Certain dog toys contain chemicals that studies suggest could lead to health problems in your dog, according to a presentation this week at the Society of

Environmental Toxicology and Chemistry conference held in California.

The worst offenders appear to be plastic fetching batons, called "bumpers," which are used to teach dogs how to retrieve.

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"In the process of training a lab, you do a

lot of work with these plastic bumpers," co-author Phil Smith was quoted as saying in a press release. "I have

a lot of bumpers in my garage, and they spend a lot of time in the

mouths of my retrievers. Well, lots of attention has been given to

chemicals in plastics lately regarding their effects on humans. Since we

all care about our dogs, and we want them to be as

healthy and smart and well-behaved as possible, we decided to look into


Smith, who raises and trains Labrador retrievers, and hunts with them as well, is an associate professor of

terrestrial ecotoxicology

at The Institute of Environmental and Human Health at Texas Tech University. He worked on the study with colleague Kimberly Wooten.

Smith and Wooten suspected that bumpers, and other dog toys, could

leach phthalates and bisphenol A (BPA) into the mouths and bodies of dogs. The chemicals are used to give

elasticity to plastic and

vinyl and are known endocrine disruptors that mimic estrogen or act as

anti-androgens. Studies indicate they could lead to negative health effects.

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To test for the chemicals, the researchers created

simulated dog saliva, then simulated chewing by squeezing purchased bumpers

and dog toys with stainless steel salad tongs. Some bumpers and toys were also weathered outside to determine if older toys gave off more chemicals.

"We found that the aging or weathering the toys

increased concentrations of BPA and phthalates," Smith said. "The toys

had lower concentrations of phthalates than the bumpers, so that’s good

news. But they also had some other chemicals

that mimicked estrogen. We need to find out what those are."

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Wooten explained that BPA and phthalates can have effects on

developing fetuses and can have a lifelong effect on offspring of lab

animals. Studies on humans have resulted in mixed conclusions, but concern was enough to warrant the U.S. government banning the use of BPA in baby

bottles this year.

Questions still remain about how much of these chemicals actually leach into a dog's mouth during play.

"The interaction of pet health and environmental

chemicals is understudied," Wooten said. "What may be a safe dose for

one species isn't always a good measure for another species. But the

amount of BPA and phthalates we found from the bumpers

would be considered on the high end of what you might find in

children's toys."

(Image: iStockPhoto)