Statement on the validity and robustness of information provided on irradiated iron oxides

Following a Rapid Alert System for Food and Feed (RASFF) notification concerning the use of an unauthorised irradiated colouring agent (brown iron oxide) as coatings of food supplements, the European Commission asked EFSA to assess the scientific validity and robustness of three documents i) two safety assessments from two pharmaceutical companies including information on the manufacturing process of iron oxides, and ii) one safety assessment on gamma irradiated iron oxides in food supplements provided by a consultant. According to the supplier of iron oxides and hydroxides (E 172), the aim of the ⁶⁰Co-gamma irradiation treatment was to eliminate microbiological contamination. Iron oxides and hydroxides (E 172) are authorised food additives in the EU. EFSA noted that the gamma irradiation of iron oxides (yellow, red, black and brown) has not been previously evaluated by other Scientific Committees dealing with foodstuffs, pharmaceutical products or cosmetics and that the irradiation doses applied to iron oxides in this particular case are higher than the doses currently authorised in the EU for “other food and food ingredients”. EFSA also noted that some evidence is available in the literature demonstrating a reduction of iron(III) to iron(II) due to ⁶⁰Co-gamma irradiation and, that the food additive black iron oxide, as authorised in the EU, contains iron in both (II) and (III) valence states. Therefore, an increase in the content of divalent iron would not be of safety concern per se. However, EFSA also notes that the information on irradiated iron oxides provided is very limited and insufficient to substantiate the claim that iron oxides are not expected to undergo any chemical transformation upon irradiation. In order to demonstrate the chemical stability of iron oxide during the ⁶⁰Co-gamma irradiation treatment, EFSA recommends to carry out some further analyses.