Ultra-processing markers
Potassium bromate
Definition
What it is
Bleached or bromated flour: treated with chemical agents; potassium bromate is classified as a possible human carcinogen (IARC Group 2B) and is banned in the EU, Canada, and Australia.
On the label
How it appears on labels
- potassium bromate
- bromated flour
Regulation
Regulatory status
- Australia/NZ Banned
- Brazil Banned
- Canada Banned
- European Union Banned
- Japan Banned
- United Kingdom Banned
Explainer
In plain language
Potassium bromate is a flour-treatment agent added to some breads and baked goods to strengthen dough and help loaves rise higher and more evenly. It works as an oxidizing agent during mixing and baking. When baking is done correctly, most of it is meant to convert into bromide, but small residues can remain in the finished product.
Assessment
Why it is flagged
The International Agency for Research on Cancer classified potassium bromate as possibly carcinogenic to humans (Group 2B), based largely on animal studies that observed tumors in rats. On that basis it is banned from food use in the European Union, Canada, and Australia, and its use is restricted in several other countries. In the United States the FDA has not banned it, though California's Food Safety Act, signed in 2023 and taking effect in 2027, prohibits it in foods sold in that state. The concern centers on residual bromate left in bread when baking does not fully convert the additive. Clear Label marks this high severity because major regulators disagree, with several having removed it from the food supply entirely.
In the aisle
Where it commonly shows up
- Commercial white and sandwich breads
- Bread rolls and buns
- Bagels
- Pizza dough and flatbreads
- Some bakery flour sold to businesses
Practical
Reading the label
On US labels look for 'potassium bromate' or 'bromated flour' in the ingredient list. Products that avoid it sometimes state 'unbromated flour' on the package. It is most common in mass-produced bakery goods rather than in flour sold in bans that ban it.
Alternatives
If you want to avoid it
Some people choose breads and flours labeled 'unbromated' or products from regions where the additive is banned. Many artisan and organic bakeries do not use bromated flour at all.
FAQ
Common questions
Is potassium bromate banned in the United States?
Not nationally. The FDA still permits it, though California passed a law in 2023 banning it in foods sold in the state starting in 2027. It is banned in the European Union, Canada, and Australia.
Why do some countries allow it and others ban it?
Regulators weigh the same animal carcinogenicity data differently. The EU, Canada, and Australia chose to prohibit it as a precaution, while the FDA has continued to permit it with the expectation that proper baking converts most of it.
Can baking remove potassium bromate?
Baking is meant to convert most of it into bromide, but the concern is that residual bromate can remain when conditions are not ideal. This uncertainty is part of why several countries removed it from food use.
Citations
Sources
Citation
Primary reference
About this page: the definition, label names, severity, and regulatory chips come from the clearlabel ingredient taxonomy, the same data the scanner uses to score products. Research summaries describe associations reported in published studies, not diagnoses; individual responses vary. Scan any product with clearlabel to see which of its ingredients carry flags.