Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, November 13, 1994 TAG: 9411290015
SECTION: EXTRA PAGE: 7 EDITION: METRO
SOURCE: KAREN DAVIS
DATELINE: LENGTH: Medium
Ethylene glycol is the prime ingredient in traditional antifreeze products. Its sweet taste attracts animals to drink from puddles of the stuff that may have formed under cars in the driveway or on the garage floor. But the substance is deadly. As little as half a teaspoon can kill a cat, and less than two ounces can kill a dog.
``It's a suffering death,'' said Lucas, who tearfully recalled Bart's last hours. After the cat had been missing for a few days, her husband found him one morning lying by the roadside, barely alive.
``His breathing was labored. We thought he had been hit by a car,'' Lucas said.
The couple took Bart to a veterinary hospital immediately. But an examination revealed no broken bones or other trauma associated with being struck by a car. The doctor then ordered blood tests to confirm his suspicions of accidental poisoning, but for Bart, it was too late. He was already in the renal stage of antifreeze poisoning in which the kidneys start to fail.
Depending on the dose ingested, death from antifreeze poisoning can come quickly in a matter of four to five hours, or it may drag on for a couple of days. During the first 12 hours after ingestion, central-nervous-system depression sets in, said Dr. Dennis Blodgett, a toxicologist and veterinarian at the Virginia-Maryland Regional College of Veterinary Medicine.
``The animal acts tired and sleeps more than normal'' and may even stagger and appear drunk, he said. Depending on the severity of these early symptoms, the pet owner may not suspect anything is seriously wrong until it's too late. The second stage involves the heart and lungs and also is not easily recognized. About 24 hours after ingestion, the animal enters the renal stage, and once the situation has progressed this far, the chance of recovery is generally poor.
New antifreeze products on the market, such as Sierra, Sta-Clean and ECO III, use propylene glycol as the main ingredient. Propylene glycol is significantly less toxic than ethylene glycol. In fact, propylene glycol is FDA-approved for use in some foods, alcoholic beverages, cosmetics and pharmaceuticals. And because it is a carbohydrate energy source, it is also used as an additive in some soft-moist pet foods.
Although not totally without potential problems, propylene glycol is considered to be about ``three times safer, if not more,'' than ethylene glycol, said Blodgett. That means an animal that licks a small spill on the garage floor can ingest about three times more of the newer product without suffering the devastating effects of conventional antifreeze.
Still, ``it is feasible that an animal can consume enough propylene glycol to become sick,'' Blodgett said. In the early stages, its effects are similar to that of the deadlier antifreeze, with central nervous system depression and marked sleepiness. If a large enough dose is ingested, coma or death can result.
``The dose makes the poison,'' Blodgett emphasized. When ingested, propylene glycol is metabolized into lactic acids that are normal body constituents. However, in unusual amounts, the presence of these acids may lead to certain imbalances that require medical management.
But unlike ethylene glycol, the prognosis for an animal poisoned by propylene glycol is much better, Blodgett said, ``because of the lack of renal involvement'' and kidney damage.
As a further benefit, the taste of propylene glycol is said to be somewhat bitter, and therefore, less attractive to animals than the sweeter ethylene glycol.
Perhaps a drawback to human consumers is the cost: as much as $2 more per gallon than conventional antifreeze. But when you get ready to winterize your car this year, think about Bart and other animals that may suffer the same fate if more people don't switch to a safer antifreeze.
At the very least, be environmentally conscious and wipe up all antifreeze spills immediately, then thoroughly rinse the area afterward. Use a funnel when adding antifreeze to avoid spillage. And check under your car periodically to make sure no antifreeze is leaking.
Karen L. Davis is a Roanoke free-lance writer and pet owner. Her column runs twice a month. Send general-interest questions to The Pet Podium, in care of the features department, Roanoke Times & World-News, P.O. Box 2491, Roanoke, Va. 24010-2491.
by CNB