Is Sodium Hydroxymethylglycinate a Natural Preservative?

August 05, 2017

Is Sodium Hydroxymethylglycinate a Natural Preservative?

We've recently saw a dog shampoo that had "natural preservative" listed under ingredients.

This same product claimed this preservative was "gentle and based on the natural amino acid glycine".  

Following that clue we can presume the preservative is the bottle is sodium hydroxymethylglycinate

Why Are Some Manufacturers Using Sodium Hydroxymethylglycinate?

Pet parents, having made the links between paraben preservatives and endocrine disease and formaldehyde based preservatives and cancer risk are beginning to demand safer preservatives in products that go on dogs.

In response, parabens and the traditional formaldehyde releasing compounds like diazolidinyl urea, imidazolidinyl urea, quaternium-15, and DMDM hydantoin (often written as DMDH hydantoin) are being replaced.

Enter a preservative you may not have heard of: Sodium Hydroxymethylglycinate (also called Sodium HMG).

As opposed to the above formaldehyde releasing compounds that slowly release formaldehyde over time, sodium hydroxymethylglycinate only releases small amounts of formaldehyde under certain conditions.

Certain conditions? Well, yes.
Changes in pH and high temperatures can cause the release of small amounts of formaldehyde.  
Don't think this can happen? It can. This was posted on the Facebook page of a dog shampoo company (not ours): 
Extreme heat can cause bad ingredients to break down resulting in a release of formaldehyde


Some facts about sodium hydroxymethylglycinate:

  • The European Union has permitted sodium hydroxymethylglycinate at concentrations up to 0.5% in human products.
  • It is a very effective preservative.
  • It is based on the naturally occurring amino acid glycine. [Based on is sort of like saying a movie is based on a book. You go to see the movie after having read the book and discover the movie is NOTHING like the book! You feel jilted - as you should!]
  • From the starting base of glycine, sodium hydroxide in water is mixed with formaldehyde - going through synthetic reactions before it is sodium hydroxymethylglycinate. Since it goes through synthetic reactions, it is a synthetic compound.
  • Even at concentrations less than 1% it has been shown to cause skin and eye irritation as well as allergies.
  • It stinks. It is traditionally found in products that contain synthetic fragrance as they can mask the smell.
  • It is typically not used with truly natural products as it can cause discoloration with essential oils - lemongrass will be dark brown for example. 
  • It can react with proteins in truly natural products and break down - releasing formaldehyde so it is typically used in synthetic, not truly natural, products. 
  • Under certain conditions it can release formaldehyde.
  • There is not a lot of research available on this ingredient.
  • Dogs who are sensitive to formaldehyde will be sensitive to this ingredient. 

While sodium hydroxymethylglycinate is "safer" than many of the formaldehyde releasing ingredients that over time release formaldehyde and it is "safer" than paraben preservatives, the lack of available research combined with the potential for formaldehyde release (albeit low), and the potential for allergies and skin / eye irritation makes this a preservative we won't be using in 4-Legger products! I guess it is just as well it is not approved for use in USDA certified organic products! 




Leave a comment


Also in Fetch the 4-Legger Blog

Why you need to use safe and non-toxic alternatives to flea and tick treatments
Look to see if Your Community Hosts Free Household Hazardous Waste Drop Off Days

April 21, 2018

You may be shocked to see what is on the list for household hazardous waste. Something so toxic it has to be disposed of safely... ready to find out what it is! 

Also, check to see if there is a household hazardous waste day in your community so you can safely dispose of hazardous household waste. 

 

Continue Reading

The World's First Safe & Non-Toxic Aloe Based USDA Organic Dog Shampoo
The World's First Safe & Non-Toxic Aloe Based USDA Organic Dog Shampoo

April 14, 2018

4-Legger continues to lead the market with a new product line of USDA Certified Organic Dog Shampoo. The first aloe based USDA certified organic dog shampoo!

Continue Reading

dog yeast infection treatment | how to treat yeast infection in dogs
A Holistic Approach to A Yeast Infection In Your Dog

April 07, 2018 1 Comment

Your dog is scratching and itching. Have you had your dog's skin checked for yeast? If not, go to your veterinarian and have them check. Grain free food and high carbohydrate food are causing yeast infections along with environmental toxins, and other factors that stress immune compromised dogs.

Learn how to combine traditional and holistic approaches to get your dog relief from yeasty skin and yeast ears!

Continue Reading