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Acid Yellow 9

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A representation of E105

Acid Yellow 9 is a yellow azo dye that is used in many areas. But how does it affect dogs and is it harmful or even dangerous? In this article, you can find out more about this ingredient and its advantages and disadvantages.

What is Acid Yellow 9?

Acid Yellow 9 is a synthetic dye that consists of two benzene rings that are connected to each other via an azo group (=N=N). In addition, two sulfonic acid groups (=SO3H) and an amino group (=NH2) are attached to the rings. The dye has the molecular formula C12H9N3Na2O6S2 and the CAS number 2706-28-7.

Acid Yellow 9 was discovered in 1860 by the German chemist Peter Grieß when he allowed nitrous acid to act on an alcoholic solution of aniline. He named the substance "diazoamidobenzene" and discovered that it was explosive. It later turned out that it was an azo dye that could be used to dye wool.

Where is Acid Yellow 9 used?

Acid Yellow 9 belongs to the group of acid dyes that combine well with animal fibers such as wool or silk. The dye has a high light fastness, which means that it does not fade so quickly when exposed to sunlight. It is therefore mainly used for dyeing textiles.

Acid Yellow 9 was previously also used as a food colorant under the name E 105, but was banned in the EU at the end of 1976. The reason for this was that the dye was suspected of being carcinogenic. Today, Acid Yellow 9 is still used as a cosmetic colorant, for example in hair dyes or nail polishes. It is also used as a starting material for the production of other azo dyes such as Acid Red 66 or Acid Red 112.

How does Acid Yellow 9 affect dogs?

There are no specific studies on the effects of Acid Yellow 9 on dogs, but some evidence from other sources suggests that the dye is not harmless to dogs.

For one thing, it is known that azo dyes in general can trigger allergic reactions, especially in people with an aspirin intolerance. Symptoms can include skin rashes, itching, breathing difficulties or asthma. It is therefore possible that dogs may also react sensitively to Acid Yellow 9 if they ingest it through the skin or with food.

On the other hand, it is known that azo dyes can be broken down in the body into aromatic amines, which are potentially carcinogenic. This occurs primarily in the intestine by the bacterial flora or in the liver by enzymes. It is therefore possible that dogs also have an increased risk of cancer if they ingest Acid Yellow 9 over a longer period of time.

Acid Yellow 9 is a yellow azo dye that is used for dyeing textiles or cosmetics. It has a high light fastness and a bright color. It was previously also used as a food colorant, but is banned in the EU because it can be carcinogenic. Acid Yellow 9 is not safe for dogs as it can cause allergic reactions or cancer. It is therefore recommended that products containing Acid Yellow 9 are avoided or at least used with caution.

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If you notice any signs of hypersensitivity or poisoning in your dog, you should see your vet immediately. We are not a substitute for a vet, but we try to be as accurate as possible. Every dog reacts differently and we recommend you get a second opinion or consult your vet if in doubt.

Stay healthy and take good care of your four-legged friend!😊

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