Dog Shampoo: These Contain Unwanted Chemicals
Gå til hovedindhold

Få adgang til hele tæ

Bliv medlem

Dog Shampoo: These Contain Unwanted Chemicals

We've tested 29 dog shampoos for your furry friend for chemicals that, among other things, can cause allergies. See which substances you should avoid here.

Katja Laukkonen Ravn · 8. april 2024

When you wash your dog with dog shampoo, both you and your furry friend can come into contact with chemicals that can cause allergies.  

We have also found suspected endocrine disrupters or environmentally harmful substances in some dog shampoos. 

Our test also shows that you can easily find dog shampoos that are free from a range of problematic chemicals. 

We tested the chemical content of dog shampoo in the same way as we test eg cosmetics and personal care products for unwanted chemicals. This means that we focus on the possible effects of the substances on the people who use the products. 

Avoid These Substances in Dog Shampoo  

11 out of 29 dog shampoos contain problematic chemicals. The most common ones are the ic preservatives known as isothiazolinones that can cause allergy. 

In the test, the substances are found under the names benzisothiazolinone, methylchloroisothiazolinone, methylisothiazolinone (MI), and menzisothiazolinone. 

These are long and difficult names to remember, but a good rule of thumb is to avoid dog shampoos with substances ending in “isothiazolinone” on the ingredient list. 

These substances are known to potentially cause lifelong allergies. The compound MI, for instance, can trigger allergies even in very small amounts. 

In the test, we also found perfumes that can cause allergies, and the substances BHA and benzophenone-4, which are suspected of being endocrine disruptors. 

Is Dog Shampoo the Same as Regular Shampoo?  

Dog shampoo and regular hair shampoo for humans are not the same. 

Dogs' skin is more alkaline than human skin, which is why dog shampoo is different from hair shampoo and soap for humans. Many veterinarians advise against washing your dog with shampoo and soap designed for human skin. 

It is not recommended to use human shampoo for your dog. Your dog's skin can react differently than your own when exposed to shampoo designed for humans. Mette Schjærff PhD, Associate Professor, and Head of Dermatology Services at the University Hospital for Companion Animals at the University of Copenhagen.

"It is not recommended to use human shampoo for your dog. Your dog's skin can react differently than your own when exposed to shampoo designed for humans," says Mette Schjærff, PhD, Associate Professor, and Head of Dermatology Services at the University Hospital for Companion Animals at the University of Copenhagen. 

Is Dog Shampoo Necessary?  

Even when using dog shampoo, Mette Schjærff says it's generally not necessary to wash your dog frequently. 

"We are used to taking showers daily and often using shampoo. I understand why dog owners might want to wash their dogs with shampoo once in a while, like after a trip to the beach or the woods, especially if the dog has rolled in something that smells bad. But other than that, generally healthy dogs don't need frequent baths," she says, explaining further: 

"If you wash your dog frequently with dog shampoo, it can strip the natural oil from the dog's skin and remove good bacteria from the skin surface, which helps maintain a normal skin ecosystem." 

It's important to distinguish between dogs with normal skin and those with skin issues, such as allergies or excessive sebum production, where special dog shampoos are a key part of treatment. 

"If your dog has allergies, oily skin, or other skin issues, that's a different story. Here, medicated dog shampoos or shampoos targeted at specific skin needs, which veterinarians recommend as an important part of treatment, are beneficial" says Mette Schjærff. 

In general, Mette Schjærff's recommendation is to avoid dog shampoos with perfume and to watch out for allergic reactions in connection with using dog shampoo. This applies to both your exposure and your dog's exposure to perfume and other allergenic substances. 

"If you're unsure about how your dog will react to the shampoo, it's recommended to try it on a smaller area first to see if the dog can tolerate it. Additionally, as a dog owner, remember that you are also exposed to the shampoo, so if you suffer from allergies, it might be beneficial to wear gloves," she concludes. 

Dog Shampoo Is Not a Cosmetic Product  

Regular hair shampoo is a cosmetic product with certain requirements for chemicals and labeling. The same does not apply to dog shampoo. 

Dog shampoo is a chemical product, similar to e.g. paint, where there's no requirement to list all ingredients on the product and not similar   legal restrictions on chemicals as if it was a hair shampoo. 

In our test, we find, for example, the allergenic preservative benzisothiazolinone in one of the dog shampoos, which is not allowed in regular hair shampoo, hand soap, etc. But there are no regulations for this substance in dog shampoo. 

In our test, we also found the allergenic substance methylisothiazolinone, or MI, which is only allowed in small amounts in hair shampoo. In dog shampoo, there are no specific concentration limit for  MI. We don't know the concentration of MI in dog shampoos, but we generally recommend avoiding it if you want to reduce your risk of developing contact allergies. 

