by Lori Straus

Vehicles need antifreeze: it’s mixed into winter windshield washer fluid and is used as a coolant so the engine and other parts don’t overheat and malfunction. However, antifreeze is highly toxic to animals, plants, the environment overall, and also humans. And it can leak from your engine and kill your pets. Here’s why.

What Is Antifreeze?

Engine coolant is usually ethylene glycol. Although it can be made from different chemicals, the ethylene glycol formulation is the most toxic to living organisms. Without antifreeze, though, our engines would heat up and stop working. Interestingly enough, once ethylene glycol has broken down, it’s harmless: it’s only water and carbon dioxide. But until then, it’s highly toxic.

How Do Pets Come in Contact with Antifreeze?

The usual culprit is inappropriate storage by the pet’s owner. Antifreeze is colorful and sweet and therefore looks attractive and tastes good to animals. Leaving a container out in the basement or garage can be enough to attract a curious pet.

However, antifreeze can also leak out of your vehicle. Routinely look for puddles of green, purple, or orange fluid under your car. You may also notice rust or discolouration on your vehicle’s radiator. Lastly, pay attention to the coolant signal on your dashboard.

If you notice any leakage, call your mechanic before driving your car again. Your mechanic may insist that you have your car towed to their garage, because driving it could further damage your vehicle.

How Does Antifreeze Kill Pets?

Antifreeze causes irreversible damage to the kidneys, liver, heart, lungs, and central nervous systems in animals. Unfortunately, it only takes a small amount of ethylene glycol to make your pet sick and possibly kill it if you don’t intervene immediately. A cat, for example, need only lick some off its fur to become intoxicated, and there have been reported cases of cats absorbing the poison through their skin.

If you notice a leak under your car, clean up the antifreeze puddle thoroughly. Just wiping it up may not be enough: if a sweet smell lingers afterwards, it could still attract animals, including your house pets.

How Do I Know If My Pet Has Ingested Antifreeze?

Within the first 30 minutes to 12 hours, your pet may walk drunk, drool, vomit, have seizures, be extremely thirsty, or have to pee often. The Pet Poison Helpline outlines the remaining symptoms. I didn’t include them here, because I worried they might be too upsetting to read.

But please note that your pet may not show signs during the small window you have to get help. You need to get a cat to the vet within the first three hours of ingestion, and dogs within eight to 12 hours. So, it’s possible that your pet may not show signs of intoxication before it becomes too late.

What Do I Do If I Believe My Pet Has Ingested Antifreeze?

Get your pet to your vet or the closest veterinarian hospital immediately.