and calcium peroxide as options for strengthening dough, and the whole group shares a single cap on how much can be used.
What the research and regulators say
What IARC concluded
In 1999, IARC classified potassium bromate as 'possibly carcinogenic to humans' (Group 2B). That rating rests on 'sufficient evidence' in experimental animals and 'inadequate evidence' in humans. In the animal studies, potassium bromate produced kidney tumors and thyroid tumors in rats of each sex and peritoneal mesotheliomas in male rats, and a low incidence of kidney tumors in male mice. The rating reflects those animal experiments, not a measurement of what people actually take in from bread. [7]
The 'it bakes away' argument, and where it is disputed
FDA's position is that when manufacturers use potassium bromate properly it converts to potassium bromide, which FDA describes as harmless and similar to salt, and that normal control measures keep any leftover bromate in finished products at safe levels. FDA says it worked with the American Bakers Association to improve baking technology and testing so residual bromate is minimized. The international expert committee JECFA (run by FAO and WHO) took a more cautious view: in 1995, in light of new data showing residual levels of bromate in bread, it said its 1992 conclusions still applied, and its database lists use as a flour-treatment agent as 'not acceptable'. [4, 8]
Where things stand in US law
FDA has not revoked the authorization. States are moving separately. California's law (AB 418, Chapter 328 of the Statutes of 2023, signed October 7, 2023) prohibits manufacturing, selling, delivering, distributing, holding or offering for sale in commerce a food product for human consumption that contains potassium bromate, along with brominated vegetable oil, propylparaben and red dye 3, commencing January 1, 2027. Civil penalties are up to $5,000 for a first violation and $10,000 for each later one. In New York, a bill that would ban potassium bromate along with red dye 3 and propylparaben (S1239) passed both houses on April 21, 2026, but when we checked on September 19, 2026 the State Senate's bill page showed no governor's signature and the Senate's own release said it awaited the governor's action, so we cannot confirm it has become law. [3, 9, 10, 14]
Who might choose to avoid it
Some people choose to avoid potassium bromate because of IARC's Group 2B rating and because Canada and the EU do not allow it, even though FDA says properly baked products contain only safe residues. If you want to skip it, the practical step is reading the ingredient list. This page is not medical advice.
How to spot it on a label
In the US, look for 'potassium bromate' or 'bromated flour' in the ingredient list of bread, rolls, buns and other baked goods; the standard for bread requires each ingredient used to be declared on the label. It is not an authorised additive in Canada or the EU, so it should not appear on labels of food made for those markets.
Check what's in your own productsScan a barcode or a label photo and Label X-Ray flags potassium bromate and everything else in plain English, with your allergies checked automatically.
Frequently asked questions
Is potassium bromate banned in Canada?
In effect, yes. The Government of Canada's screening assessment says it was delisted as a food additive in 1994 and is no longer permitted in foods offered for sale in Canada.
Is potassium bromate banned in Europe?
It is not authorised. EU law only allows additives on the Union list, and potassium bromate is not on it in the consolidated Regulation (EC) No 1333/2008 dated August 18, 2026.
Is potassium bromate banned in the US?
Not at the federal level. FDA rules still allow it in bread, rolls and buns up to a set limit. California will ban it from January 1, 2027.
Is potassium bromate banned in California?
It will be. AB 418 prohibits potassium bromate in food for human consumption commencing January 1, 2027, with civil penalties of up to $5,000 for a first violation and $10,000 for each later one.
Is potassium bromate a carcinogen?
IARC classifies it as 'possibly carcinogenic to humans' (Group 2B): sufficient evidence in animals, inadequate evidence in humans. FDA maintains that properly baked bread contains only safe residue levels.
What is potassium bromate used for in bread?
It is a dough strengthener and flour-treating agent that helps dough hold its structure and rise.
Related ingredients
Sources
- eCFR (U.S. Government Publishing Office / National Archives) — eCFR :: 21 CFR 136.110 -- Bread, rolls, and buns. (accessed 2026-09-19)
- eCFR (U.S. Government Publishing Office / National Archives) — eCFR :: 21 CFR 172.730 -- Potassium bromate. (accessed 2026-09-19)
- U.S. FDA — List of Select Chemicals in the Food Supply Under FDA Review (accessed 2026-09-19)
- U.S. FDA — FDA Works to Enhance the Assessment of Ingredients in Foods and Food Contact Substances on the Market (accessed 2026-09-19)
- Government of Canada (Environment and Climate Change Canada / Health Canada) — Screening Assessment for the Challenge: Bromic acid, potassium salt (potassium bromate) (accessed 2026-09-19)
- European Union (EUR-Lex) — Regulation (EC) No 1333/2008 on food additives, consolidated text 02008R1333-20260818 (accessed 2026-09-19)
- IARC / NCBI Bookshelf — Potassium bromate - Some Chemicals that Cause Tumours of the Kidney or Urinary Bladder in Rodents and Some Other Substances (IARC Monographs Vol. 73) (accessed 2026-09-19)
- WHO / FAO JECFA — WHO | JECFA: Potassium bromate (accessed 2026-09-19)
- California Legislative Information — Bill Text - AB-418 The California Food Safety Act (Chapter 328, Statutes of 2023) (accessed 2026-09-19)
- New York State Senate — Kavanagh, Kelles, Healthy Food Advocates Announce Passage of Landmark Law to Require Disclosure of Chemical Ingredients and Safety Data for Processed Foods (accessed 2026-09-19)
- U.S. FDA — Substances Added to Food (formerly EAFUS): Potassium bromate (accessed 2026-09-19)
- eCFR (U.S. Government Publishing Office / National Archives) — eCFR :: 21 CFR 137.155 -- Bromated flour. (accessed 2026-09-19)
- Health Canada — 2. List of Permitted Flour Treatment Agents (Lists of Permitted Food Additives) (accessed 2026-09-19)
- New York State Senate — NY State Senate Bill 2025-S1239A: Enacts the 'food safety and chemical disclosure act' (accessed 2026-09-19)
This page summarizes what regulators and published research say, as of the review date above. Rules and evidence change; check the linked sources for the latest. It is general information, not medical advice — talk to a doctor or pharmacist about your own health.