The gel ice packs that most of us have in the freezer are fantastically useful. They keep your drinks or lunch cool in the cooler or lunch box and can be applied as targeted cold therapy after an injury.
They don't freeze hard like regular ice, allowing you to mold them to your body. These advantageous properties can be attributed to the strange viscous gel occupying the inside of most ice packs. But what exactly is in these gel ice packs? Is it safe?
Reusable gel ice packs typically contain mostly water. Various chemicals are added to lower the freezing temperature and blue dye is added so it's less likely to be consumed. The specific additives vary between products but are generally safe and non-toxic. Large quantities would need to be consumed for it to pose any serious danger to your health.
If you have ever had a reusable ice pack leak its blue gel onto your skin, you will certainly have wondered what weird chemicals might be in the viscous goo. Did you just poison yourself with toxic waste or is there nothing to worry about?
In this article we list the specific chemicals commonly found in gel ice packs and discuss the toxicity of each one.
What Makes Up the Gel in Ice Packs?
Back in the day, gel ice packs contained the same toxic compounds we use in antifreeze formulations (diethylene glycol and ethylene glycol).
Thankfully however, the ones you will find today contain much safer ingredients. The liquid or gel in ice packs is rarely (if ever) toxic or poisonous.
Most commonly they will contain:
- Propylene Glycol
- Hydroxyethyl Cellulose
- Sodium Polyacrylate (SAP)
- Silica Gel
Let’s take a closer look at each ingredient.
Good ol’ H2O is the main ingredient in every gel ice pack that you are likely to find. Essential to all life on earth, we can safely say that water is 100% non-toxic.
In fact, some doctors recommend drinking up to 8 glasses per day!
Gel packs will not be pure water though as pure water sets completely solid and doesn't allow the ice pack to have that moldable quality.
For this reason extra additives are put into the gel pack to give it a lower freezing temperature and a more gel-like consistency.
Propylene Glycol is a thick, colorless liquid with a slightly sweet taste. It acts as a solvent and carrier in pharmaceutical preparations and is a main component in the vape liquid for E-cigarettes.
When you consider that it freezes at -59°C/-74ºF it’s easy to understand why manufacturers commonly include this compound in order to lower the freezing temperature of the ice packs.
Propylene glycol allows the gel ice packs to get extremely cold but never freeze completely solid.
Propylene glycol is however the component to be the most worried about in the event of accidental ingestion of the ice pack gel.
It is generally recognized as safe by the US Food and Drug Administration (FDA) but toxicity can occur at extremely high doses or with prolonged use.
An overdose could result in nausea and vomiting as well as feeling disorientated or even lead to unconsciousness.
But honestly you would have to be ingesting a lot of gel packs in order to be worried about an overdose of this chemical.
Hydroxyethyl cellulose (HEC) is a water-binding thickening agent used in a wide range of products. You can find it in everything from pharmaceuticals and cosmetics to adhesives and building materials.
Being derived from cellulose, this component is non-toxic and biodegradable.
Cellulose is a fibrous polysaccharide found in the cell walls of plants and is therefore abundant in nature. Every time you eat plant matter you are consuming cellulose.
Use of cellulose could be one reason some ice packs have expiration dates. However, in reality most ice packs can be used for years and year (until they break). They just might become more rigid over time and loss their gel like consistency.
You might notice that some ice packs are filled with what seem like little squishy beads. These gel beads are made of a Super Absorbent Polymer (SAP) called sodium polyacrylate.
Super Absorbent Polymers are just that; super absorbent. Which is why you will also find these polymers used in the lining of diapers.
Fun fact: Did you know you can use the inside of (unused) diapers to make your own gel ice pack!
Dry SAP beads will swell in size as they absorb liquid and could potentially block your intestines if ingested.
However, sodium polyacrylate beads found inside ice packs will likely be fully saturated so will not swell any further. If swallowed they might cause mild irritation but are considered to be non-toxic and generally harmless.
You should not dispose of these types of gel packs down your drain. The super absorbent polymer can completely block your drain and be difficult to clear. It can also continue to absorb water and swell inside even more.
If your ice pack breaks open and gets on your skin don't worry. This product is used in baby diapers and if it is safe for their skin it should be fine for yours.
Silica gel beads are useful in ice packs because they absorb a lot of water and stay separated when frozen. This makes the pack able to be molded in place around an injured body part.
Silica gel is most commonly used as a desiccant in those little packets you find inside bottles of pills to keep them dry. These desiccant packs happen to be one of the most commonly ingested foreign objects by small children.
Fortunately though, silica gel is basically just sand. It is chemically unreactive and harmless if swallowed, despite the warnings on the packets.
Did you know that silica gel is even used in kitty litter? Silica gel is non-toxic to cats as well as being non-toxic to humans.
What To Do If You Ingest A Gel Pack
Ice packs can, and do, leak inside of coolers containing food and drinks. Take a look here to find out what to do if this happens to you.
If you or, perhaps your child, does end up ingesting some of the gel from inside the ice pack, don’t panic.
The first thing you should do is rinse your mouth out with water. Do not induce vomiting, but rather take a few sips of water to clear any irritation from your throat.
If you're extremely concerned call your local poisons hotline and they can offer you advice.
In case of contact with the eyes, rinse them with tepid water for a few minutes and if your skin is exposed, simply wash with soap and water.
Other Types of Ice Packs
There are other ice packs on the market, which contain a liquid rather than a gel. Also some people prefer to make their own ice packs at home using ingredients like salt and isopropyl alcohol. Click here to learn how to make a homemade ice pack with hand sanitizer.
To learn more about the contents and toxicity of both of these types of ice packs take a look at this article.
Modern gel ice packs are manufactured using water and a variety of refrigerant chemicals and thickeners, none of which are particularly poisonous unless consumed in very large quantities.
For your convenience here is a table of the most common ingredients and their toxicity level.
|Propylene Glycol||FDA approved but high doses can be dangerous|
|Hydroxyethyl cellulose (HEC)||Made from plant matter. Non-toxic and biodegradable|
|Sodium Polyacrylate||May cause mild irritation but otherwise non-toxic|