How can we prevent another beloved pet from licking antifreeze off the ground?

Dear Car Talk

Dear Car Talk | Aug 01, 1997

Dear Tom and Ray:

We recently lost a dear cat-friend, and believe he died after consuming some antifreeze that had dripped in our driveway. We are not negligent pet or car owners -- the darned thing had never leaked before. We are terribly saddened by this senseless loss of life. Isn't there something the antifreeze manufacturers could add to the antifreeze to make it taste bad to pets? Is there something we could add to the radiator ourselves that would make the stuff taste bad, but not damage the car? An answer to this question would be a great memorial to our little friend, and hopefully prevent further poisoning accidents. Thanks.

-- Stephanie

TOM: Gee, Stephanie, I'm sorry to hear that such a horrible thing happened to such an innocent, little animal. It's too bad lawyers don't like the taste of that stuff.

RAY: You're right that pets and antifreeze don't mix, Stephanie. Antifreeze has a sweet aroma and taste, which dogs find particularly appealing. But thirsty cats go for it sometimes, too. As little as half a teaspoon of the stuff can kill an average-sized cat, and eight ounces will do in a 75-pound dog. Unless you catch it early, it shuts down the pets' kidneys within a few days, and after that, there's really nothing you can do.

TOM: And there's no substance, at least none that we know of, that you can add to antifreeze to make it less appealing to animals. There is, however, a safer antifreeze you can use. The toxic component of antifreeze is ethylene glycol. But some companies now offer antifreeze made with propylene glycol, which is only about a third as toxic as ethylene glycol.

RAY: That doesn't make it safe -- you don't want to use it as gravy on Fluffy's Friskies, but a dog or cat could, theoretically, ingest three times as much propylene glycol by accident before it proved fatal.

TOM: In terms of automotive performance, propylene glycol is almost identical to ethylene glycol. And unless you live in the Sahara or Antarctica, your car
should never know the difference.

RAY: Propylene glycol is sold under the brand names Sierra, Prestone Low Tox and Texaco PG. There may be others as well. It's a little more expensive than regular coolant, but pet owners may find the price a small one to pay.


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