Degradation of Accelerated Hydrogen Peroxide

[JT Smith]

TL;DR Summary

What happens when accelerated hydrogen peroxide ages?

I started fostering kittens during the pandemic. A very useful veterinary disinfectant that I make use of is accelerated hydrogen peroxide. It is sold under the brand name "Rescue". In its concentrated form it has a shelf life of about 2 years. It's kind of expensive. Typically a dilution of a small portion of concentrate is made up for use within a shorter period of time.

What I am wondering is what happens to it as it gets older? Does it break down gracefully by simply becoming less concentrated? Or does it degrade in some other way? If it is the former, might it be possible to ascertain the concentration and adjust the dilution ratio accordingly, thereby extending the life of the product?

The ingredients are partially proprietary: https://rescuedisinfectants.com/wp-.../RescueConcentrate_IngredientDisclosure-2.pdf

 

[Tom.G]

Here is a link to the SDS (Safety data Sheet, formerly MSDS) from one supplier:
https://maunco.com/photos/custom/MSDS/Accel Hydrotherapy MSDS.pdf

Many other links turn up using a Google search of:
https://www.google.com/search?&q=msds+accelerated+hydrogen+peroxide

Cheers,
Tom

 

[JT Smith]

Yes, I've seen the MSDS for Rescue. I think Accel, which is also commonly used in animal shelters, is made by the same parent company, Virox.

It costs around $65 per gallon, which dilutes to at least 16 gallons. At that dilution it's enough to last me about 15 years. But it expires after 2 years. The logical thing is to just flush 85% of it down the drain and buy a new one every two years. But I wondered if it might be possible to extend that life in a controlled way. Am I nuts to think that? Compared to other consumables (food and litter) it's not very much. Still, I'll bet it can be stretched...

Is there a relatively easy way to determine hydrogen peroxide concentration?

 

[DrJohn]

Why buy a gallon if it will not last as long as you'd like after dilution? Buy a smaller amount so that you'd be able to use it all without having to throw any away.

If a gallon provides 16 gallons of diluted product which would last you 15 years but after only two years gets thrown away, buy one-tenth of a gallon, or one pint or 500ml. On dilution, this would still be within the recommended usable life.

So even if the price for 500ml worked out at two or three times the cost per unit volume as buying a gallon, you would not be throwing any away and save money in the long run.
And why not speak directly to a vet or care centre that uses it, explain your situation, and buy 500ml from them every two years?

I think you are approaching the problem the wrong way - really, you need to find a source of the product in a smaller container.

 

[JT Smith]

Why buy a gallon if it will not last as long as you'd like after dilution? Buy a smaller amount so that you'd be able to use it all without having to throw any away.

If a gallon provides 16 gallons of diluted product which would last you 15 years but after only two years gets thrown away, buy one-tenth of a gallon, or one pint or 500ml. On dilution, this would still be within the recommended usable life.

So even if the price for 500ml worked out at two or three times the cost per unit volume as buying a gallon, you would not be throwing any away and save money in the long run.
And why not speak directly to a vet or care centre that uses it, explain your situation, and buy 500ml from them every two years?

I think you are approaching the problem the wrong way - really, you need to find a source of the product in a smaller container.

Yes, of course, that is so obvious. And I spent time searching for a smaller volume. But AFAIK the smallest size available is 1 gallon.

 

[berkeman]

Summary: What happens when accelerated hydrogen peroxide ages?

What I am wondering is what happens to it as it gets older? Does it break down gracefully by simply becoming less concentrated? Or does it degrade in some other way? If it is the former, might it be possible to ascertain the concentration and adjust the dilution ratio accordingly, thereby extending the life of the product?

I use standard H2O2 in my EMS work and go through enough of it that I'm able to keep my stock fairly current. But my patients are a lot bigger than kittens...

In my brief Google searching on your question, it seemed like the universal advice from the manufacturers was to store it in a cool, dark place, and use it up after you first open the container. That implies to me that exposure to fresh O2 from opening the container may cause some of the degradation issues, so perhaps transfering it to a no-air flexible bag container (with similar dark/no-light-transmission characteristic like the original brown bottles) might help to extend the shelf life as you use it up. Of course the manufacturers are not going to give you that advice...

