The safety of 5-bromo-5-nitro-1,3-dioxane has been assessed by Expert Panel for Cosmetic Ingredient Safety. The Expert Panel evaluated the scientific data and concluded that 5-bromo-5-nitro-1,3-dioxane was safe as a cosmetic and personal care products ingredient at concentrations up to and including 0.1%, except under circumstances where its action with amines or amides can result in the formation of nitrosamines or nitrosamides. In 2007, as part of its regular re-review of cosmetic ingredients, the Expert Panel considered available new data on this ingredient and reaffirmed the above conclusion.
5-Bromo-5-nitro-1,3-dioxane can be metabolized to 2-bromo-2-nitropropane-1,3-diol, a nitrosating agent, that has also been reviewed by the Expert Panel and found safe for use in cosmetic and personal care products. At concentrations of 0.5% and above, 5-bromo-5-nitro-1,3-dioxane has been shown to be a skin and eye irritant but is neither a sensitizer nor a photosensitizer. This ingredient was neither mutagenic nor a developmental toxicant. Sensitization was observed in patients at 0.1% and 0.5%, but not in a study on volunteers. The Expert Panel concluded that 5-bromo-5-nitro-1,3-dioxane can be safely used in cosmetic and personal care products at concentrations up to and including 0.1%, except when it may react with amines and amides to form nitrosamines or nitrosamides.
5-Bromo-5-nitro-1,3-dioxane may be used as a preservative in rinse-off cosmetics and personal care products marketed in the Europe at concentrations up to 0.1% (see Annex VI). The formation of nitrosamines must be avoided.
In Canada, 5-bromo-5-nitro-1,3-dioxane may be used in cosmetics and personal care products at a maximum concentration of 0.1%.