Calcium peroxide

Calcium peroxide helps change dough structure during breadmaking. US standards limit it together with certain other oxidizers to 75 parts per million of flour; Canada permits up to 100 parts per million in bread under its combination rules. These are amounts used in flour, not measurements of what remains in a finished loaf. Direct evidence about long-term human exposure from treated bread is sparse.

JECFA reported insufficient toxicology data in its historical assessment and did not set a treatment level. Newer cattle-feeding experiments found changes in feed intake, digestion or rumen microbes at much higher, percent-level dietary inclusion, with differing results across studies. Those animal diets and digestive systems cannot be treated as a model of ordinary bread consumption. Concentrated calcium peroxide can irritate tissue, but handling hazards also do not establish injury from bakery use.

China revoked its food-additive permission from May 2011, explicitly citing lack of technological necessity. That legal restriction remains relevant, but does not by itself demonstrate a health hazard. The review considers missing dietary evidence and uncertainty about exposure, without claiming either proven harm or complete safety.

Research reviewed on September 5, 2026 · 10 sources