Also, it seems like one way to try out your idea of diluting the concentrated H2O2 less as it ages might be to do an experiment with fresh solutions of different concentrations on blood samples to observe how energetically they react with the samples. Then compare that against 1 y/o and 2 y/o bottles with the same dilution ratios. There are several issues that I can see with this experimental approach:

1. Judging the reaction rate of the H2O2 on the blood sample will be pretty ballpark, varying from "lots of bubbling" to "hardly affecting the sample at all". You'd need to try it a few times to see if you can come up with a good 0-10 rating scale or something.
2. I don't know of any good sources of the 10ml or so of blood that you would need for these experiments. If you live in the country and have livestock, this may not be a problem however.
3. I'm just guessing that reactivity with blood is a good estimator of the concentration and effectiveness of the H2O2 for disinfection purposes, but that's only my guess.

You might also consider some other kitten disinfecting means that has a longer shelf life limitation, or a way that you can mix the solution as needed from common products that do not have a shelf life limitation. Or find other folks who use the same type of H2O2 that you use, and split the cost of the gallon jugs between yourselves to use them up within the shelf life limitation.

Paging @jim mcnamara and @Borek and @chemisttree for their thoughts.

Good luck!

 

[tech99]

I use 100 Volume Hydrogen Peroxide in the laboratory in 5 litre bottles and it lasts several years. It last better in the concentrated form as it contains an inhibitor, and degrades quicker once diluted. The following link from thr Royal Society of Chemistry gives details of experiments to generate Oxygen using various catalysts, including potato, but be careful about metal catalysts as they can create explosion. Maybe do a test when the product is new and film the result for future reference.
https://edu.rsc.org/download?ac=12409

 

[chemisttree]

Rescue is more than just H2O2. The “activated” part of it is phosphoric acid and the concentration is sufficient to produce a pH of 1.0… likely a buffer. Acidic peroxide has a stronger oxidizing power.

You start with a peroxide concentration of 4.25% in the concentrate which isn’t too different than the stuff in the grocery store which is 3%. Of course the 3% solution at the grocery store doesn’t have phosphoric acid in it. You could always add a little bit of hydrogen peroxide from the grocery store to the dilution that you’re making with the Rescue. it wouldn’t hurt a thing. If you’re concerned that you’ve lost hydrogen peroxide power, you could add a bit of over-the-counter hydrogen peroxide, the 3% stuff, to your rescue dilution.
As far as a hydrogen peroxide test, there are test strips available to test for hydrogen peroxide concentration in varying levels. Here’s one for example…

 

[chemisttree]

Your 1:16 dilution from a 4.25% concentrate would give you about 2.7 g H2O2 per liter of dilution or 2700 ppm. Thats right in the middle of these test strips scale!

Good luck and thank you for your good work with the animals!

 

[JT Smith]

...That implies to me that exposure to fresh O2 from opening the container may cause some of the degradation issues, so perhaps transfering it to a no-air flexible bag container (with similar dark/no-light-transmission characteristic like the original brown bottles) might help to extend the shelf life as you use it up. Of course the manufacturers are not going to give you that advice...

That makes sense and would be very easy to do.

Also, it seems like one way to try out your idea of diluting the concentrated H2O2 less as it ages might be to do an experiment with fresh solutions of different concentrations on blood samples to observe how energetically they react with the samples.

This sounds like you're joking but I don't think you are. Even if it would work I do not have access to fresh blood in any quantity!

I've wondered if I could simply use my nose to get a rough sense of the strength. But it would be pretty rough at best.

You might also consider some other kitten disinfecting means that has a longer shelf life limitation...

Bleach can be used. The beauty of the Rescue disinfectant is that, in addition to being highly effective at neutralizing the pathogens that target kittens it requires no rinsing, no cleanup. Just apply and wait for it to evaporate.

 

[berkeman]

I've wondered if I could simply use my nose to get a rough sense of the strength.

OMG, when I first read that, I got a vision of you spraying some up your nose!

(then I realized what you meant, LOL)

 

[JT Smith]

Those test strips look like a great idea. Of course they also have an expiration date. :-)

I just finished up with a young mother cat and her seven kittens. They were 3 days old when I got them and about 7 weeks when they headed off for adoption. Quite a party for a while there. I used about 50ml of the concentrate cleaning up after them and they were healthy the whole time. Kittens often get diarrhea.

Maybe $65 every 2-3 years just isn't worth worrying about. I spent at least that much on litter alone in the last 7 weeks.