Greenies, the nation's best-selling dog treat, has got some dog owners seeing red. The tooth-brushed shaped dog chew, designed to combat bad doggy breath and prevent periodontal disease, is marketed as “the original smart treat,” but 13 dogs have died after a Greenie got lodged in their esophagus or intestine, prompting some pet owners and vets to ask whether Greenies are such a good idea.

Mike Eastwood blames Greenies for the death of his dog Burt, who died of intestinal blockage. “I'm mad that their packaging states that the product is 100% edible, highly digestible and veterinarian approved, yet our dog died of it.” Eastwood and his wife, Jenny Reiff, have filed a $5 million lawsuit against the manufacturer in New York.

So what goes into a Greenie? The main ingredients are wheat gluten, glycerin, and cellulose fiber, all entirely edible ingredients, in theory. But the process of molding the chews into that cute toothbrush shape apparently compresses the ingredients into a treat that's so hard it can only be digested if properly chewed. And, of course, it's the hardness of the chew that helps clean the teeth.

Greenies acknowledges the problem with the following disclaimer on both its packaging and its website, “As with any edible product, monitor your dog to ensure the treat is adequately chewed. Gulping any item can be harmful or even fatal to a dog.”

But how do you convey the hazards of gulping down Greenies to your dog? I can't convince my cat not to wolf down her food every morning. If I don't dole out Zuzu's food a teaspoon at a time, she gulps it all down and barfs it back up. Getting your pet not to gulp is easier said than done.

Joe Roetheli, whose company, S & M NuTec, makes the Greenies, stands by his product, which has nearly three times the sales of its nearest competitor, Milk Bone. “Our product is safe. It is used every day by thousands of dogs, millions a week and it is basically a very safe product.” The FDA is looking into eight complaints but has no plans to launch a formal investigation into Greenies.

Maybe the FDA's too busy trying to keep track of the toxic Diamond Pet Foods tragedy. In December, the FDA ordered the Missouri-based company to recall all pet food made at its South Carolina plant after a batch contaminated with the toxic chemical aflatoxin killed 76 dogs.

The contamination was one of the stranger, and sadder, side effects of last summer's heat and drought, which created the perfect growing conditions for the fungus that produces aflatoxin on corn and other crops. From there, the toxin made its way into the dog food, with disastrous consequences.

So the contaminated food's been pulled from shelves in the U.S., but Reuters reports today that nearly two dozen dogs in Israel have died of liver failure in recent weeks after eating Nutra Nuggets, manufactured by Diamond Pet Foods. According to Reuters, “a rare public appeal went out on Wednesday to Israeli pet owners to bring their dogs to donate blood to help save more than a dozen canines poisoned by toxic American pet food.”

Our pets give us unconditional love in unlimited doses, day in, day out. It seems like the least we could do in return is give them food that won't kill them. Should the FDA pull Greenies off the market? Can a dog be convinced to chew its food? Do we bother to notify other countries when we've sold them a batch of contaminated pet food?