EFSA Concludes Food Azo-Colours Unlikely to Trigger Adverse Reactions At Current Usage Levels

This opinion addresses the potential of individual food azo-colours, or their combinations, to cause intolerance and/or allergic reactions in humans after oral exposure, including the nature and prevalence of such adverse reactions.

Oct 12 2010 --- Following a request from the European Commission, a European Food Safety authority (EFSA) Panel on Dietetic Products, Nutrition and Allergies was asked to provide a scientific opinion, in the light of the most recent scientific evidence, on the appropriateness of the food azo-colours Tartrazine (E 102), Sunset Yellow (E 110), Carmoisine (E 122), Amaranth (E 123), Ponceau 4R (E 124), Allura Red AC (E 129), Brilliant Black BN (E 151), Brown FK (E 154), Brown HT (E 155) and Litholrubine BK (E 180) for inclusion in the list of food ingredients set up in Annex IIIa of Directive 2000/13/EC, as amended.

This opinion addresses the potential of individual food azo-colours, or their combinations, to cause intolerance and/or allergic reactions in humans after oral exposure, including the nature and prevalence of such adverse reactions. The potential of azo-colours to cause sensitisation following skin exposure is not addressed in this opinion.

Since the description of adverse reactions to the synthetic food colour Tartrazine over 50 years ago, a number of case reports have been published describing intolerance reactions. However, most published reports have been inadequately controlled, non-blinded and performed without an appropriate follow-up period to assess the effects of an exclusion diet, and therefore, it is uncertain whether the reported adverse reactions were indeed due to oral exposure to Tartrazine.

There is a shortage of large, well-controlled intervention studies with defined criteria following double-blind placebo-controlled food challenge (DBPCFC) principles which assessed the (adverse) effects of oral consumption of individual food azo-colours in humans. In addition, most of the studies designed to estimate the incidence of azo-colour intolerance have been conducted on selected patients with intolerance reactions in hospital settings, and no data are available with respect to the prevalence of intolerance to individual azo-colours in a non-selected general population. The frequency of Tartrazine intolerance has been estimated to be <1 % in subjects with food-induced urticaria and angioedema.

Only few cases of intolerance reactions to Tartrazine and Ponceau 4R, and to a lesser extent to Sunset Yellow FCF and Amaranth, in sensitive individuals have been reported following DBPCFC procedures after exclusion diets. These reactions include urticaria, angioedema, wheezing, and leukoclastic vasculitis. Intolerance reactions to Tartrazine have been observed at doses within the ADI (7.5 mg/kg bw/day), whereas the challenge doses of Ponceau 4R used in two-well documented cases of intolerance reactions to this colour were four to 10 times the ADI (0.7 mg/kg bw/day). No data on sensitivity to Brown FK, Brown HT, Litholrubine BK, Brilliant Black BN, Carmoisine, and Allura Red AC are available, and no well-documented cases of intolerance reactions after oral exposure have been reported. However, the absence of data on adverse clinical reactions after oral exposure could be due to the lack of clinical awareness of this possibility and subsequent underreporting.

Only few cases of intolerance reactions to colour mixtures including azo-dyes have been reported in sensitive individuals following DBPCFC procedures after exclusion diets. Intolerance reactions include urticaria, periorbital oedema, facial flushing, as well as higher hyperactivity scores in children.

The Panel concludes that it is unlikely that oral consumption of the food colours under consideration, either individually or in combination, would trigger severe adverse reactions in human subjects at the current levels of use.