Potassium bromate
A flour treatment agent that IARC classes as possibly carcinogenic to humans. Not permitted in the EU; still allowed in some countries.
- Category
- Flour treatment agents
- Vegan
- Yes
- Vegetarian
- Yes
What it is
A powerful flour bleaching or oxidizing agent used to artificially age and whiten flour. (Often listed interchangeably with E924).
How it is used in food
Forces flour to instantly 'mature' and turn pure white, allowing bakeries to skip the natural aging process.
Commonly found in- Commercial bread (in permitted countries)
Health and safety
Caused kidney and thyroid tumours in animal studies, which is why IARC places it in Group 2B, possibly carcinogenic to humans. Most of it breaks down during baking, but residues can remain.
Evaluated by food safety authorities and determined to be unsafe for general food use.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| Australia & New Zealand FSANZ |
Banned | Banned due to carcinogenic concerns. |
| European Union EFSA / European Commission |
Not approved | Not on the EU authorised list of food additives (Annex II). |
| United States FDA (Food and Drug Administration) |
Permitted | Permitted in the US as a dough conditioner, despite bans in other regions. |
Identification on labels
- E-number
- E924a
Worth knowing
It acts identically to E924 and is functionally the same additive designation in many regions.
Conclusion
A carcinogenic dough conditioner banned in most of the world.
References
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Open the appEntry last reviewed 2026-08-05.
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