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What is Citrus Red 2? A Look at This Food Dye and Potential Health Issues

Written By
Erin Coleman
RD

Why This Was Updated?

Our specialists regularly review advancements in health and wellness, ensuring our articles are updated with the newest information as it becomes accessible.
Medically Reviewed by
Updated On
August 9, 2024

Food dye use in the food industry is abundant, as many manufacturers color foods to improve their appearance and appeal to consumers. While food dyes are widely popular in the food industry, Citrus Red 2 and other dyes are of concern because of their negative effects on animal studies and potential harm to humans, such as cancer and worsening ADHD symptoms.

This article explores Citrus Red 2, which foods contain it, why this dye is used, and potential safety concerns or health issues associated with orange-colored food dyes.Β 

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Understanding Citrus Red 2

Citrus Red 2 is a U.S. Food and Drug Administration (FDA)-approved food dye. The chemical makeup of Citrus Red 2 is 1-(2,5-dimethoxyphenyl azo)-2-naphthol. It appears as a dark red powder or orange-to-yellow solid, making it a desirable food dye for some citrus fruit manufacturers.Β 

History and Approval

Citrus Red 2 was designed as a dye to color citrus fruits, particularly oranges.Β 

The FDA allows Citrus Red 2 to be used only for:

  • Coloring the skins of oranges that are not used for processing.
  • Orange peel coloring that doesn’t contain more than 2 ppm (parts per million) of color additive based on the weight of the fruit.Β 
  • Orange skin coloring that meets minimum maturity standards established by the state in which the oranges are grown.

Citrus Red 2 is created by commercially coupling the diazotization (chemical reaction) of 2-naphthol with 2,5-dimethoxyaniline.

Uses of Citrus Red 2

Citrus Red 2 has the following uses:

Primary Uses in Food

Oranges, particularly Florida oranges, may contain Citrus Red 2 on the peel to improve their aesthetic appeal to consumers. This use of this dye is decades old, resulting from the weak natural color of certain varieties of oranges and hybrids grown in Florida.Β 

Some packinghouses apply Citrus Red 2 dye to orange peels to improve the surface color before applying fruit wax to retain moisture and enhance shine.Β 

Other Uses

The only FDA-approved use of Citrus Red 2 is to alter the color of orange peels. It’s not approved for use in consumable foods. However, similar orange and red food dyes are approved for use in edible foods. These dyes also pose concerns about potential adverse health effects.Β 

Health Concerns Associated with Citrus Red 2

Citrus Red 2 has been the subject of significant health and regulatory scrutiny due to its potential risks and carcinogenic properties.

Potential Health Risks

Potential health risks are associated with consuming Citrus Red 2 food dye, as toxicity tests on this orange dye suggest safety concerns. The researchers determined that because Citrus Red 2 doesn’t improve the nutritional quality or safety of foods, it should be removed from the food supply or replaced with safer alternatives.Β 

The Center for Science in Public Interest determined that Citrus Red 2 causes bladder tumors in mice and rats. Researchers found a link between Citrus Red 2 and brain and urinary bladder tumors.Β 

Studies also show that artificial food coloring appears to affect children’s behavior, particularly those with ADHD. The researchers suggest significant increases in the consumption of artificial food dyes each decade.Β 

Additional research found that synthetic dyes are linked to hyperactive behaviors in children, worsening symptoms of ADHD, and potentially autism spectrum disorder.Β 

The International Programme on Chemical Safety and World Health Organization determined that high doses of 200 mg/kg/day of Citrus Red 2 in dogs led to decreased activity, poor appetite, and increased total leukocytes (white blood cells).Β 

Regulatory and Scientific Perspectives

The FDA allows Citrus Red 2 to color the skins of mature oranges in amounts equal to or less than 2 ppm by weight of the whole fruit. However, the FDA has only approved Citrus Red 2 for orange peels, not for use on the edible portion of oranges.

According to the Joint FAO/WHO Expert Committee on Food Additives (JECFA), Citrus Red 2 has carcinogenic (cancer-causing) activity, and the toxicological data available is inadequate to determine a safe upper limit.

The International Programme on Chemical Safety and World Health Organization advise that Citrus Red 2 not be used as a food additive because of its negative effects on rats, mice, and dogs in animal studies.Β 

While Citrus Red 2 is allowed for use on orange peels in the United States, it’s use is not permitted in the European Union (EU). The EU classifies Citrus Red 2 as a group 2B carcinogen (cancer-causing substance). The International Agency for Research on Cancer (IARC) also places Citrus Red 2 in Group 2B (possibly cancer-causing to humans).

Public and Expert Opinions

Public and expert opinions on Citrus Red 2 reveal significant concerns about its safety and the potential health risks associated with its continued use in the food industry.

