Some science behind the scenes

Yellow food colouring - Quinoline yellow, Tartrazine and Sunset yellow

Tartrazine is a synthetic lemon yellow azo dye primarily used as a food colouring.  Quinoline Yellow is used as a greenish yellow food additive in certain countries, Sunset Yellow FCF is a petroleum-derived orange azo dye

  • Tartrazine has the E number E102, C.I. 19140, FD&C Yellow 5, Acid Yellow 23, Food Yellow 4, and trisodium 1-(4-sulfonatophenyl)-4-(4-sulfonatophenylazo)-5-pyrazolone-3-carboxylate).
  • Sunset yellow has the E number E110 (also known as Orange Yellow S, or C.I. 15985 and FD&C Yellow 6)
  • Quinoline Yellow is designated in Europe as the E number E104.

 

Tartrazine is a commonly used colour all over the world, mainly for yellow, and has also be used with Brilliant Blue FCF (FD&C Blue 1, E133) or Green S (E142) to produce various green shades.

Sunset Yellow is used in foods and condoms, cosmetics, and drugs. For example, it is used in candy, desserts, snacks, sauces, and preserved fruits. Sunset Yellow is often used in conjunction with E123, amaranth, to produce a brown colouring in both chocolates and caramel.  Sunset Yellow FCF was banned or restricted around year 2000 as a food additive in Norway, Finland and Sweden. 

Quinoline Yellow in the EU and Australia, Quinoline Yellow is permitted in beverages and is used in foods, like sauces, decorations, and coatings; Quinoline Yellow is not listed as a permitted food additive in Canada or the US, but it is permitted in medicines and cosmetics and is known as D&C Yellow 10

 An EU regulation came into effect in 2010 mandating that food manufacturers include a label on foods containing all three stating: "may have an adverse effect on activity and attention in children”.  Confused? - you should be.

Tartrazine can have serious health effects on human beings especially children, principally asthma and allergic reaction.  It is not clear how many individuals are sensitive or intolerant to tartrazine, but the University of Guelph estimates that it is 1 to 10 out of every ten thousand people (0.01% to 0.1% of the population). On the other hand, the prevalence of tartrazine intolerance in the USA is estimated at roughly 360,000 U.S. Citizens affected, around 0.12% of the general population. Perhaps it might be better to say it is actually a significant number, despite the attempts to hide it in percentages and that there is even more cause for concern because it is not known whether tartrazine has ill effects on individuals who are not clearly intolerant or even whether the allergies merely signal a far greater possible health hazard.

Several studies have linked the dyes to learning and concentration disorders in children, and there are a number of animal studies demonstrating potential risks such as kidney and intestinal tumours.  And the most concerning effects are those related to the unborn fetus

Tartrazine (TAZ) is one of the most commonly used artificial dyes for foods and drugs. We determined the effect of TAZ on fetal development by examining morphological, visceral, and skeletal malformations in rat fetuses following daily oral administration of TAZ to pregnant Wistar rats at the 6th-15th day of gestation. TAZ ….. induced fetal …..

  •  mortality,
  • lower body weight and length
  •  hepatic damage
  • destructed and necrotic renal tubules  
  • one or more missing coccygeal vertebrae
  •  missing sternebrae
  • missing hind limbs
  •  irregular ribs

We concluded that TAZ has embryotoxic and teratogenic potentials in rats. PMID: 30766659

Health problems

Tartrazine appears to cause the most allergic and intolerance reactions of all the azo dyes, particularly among asthmatics and those with an aspirin intolerance. Symptoms from tartrazine sensitivity can occur by either ingestion or cutaneous exposure to a substance containing tartrazine.

If cutaneous, a number of personal care and cosmetics products, for example, contain tartrazine.  Furthermore, other products, such as household cleaning products, paper plates, pet foods, crayons, inks for writing instruments, stamp dyes, face paints and envelope glues, may also contain tartrazine.

Symptoms appear after periods of time ranging from minutes up to 14 hours.   Total avoidance is the most common way to deal with tartrazine sensitivity.

