Is Silica Gel Toxic To Cats? What If Your Kitty Eats It?

Silica Gel is a common ingredient used in kitty litter due to it's ability to adsorb water from the cat's urine without leaving a mess.

It is sometimes just clear but often it comes with a mixture of clear silica gel pellets as well as blue or orange pellets that change color when they get wet.

But some cat owns may worry about their cat eating some of these pellets or maybe you've seen your cat eat some and you want to know is silica gel toxic to cats?

Clear silica gel pellets are non-toxic for cats to touch and consume. They are basically synthetic sand with microscopic pores for catching water. However, colored silica gel crystals are coated with chemicals that are expected to be carcinogens and may be harmful to your cat if consumed in large quantities.

While I don't personally own a cat I do have friends who have cats which I always love seeing and playing with.

I have recently been doing research into whether or not silica gel is safe to touch and I wanted to help cat owners out there learn for themselves about whether or not silica gel is toxic to your cats and if you should seek an alternative kitty litter.

Clear Silica Gel Is Non-Toxic To Cats


White/clear silica gel is a form of silicon dioxide, Si02. This occurs in nature as sand.

The difference between sand and silica gel is that silica gel is non-crystalline and highly porous whereas sand is crystalline and non-porous.

These pores or tiny microscopic cavities are what allow silica gel to adsorb water.

The silica gel crystals are not choking hazards and they are not absorbed by the body but rather passed through the stool.

Eating small amounts of silica gel or sand is unlikely to cause any major health issues but regularly eating large amounts of it could potentially lead to gastric pain, vomiting, diarrhoea or bleeding.

Silica Gel Packets Are Non-Toxic To Cats

According to ASPCA cats are more likely to eat the little silica gel packets that are packaged with food as they can retain the smell of the food item and thus be more appealing to the cat.

These little packets are often labelled with “DO NOT EAT” but this is generally due to the fact these packets are a choking hazard for children because of their size.

The silica gel crystals inside are generally the clear ones and are on-toxic.

Colored Silica Gel IS Toxic To Cats

While clear silica gel is non-toxic to cats the colored silica gel (usually blue) contains a chemical coating that IS toxic to cats and can also be toxic to humans.

Blue silica gel is generally coated with cobalt chloride and this is the color you most frequently find in kitty litters.

These crystals will change color and turn pink when exposed to water, allowing you to see when you can has weed on them.

IHC World says cobalt chloride is a possible carcinogen (cancer causing) and that it is very toxic and a skin sensitiser.

Generally this is sparsely used in kitty litter with the majority of the litter box being the clear silica gel beads while a small percentage is the blue ones.

Still it's got a carcinogenicity category of 1B which means it's presumed to have carcinogenic potential for humans. Blue kitty litter may be exposing your cat and yourself to a substance that could increase you chance of getting cancer.

If the colored silica gel is green then this is likely coated in Methyl Violet (also known as Crystal Violet). This turns orange when it comes in contact with water.

This isn't much better. It's also harmful when swallowed and is also a suspected carcinogen and may increase your risk of cancer.

What Should You Do If Your Cat Ate Silica Gel

If you're in a situation where you've just discovered that your cat has eaten silica gel, either from a small packet or from their kitty litter then STAY CALM!

I know this is easier said than done.

Given that silica gel is non-toxic it is unlikely that you need to immediately respond to the situation.

While blue silica gel is toxic it occurs in such small amounts in kitty litter that it is unlikely to pose any huge threat unless you cat has consumed a large quantity of it it.

I am NOT a vet but from the research I have done it seems most people are advised to watch their cat closely and if they notice any changes to go and see a vet.

Most likely the silica gel will pass through their stool.

There is a small chance it could cause an obstruction but this is extremely rare. If you're worried then giving your kitty some petroleum gel (like hairball gel) to move things along may help.

Adverse effects to look for are throwing up, constipation, diarrhea or bleeding. Keep a close eye on your feline friend and if you notice anything out of the ordinary then take them to see a vet.