JECFA could not set a safe daily intake
The Joint FAO/WHO Expert Committee on Food Additives (JECFA) evaluated Ponceau 6R multiple times between 1959 and 1977 and concluded it was not possible to establish an acceptable daily intake on the data available. The long-term animal studies that were conducted were described by JECFA as inadequate: they focused narrowly on carcinogenicity, used small numbers of animals, and lacked data on metabolism, reproduction, and embryotoxicity. JECFA withdrew its specifications for this additive in 1984.
JECFA evaluated Ponceau 6R in 1974 and recorded 'No ADI allocated - not possible on the data provided', citing absent metabolic data, inadequate animal numbers, and missing reproduction studies.
1974Regulatory reviewJECFA, WHO Food Additives Series 6 (Monograph 380, Ponceau 6R)
At its 1977 meeting JECFA deferred a decision on Ponceau 6R again, and the specifications were formally withdrawn in 1984, indicating the additive was removed from consideration for food use.
1977RegulatoryJECFA Evaluations Database, inchem.org (Ponceau 6R, TRS 617-JECFA 21)
Removed from EU and UK permitted colours lists in 1994
When the European Community replaced its original 1962 colours directive with Directive 94/36/EC on colours for use in foodstuffs, Ponceau 6R was one of seven artificial colours deleted from the positive list. The deletion was based on the Scientific Committee on Food's ongoing review of toxicological data. The UK's Colours in Food Regulations 1995, which implemented the directive domestically, did not include E126. Current UK law (assimilated EU Regulation 1333/2008) does not list E126 as a permitted food colour.
Ponceau 6R was among seven artificial colours (alongside Chrysoine S, Fast Yellow AB, Orange GGN, Scarlet GN, Anthroquinone Blue and Black 7984) deleted from the EU positive list when Directive 94/36/EC replaced the 1962 colour directive, based on the Scientific Committee on Food's toxicological evaluation.
1994RegulatoryNATCOL (Natural Food Colours Association), Food Colours Legislation review; EU Directive 94/36/EC
E126 does not appear in the UK FSA's current approved additives and E numbers list, nor in the schedule of permitted colours in the UK's assimilated food additives legislation.
RegulatoryUK Food Standards Agency, Approved Additives and E Numbers (food.gov.uk)
Azo dye class: aspirin sensitivity and potential reactions
Ponceau 6R belongs to the azo dye class. Azo dyes are metabolised in the gut to aromatic amine breakdown products. In people who are sensitive to aspirin or non-steroidal anti-inflammatory drugs, azo dyes as a class have been reported to trigger asthma, urticaria and other reactions, though controlled challenge studies suggest confirmed reactions are far less common than patients report. The JECFA monograph specifically noted that sensitivity reactions had been reported in people allergic to benzoates and aspirin.
The JECFA monograph on Ponceau 6R recorded that sensitivity reactions in people allergic to benzoates and aspirin had been reported (citing Michaelson and Juhlin, 1973).
1974ObservationalJECFA, WHO Food Additives Series 6 (Monograph 380, Ponceau 6R)
A controlled oral challenge study found that confirmed hypersensitivity to azo dyes in urticaria patients is much less common than patient self-report suggests, with only around 5% of challenged patients showing a positive reaction.
2022RCTMlynek et al., Hypersensitivity of azo dyes in urticaria patients (PMC9704453)
Azo dyes as a class are metabolised by intestinal microflora to aromatic amines, which are further activated by liver enzymes and have potential genotoxic properties in laboratory models.
1992LabMutagenicity of azo dyes: structure-activity relationships, Food and Chemical Toxicology (PMID 1381050)
Animal study findings were limited and carcinogenicity-focused
The long-term animal studies conducted on Ponceau 6R were designed only to detect carcinogenicity and used small animal numbers. One rat developed a tumour of possible pancreatic origin in a dietary study, but JECFA judged the evidence insufficient to draw conclusions. The studies were not structured to detect organ toxicity broadly. Claims that animal studies showed serious disorders of the liver, kidneys, ureters and bladder circulate in some secondary sources but are not supported by the primary JECFA monograph text, which reports no such findings and explicitly describes the studies as inadequate.
JECFA's 1974 monograph noted that long-term studies with Ponceau 6R 'aimed solely at discovering potential carcinogenicity and therefore did not include the detailed observations usually made in these tests,' and that the small animal numbers made them inadequate for assessing long-term toxicity.
1974AnimalJECFA, WHO Food Additives Series 6 (Monograph 380, Ponceau 6R)