Tartrazine is one of the most widely used artificial foods, drugs and cosmetic dyes. It is a nitrous derivative and is known to cause allergic reactions such as asthma and urticaria, as well as having been the focus of studies on mutagenesis and carcinogenesis due to its transformation into aromatic amine sulfanilic acid after being metabolized by the gastrointestinal microflora.  PMID:  17505761

Tartrazine is one of various food colours said to cause ADHD-like behaviour in children.   This list has been provided by the UK’s NHS:

Food colours and hyperactivity

The six food colours most closely linked to hyperactivity in children are:

  • E102 (tartrazine)
  • E104 (quinoline yellow)
  • E110 (sunset yellow FCF) 
  • E122 (carmoisine)
  • E124 (ponceau 4R)
  • E129 (allura red)

[Ref:  Sarah Chapman of Chapman Technologies on behalf of Food Standards Agency in Scotland. March 2011 [Guidelines on approaches to the replacement of Tartrazine, Allura Red, Ponceau 4R, Quinoline Yellow, Sunset Yellow and Carmoisine in food and beverages]

Sources of the chemicals

Processed commercial foods

Products containing tartrazine commonly include processed commercial foods that have an artificial yellow or green colour, or that consumers expect to be brown or creamy looking. It has been frequently used in the bright yellow colouring of imitation lemon filling in baked goods. The following is a list of foods that may contain tartrazine:

  • Desserts and confectionery: ice cream, ice pops and popsicles, confectionery and hard candy, cotton candy, instant puddings and gelatin (such as Jell-O), cake mixes, pastries, custard powder, marzipan, biscuits, and cookies.
  • Beverages: soft drinks, energy and sports drinks, powdered drink mixes, fruit cordials, and flavored/mixed alcoholic beverages.
  • Snacks: flavoured corn chips (such as Doritos, nachos, etc.), chewing gum, popcorn (both microwave and cinema-popped), and potato chips.
  • Condiments and spreads: jam, jelly (including mint jelly), marmalade, mustard, horseradish, pickles (and other products containing pickles such as tartar sauce and dill pickle dip), and processed sauces.
  • Other processed foods: cereal (such as corn flakes, muesli, etc.), instant or "cube" soups), rices (like paella, risotto, etc.), noodles, pureed fruit and pickled peppers, bright-green-coloured seaweed salad.

Medications

Quite astoundingly, various types of medications include tartrazine to give a yellow, orange or green hue to a liquid, capsule, pill, lotion, or gel, primarily for easy identification. Types of pharmaceutical products that may contain tartrazine include vitamins, antacids, cold medications (including cough drops and throat lozenges), lotions and prescription drugs.

Most, if not all, medication data sheets are required to contain a list of all ingredients, including tartrazine. Some include tartrazine in the allergens alert section.

Among 620 patients with urticaria, bronchial asthma or chronic rhinitis, oral provocation tests with ASS, tartrazine or benzoic acid revealed in 165 (26.6%) intolerance to ASS or additives. Frequency of intolerance to tartrazine varied between 6.1% in urticaria (n=308), 7.3% in asthma (n=96) and 14.5% in urticaria and asthma patients, while intolerance to benzoate varied from 2.5% in rhinitis (n=40) to 11.5% in asthma. More than two thirds of the intolerant patients were improved by an elimination diet and by the avoidance of "aspirin-like" drugs. More than one third of chronic urticaria patients became symptom free. In Switzerland exact declaration of all food additives is urgently needed. Moreover, azo-dyes must no longer be used for colouring of drugs. PMID: 7291963

Regulation

Regulation is haphazard.  Tartrazine is listed as a permitted food colouring in some countries, whereas in countries with a stronger emphasis on the precautionary principle, labelling is required.  At one stage, the UK FSA called for voluntary withdrawal of the colourings by food manufacturers. 

The European Food Safety Authority allows for tartrazine to be used in processed cheese, canned or bottled fruit or vegetables, processed fish or fishery products, and wines and wine-based drinks, although one can only assume this arbitrary list was devised under manufacturer pressure.

According to Wikipedia “The FDA regularly seizes products if found to be containing undeclared tartrazine, declared but not FDA-tested, or labeled something other than FD&C yellow 5 or Yellow 5. Such products seized often include noodles”, which says a great deal more about food manufacturers in the USA than it does the regulations, as seemingly they have no hesitation to add chemicals to their products that may cause death.

Ann Allergy. 1981 Feb;46(2):81-2.  Tartrazine (FD & C yellow #5) anaphylaxis: a case report.  Desmond RE, Trautlein JJ.  PMID:  7469134