Consumer Awareness and Concerns

Sacred Heart University reports that many FDA-approved food dyes, including Citrus Red 2,Β  raise concerns among health professionals. This University confirms that Citrus Red 2 is toxic in rodents and that humans and rodents have similar brain functions and structures.Β 

The FAO/WHO Expert Committee on Food Additives agrees that Citrus Red 2 should not be used in foods.

The Center for Science in the Public Interest reports that Citrus Red 2 is toxic in rodents at modest levels, causing tumors in the urinary bladder and possibly other organs. This agency also suggests that Citrus Red 2 should not be in the food supply.

The Center for Science in the Public Interest notes that Citrus Red 2 is a human health hazard because it can be ingested from the fingers after peeling an orange treated with dye. This group also reports that Citrus Red 2 use may violate the Federal Food, Drug, and Cosmetic Act prohibiting carcinogenic color additives that result in ingesting cancer-causing dyes.Β 

The California Office of Environmental Health Hazard Assessment (OEHHA) lists Citrus Red 2 as a cancer-causing substance.Β However, despite these cautions and the continued use of Citrus Red 2 to color orange peels, many consumers don’t realize the oranges they purchase contain potentially cancer-causing chemicals.Β 

To avoid consuming Citrus Red 2 via orange peels, particularly when using grated orange peels in recipes, choose organic oranges or shop at your local farmer’s market.Β 

Expert Opinions

Many health experts agree that food dyes may have negative physical and mental health consequences.Β  For example, the joint FAO/WHO expert committee on food additives suggests that on the basis of toxicological evidence, Citrus Red 2 is unsafe for use in foods.

The reason food industry experts continue to use Citrus Red 2 is to increase consumer appeal and the purchase and consumption of oranges. The health benefits of oranges and other citrus fruits are abundant because of their anti-inflammatory, anti-cancer, anti-oxidative properties and protection from neurodegeneration, heart disease, and other diseases.Β 

Alternatives to Citrus Red 2

In light of the health concerns surrounding Citrus Red 2, exploring safer and more natural alternatives is crucial for both consumer safety and industry standards.

Natural Alternatives

Natural alternatives may be available to replace Citrus Red 2. Researchers found that annatto and paprika extracts are natural colorants comparable to Citrus Red 2 for creating the same moisture retention, shine, internal gas content, color, respiration rate, and other qualities.Β Β 

The University of Florida confirms that paprika, paprika oleoresin, and annatto extract are suitable natural alternatives to Citrus Red 2, with annatto being the most effective. These natural dyes are likely safer than Citrus Red 2.Β 

Carrot oleoresin and Ξ²-carotene were also tested as natural alternatives to Citrus Red 2; however, they produced a color that was too light for industry standards.Β 

Natural alternatives for red dye include pomegranate juice, beet powder, beet juice, cranberries, cherries, strawberries, and dried hibiscus flowers.Β 

Synthetic Alternatives

Citrus Red 2 is currently the only FDA-approved dye for orange peel coloring.

However, Orange B was approved for use on the surface of sausages and frankfurters in amounts of up to 150 ppm by weight. Red 3 and Red 40 are red dyes approved for use in foods.Β 

For example, the FDA approved Red 3 for beverages, cereals, confections, ice cream cones, popsicles, frostings, icings, and frozen dairy desserts. Red 40 is FDA-approved for cereals, gelatins, puddings, beverages, dairy products, and confections.Β 

However, the Center for Science in the Public Interest and 23 additional organizations urge the FDA to remove red dyes from approved foods, medicines, and supplements because studies have found benzidine and other carcinogens in Red 40 and other food dyes.

The regulatory approval process for safe alternatives to Citrus Red 2 in the U.S. includes a petition for using color additives addressed by the FDA’s scientists. The FDA deems a color additive safe if there is convincing evidence that the color won’t cause harm when used in the intended way.Β 

A petition for amendment or new application is necessary if the manufacturing process or intended food additive use changes.

While no additive that causes cancer in animals or humans is considered safe, Citrus Red 2’s intended use for coloring non-edible orange peels means it is not meant to be ingested.Β 

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Key Takeaways

  • Citrus Red 2 is a food dye used to color the peel of some oranges, particularly Florida-grown oranges, to improve consumer appeal and orange consumption.
  • While oranges are highly nutritious, Citrus Red 2 used to color the peel has caused cancer in animal studies and behavior changes in humans, particularly those with ADHD.
  • Concerns about Citrus Red 2 arise because of the potential to ingest food dye after touching the peel and then touching the edible part of the orange. Select organic oranges whenever possible.
  • It’s important to stay informed about food additives to make educated decisions about their consumption.Β 
The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.
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