The Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food has been asked to review the toxicological data on a number of dyes illegally present in foods in the EU.The Panel also offers advice on ways of identifying dyes which have structural alerts for genotoxic and carcinogenic properties. Following the first report in 2003 of the illegal presence of the dye Sudan I in some foods in the European Union (EU), there have been many notifications by EU Member States of the presence of this and other illegal dyes in chilli powder, curry powder, processed products containing chilli or curry powder, sumac, curcuma and palm oil. The dyes concerned are Sudan I, Sudan II, Sudan III, Sudan IV, Para Red, Rhodamine B and Orange II. The available toxicity data on these seven dyes (see Annex 1 to the opinion) have been reviewed. The Panel concluded that there are insufficient data on any of the illegal dyes, Sudans I-IV, Para Red, Rhodamine B, and Orange II, found so far in foods in the EU to perform a full risk assessment. However, there is experimental evidence that Sudan I is both genotoxic and carcinogenic and that Rhodamine B is potentially both genotoxic and carcinogenic. For the following dyes, conclusive evidence is lacking but, because of structural similarities to Sudan I, it would be prudent to assume that they are potentially genotoxic and possibly carcinogenic: Sudan II, Sudan III, Sudan IV, Para Red. For Orange II genotoxicity cannot be ruled out and the existing data on carcinogenicity are inadequate for any conclusion. In order to offer some guidance on structural features of dyes that may provide alerts for possible genotoxic and carcinogenic activity, the Panel reviewed information from the literature on other genotoxic and/or carcinogenic industrial dyes, not hitherto found in food, (see Annex 2 to the opinion) has been reviewed. This information, together with consideration of structure-activity relationships indicates that dyes with azo, triphenylmethane and anthraquinone structures should initially be considered suspect. Among the azo dyes, the potential to be metabolised to lipidsoluble aromatic amines, in particular benzidine derivatives, is an alert for genotoxicity/carcinogenicity, while sulphonation of all ring components, as is the case in most of the azo dyes approved as food colours in the EU, eliminates genotoxic and carcinogenic activity. Consideration of reports of dyes that have been used illegally in countries from which spices originate and dyes that have been used in the past as food colours in other countries but withdrawn from food use following discovery of toxicity, together with laboratory studies and structure activity considerations suggest that the following dyes should be viewed as genotoxic and/or carcinogenic: Acid Red 73 (CAS-No. 5413-75-2), Sudan Red 7B (CAS-No 6368-72-5), Metanil Yellow (CASNo 587-98-4), Auramine (CAS-No 492-80-8), Congo Red (CAS-No 573-58-0), Butter Yellow (CAS-No 60-11-7), Solvent Red I (CAS-No 1229-55-6), Naphthol Yellow (CAS-No 483-84-1), Malachite Green (CAS-No 569-64-2), Leucomalachite Green (CAS-No 129-73-7), Ponceau 3R (CAS-No 3564-09-8), Ponceau MX (CAS-No 3761-53-3), Oil Orange SS (CAS-No 2646-17-5) A number of other withdrawn food dyes had inconclusive evidence of genotoxicity and this may be related to the poor specification of the dyes tested in early studies, since structure-activity analysis would not suggest these properties.
