The Potential Risks of Tartrazine

Tartrazine, also referred to as FD&C yellow #5, is an artificial (synthetic) food dye. It is one of several azo food dyes that are made from petroleum products.

Artificial food dyes are used to make foods more aesthetically appealing from a visual standpoint. These dyes can be used to create colors not possible with natural products as well as to reinstate the original appearance of a food which may be lost in the production process. Artificial food dyes are also often cheaper and more accessible than natural food dyes.

It's important to note that food dyes are present not only in foods but can be found in cosmetics and other products, and some absorption through the skin occurs.

Adverse Reactions to Tartrazine

Tartrazine has long been suspected of being the cause of many adverse reactions, though not all have been supported by research. Some suspected reactions include:

• Urticaria (hives)
• Angioedema (swelling of the lips, tongue, throat, and neck caused by the release of histamine in an allergic reaction)
• Asthma
• Atopic dermatitis (skin rashes related to allergies)
• Food intolerances

The most recent research found that less than 1 percent of allergic patients (those who already have multiple allergies) reacted when tested for their response to tartrazine. There has also been a theory that aspirin-sensitive asthmatics may be especially sensitive to tartrazine, but this theory appears to be largely disproven based on more recent studies.

Other Concerns Related to Tartrazine

Certainly, there have been studies which have looked at other possible concerns with tartrazine added to food dyes or it would not be available in commerce. Those which have looked more closely at genotoxicity (the ability to be toxic to genes), cytotoxicity (the ability of a substance to be toxic to cells), and mutagenicity (the ability of a substance to cause gene mutations) may be unsatisfactory.

Unfortunately, many of the studies to date have been done on rats, so we are unsure what meaning these have with regards to humans. Given that azo food dyes such as tartrazine have been banned in many countries, it's important to consider the possible reasons behind these bans based on what we have learned.

Tartrazine as a Neurotoxin

Tartrazine appears to be a neurotoxin (toxic to cells in the brain) at least in rats. It's thought that tartrazine affects the nervous system in rats in ways that include problems with spacial memory and more. This appears to be significant enough that tartrazine has been tested along with other agents to see if these other agents may play a protective role against damage to the nervous system caused by tartrazine. For example, a 2017 study found that administering vitamin E (a neuro-protective agent) might prevent both the structural and behavioral changes caused by tartrazine—at least in rats.

Rats that were given tartrazine have a number of findings in their central nervous system, including a shortage of brain neurotransmitters. Increased cell death in the brain was also noted. It is not known if these changes also pertain to humans.

Behavior Problems in Children

Whether tartrazine could cause behavioral changes in human children similar to rat progeny haven't been assessed directly to the same degree, but a few studies have been done. Studies looking specifically at the use of artificial food colorings in children have found that large doses (defined as 50 mg or more of AFC) caused a greater negative effect on children than those who received less.

Those who raise concern mention that the use of synthetic food dyes has increased by 500% in the past 50 years, at the same that behavioral problems such as ADHD have been increasing. Yet there are many, many changes that have occurred during this time period beyond the adoption of artificial food dyes, and this correlation, as well as a whole host of other possible links, are mostly conjecture.

Tartrazine as a Carcinogen

One study looking at DNA repair found that tartrazine had no cytotoxic effects, but did have significant genotoxic effects at all concentrations studied.

It's important to note that even when our DNA is damaged, we have many repair systems (such as proteins coded for within tumor suppressor genes) which can fix this damage. In the study looking at tartrazine, it was found that most of the damage was amenable to repair, but that some damage did persist in specimens exposed to tartrazine, unlike those not exposed, even 24 hours after exposure. The conclusion was that prolonged exposure to tartrazine could trigger carcinogenesis.

Tartrazine During Pregnancy

Again, we don't know much about the possible effects of prenatal exposure to artificial food colorings, but several studies have found some problems, such as a decrease in motivation and anxiety in offspring of rats exposed during pregnancy.

This does not mean that there is a potential for problems in human infants. Rats and humans are obviously different. There are some substances that cause problems in rats but not in humans and vice versa. What these animal studies suggest, however, is that it is important to further study this issue until more is known.

Tartrazine-Free Diet and Labeling

The following is a list of foods that often contain tartrazine. While many products are labeled, others, such as ice cream and desserts, are not always labeled as containing tartrazine.

• Certain breakfast cereals
• Refrigerated rolls and quick breads
• Cake mixes
• Commercial pies
• Commercial gingerbread
• Butterscotch chips
• Commercial frostings
• Certain instant and regular puddings
• Certain ice creams and sherbets
• Certain candy coatings
• Hard candies
• Colored marshmallows
• Flavored carbonated beverages
• Flavored drink mixes

Food Dyes Used in Commerce

In addition to tartrazine, other synthetic colorants are getting more attention.

Dyes that are defined as azo food dyes, in addition to tartrazine (FD&C yellow #5), include:

• Quinoline yellow
• Sunset yellow
• Axorubine
• Ponceau 4R
• Erythrosine
• Allura Red
• Patent blue
• Indigo carmine
• Brilliant blue FCF
• Green S
• Brilliant black
• Brown HT