There is also no requirement for a full ingredient list of all chemicals on the packaging, as there is for personal care products. Fortunately, you can still find a full ingredient list on several dog shampoos in the test. 

"A lot of manufacturers of dog shampoo do provide information on all the ingredients, even though they're not required to. We highly support this, as it's important to know what you're washing your dog with and what you're coming into contact with yourself while doing it," says Stine Müller, Test Manager at The Danish Consumer Council THINK Chemicals. 

Since there's no requirement for a full ingredient list on dog shampoos, they cannot be found in our app, Kemiluppen. 

Be Aware of Marketing  

It's easy to fall for claims that make a dog shampoo sound like a better, milder, and more natural product. But the claims don't always tell the whole truth. 

Here are examples of dog shampoos with potentially misleading marketing: 

  • A dog shampoo from Greenfields is described as "sensitive," but it contains isothiazolinones that can cause allergy.  
  • A dog shampoo from Trixie is described as "mild," but it also contains isothiazolinones. 
  • A dog shampoo from Pet Head says it's "nasties-free," but contains BHA, which is suspected of being hormone-disrupting. It also mentions "natural oils and extracts," which is true, but it's important to remember that perfume  from natural oils are just as allergenic as synthetic perfuming substances.  
  • A dog shampoo from Bugalus is described as "paraben-free." Parabens are a group of suspected endocrine-disrupting substances. It's true that there are no  parabens in it, but the shampoo contains another suspected endocrine-disrupting substance in the form of a UV filter, benzophenone-4. 

 If you'd like a dog shampoo with specific ingredient requirements, you can instead look for the Nordic Swan Ecolabel- and  allergy labels, which are also found on some dog shampoos. 

These Dog Shampoos Are Free from Unwanted Chemicals  

Are you looking for a dog shampoo without perfume, allergenic substances, or suspected endocrine-disrupting substances? Then there are seven dog shampoos in the test that are free from a variety of unwanted chemicals and receive an A-rating in the test. These are: 

  • B&B Groomer’s Organic Shampoo 
  • Danavet Shampoo 
  • Ingredipet Moisturizing Shampoo 
  • Kovaline Fur Shampoo 
  • KW Oat & Aloe Vera Shampoo 
  • Lila Loves It Shampoo Sensitive 
  • Nathalie Deluxe Shampoo 

Four Tips for Dog Shampoo 

  •  Consider whether it's necessary to wash your dog with dog shampoo and how often it is required.  
  • Try to avoid allergenic substances in dog shampoo, such as perfume or isothiazolinones. You can choose from the seven dog shampoos that get an A-rating in the test.  
  • Look for the Nordic Swan label or allergy labels like Asthma Allergy Nordic or AllergyCertified.  
  • Apply dog shampoo to a smaller area first to see if you and your dog can tolerate the product.

About the test

  • Our test is a declaration test, where we identify the ingredients in the products either from the packaging, company websites, or by contacting the companies behind the products. 

    We have reviewed the ingredient list for chemicals that may be allergenic, environmentally harmful, endocrine-disrupting, etc. 

    • 7 dog shampoos are free from a range of unwanted chemicals and receive the best rating, the A-rating. 
    • 9 dog shampoos contain perfume that can cause allergyand receive a medium rating, the B-rating. 
    • 11 dog shampoos contain suspected endocrine-disrupting substances or allergenic substances and receive the worst rating, the C-rating. 
    • For 2 dog shampoos, we were unable to obtain information on the ingredients, so we don't know what's in them. They also get the C-rating. 
    • 5 dog shampoos contain isothiazolinones, which are preservatives. These include methylchloroisothiazolinone, methylisothiazolinone, and benzisothiazolinone. These substances are allergenic and problematic for the environment. 
    • 2 dog shampoos contain substances suspected of being endocrine-disrupting in the form of BHA and benzophenone-4. 
    • 1 dog shampoo contains sodium salicylate, suspected of harming the fertility. 
    • 1 dog shampoo contains iodopropynyl butylcarbamate, an allergenic preservative. 
    • 3 dog shampoos contain formaldehyde-releasing preservatives, which can cause allergy, in the form of DMDM hydantoin or benzylhemiformal. 
    • 13 dog shampoos contain perfume. 7 of these contain one or more of the allergenic fragrances that has to be declared, such as limonene, citronellol, hexyl cinnamal, and linalool. The rest are just labeled "perfume." These substances can cause allergies. 
    • 8 dog shampoos contain various plant extracts that can cause allergy. 
    • 3 dog shampoos contain various EDTA compounds, which are problematic for the environment.