By Rebecca Simmons

In August 2005, a beloved pet dog in Ketchikan, Alaska, died after consuming spilled antifreeze. The same month, in Bryan-College Station, Texas, 12 dogs within five blocks of one another died after ingesting antifreeze.

In January 2006, a Canadian woman found her cat staggering and unable to stand. The concerned guardian rushed the animal to the veterinarian, but it was too late—the cat died soon after, as a result of antifreeze poisoning.

Because it only takes a few tablespoons of highly toxic antifreeze to seriously jeopardize an animal's life, pet guardians need to know how to help keep the dangerous toxin in antifreeze away from animals, as well as detect the early symptoms of antifreeze poisoning.

"A large number of animals that ingest antifreeze do not recover. By some estimates, 10,000 companion animals die each year from antifreeze poisoning, making the toxin ethylene glycol a serious concern for pet guardians," said Stephanie Shain, director of outreach for the Companion Animals section of The HSUS.

Help Prevent Antifreeze Poisoning in Animals

1. Switch to a brand of antifreeze that contains propylene glycol instead of ethylene glycol.  2. Keep antifreeze sealed and away from animals; clean up spills completely, and fix any leaks immediately. 3. Don't allow your pet to wander unattended near driveways, roads, garages, or other places where she could come into contact with antifreeze. 4. Keep other products that contain ethylene glycol—like paint, cosmetics and novelty snow globes—out of the reach of animals, as well as any product of which you are not certain of the ingredients. 5. Monitor your pet for strange behavior. If you think she may have ingested antifreeze, take her to a veterinarian immediately.

Poison Prevention

Ethylene glycol, the main ingredient in almost all major antifreeze brands, has an inviting aroma, a sweet flavor—and a deadly aftertaste. Its appealing smell and taste often tempt animals and children to drink the highly poisonous substance.

Luckily, an alternative exists. To lower the risk to animals, consumers can switch to a brand of antifreeze containing propylene glycol, a chemical ingredient that is less toxic than ethylene glycol.

In addition to being safer, propylene glycol has a bitter taste that makes it less attractive to curious animals.

Although it's safer than ethylene glycol antifreeze, propylene glycol antifreeze is still toxic. To reduce the risk of poisoning, all brands of antifreeze should be handled carefully and treated as a highly poisonous substance.

"You should always take care to ensure that antifreeze is stored well away from animals and children, antifreeze spills are completely cleaned up, and leaks are immediately repaired," said Shain.

Pet guardians can help save their own pet from an encounter with antifreeze by closely watching the animal in areas where antifreeze may be accessible, such as roads, driveways, or garages.

Animals who are unlucky enough to stumble upon a leak, spill, or open container of antifreeze face an uphill battle to recovery. Whether it's a beloved pet, the neighbor's cat, or a wild animal, antifreeze can be deadly.

Race against Time

For pets exposed to antifreeze, the first few hours are critical. Animals who receive immediate veterinary care can recover successfully—but the longer they remain untreated, the less likely they are to survive.

"If antifreeze poisoning is suspected, pet guardians should immediately take their pet to their regular vet or to an emergency vet," said Shain.

Recognizing antifreeze poisoning symptoms is important, because many pet guardians may not immediately realize that their pet has been exposed to the toxin until it's too late.

Antifreeze poisoning occurs in two phases. In the first phase, the animal typically appears lethargic, disorientated, uncoordinated and groggy. Symptoms usually appear thirty minutes to one hour after ingestion and can last for several hours.

The second phase, which can last up to three days, is characterized by symptoms such as vomiting, oral and gastric ulcers, kidney failure, coma and death.

Thousands of pets have suffered this preventable fate, prompting several states, and the federal government, to consider legislation that could drastically lower the incidence of antifreeze poisonings in both humans and animals.

Smart Solutions

Over the last 15 years, five states—Oregon, California, New Mexico, Arizona and Maine—have successfully passed legislation requiring that a bittering agent be added to ethylene glycol antifreeze to make it unpalatable for animals and children. While other states have considered similar laws, potential costs to the industry and other legislative priorities may have both played a role in pushing the issue to the back burner and preventing passage of the legislation.

Until a federal antifreeze bittering bill becomes law, it's up to concerned citizens and animal lovers to keep even the most curious critters out from under antifreeze's sweet—but deadly—spell.

Rebecca Simmons is the outreach communications coordinator for the Companion Animals section of The HSUS.

Updated Jan. 23, 2008.