As the time nears for spring cleaning and companies offer more environmentally friendly alternatives to toxic cleaners, veterinarians say pet owners should keep in mind the potential danger to animals, which can include death.

"People expose their animals without even realizing the risk," said Dr. Karl Jandrey, who works in the emergency and critical care units at the Veterinary Medical Teaching Hospital at the University of California, Davis. "That's the most common thing that happens when you come to our emergency room - the clients put their pets at risk because they were unaware of how significant the damage could be."

Most household cleaners are safe if used as directed on labels, but pet owners who make their own cleansers using natural ingredients don't have the warnings or instructions that come with commercial products.

Cats, for example, can get stomachaches from essential oils added for orange, lemon or peppermint scents in cleaners, said Dr. Camille DeClementi, a senior toxicologist at the Animal Poison Control Center run by the American Society for the Prevention of Cruelty to Animals in Urbana, Ill.

Most commercial green products are safe for animals, DeClementi said, but owners should still exercise the same precautions as with chemical alternatives, such as keeping pets away from an area being cleaned, not using sprays directly on a pet and making sure that dogs don't chew on the products.

If a product says "Keep out of reach of children," keep it away from pets too, DeClementi said.

The "green" label on products can be misleading because it still can be dangerous, Jandrey added. "Some still have their own toxicities. In general, they probably are a little less toxic, but not free of toxic potential. They just have a need for a larger dose to cause the same kind of symptoms," he said.

He cited antifreeze as an example. The pet-friendly version of antifreeze, propylene glycol, is "still an antifreeze product. It's still intoxicating to patients, our dogs and cats. It's just not as intoxicating as ethylene glycol."

Labels can't always account for every reaction, Jandrey said. "Each intoxicating product has different concentrations and each dog or cat, each species, has a different sensitivity to that product. So what might be intoxicating to a dog is really, really intoxicating to a cat because cats might be more sensitive," he said.

Nancy Guberti, a New York City nutritionist and healthy lifestyle coach, said some products will say green when they are not. " 'Natural' means nothing. The consumer has to be educated. It's all about awareness," she said.

Extra care also should be taken when cleaning around a pet's area, such as its toys or bedding, the experts say. Don't use fabric softener sheets that contain cationic detergents because they will give your pet - especially cats - stomach distress, DeClementi said, referring to a type of chemical soap that kills bacteria.

Such detergents and soaps, normally associated with helping to get clothes clean and fresh-smelling, can have chemicals that can sicken humans and pets alike.