When dogs squeeze plastic fetching batons in their slobbery mouths during training, they could be ingesting potentially dangerous chemicals, researchers say.
These batons and other toys might leach phthalates and bisphenol A (BPA), chemicals in plastics that have been linked to some harmful human health impacts, finds a new study.
"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 this," Phil Smith, an associate professor of terrestrial ecotoxicology at Texas Tech, said in a statement.
For the study, Smith and Kimberly Wooten, a graduate student, made artificial dog saliva, then squeezed fetching batons and dog toys with stainless steel salad tongs to simulate chewing. They also weathered some of the bumpers and toys to test if that would eke out 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."
Both phthalates, which are used to make materials more flexible, and BPA are suspected to have adverse hormonal effects in humans when they break free of plastics and get into the body. Loose BPA, for example, could migrate out of a plastic microwaveable container into food that we eat. In the body, BPA masquerades as a sex hormone, which could mess with normal development (depending on the amount of exposure) and have serious implications for infants and children. [5 Ways to Reduce Toxins in Your Home]
Among some recent findings, scientists have said exposure to BPA could worsen female fertility problems and boost the risk of artery narrowing. Exposure to the chemical in the womb also could contribute to behavioral problems and obesity later in life, studies have suggested.
People are generally not exposed to BPA at the level that the U.S. government finds to be dangerous. Nonetheless, the Food and Drug Administration (FDA) recently banned the chemical from baby bottles and sippy cups.
It's not clear what influence these chemicals might have on dogs, and the researchers say more work is needed in this area.
"The interaction of pet health and environmental chemicals is understudied," Wooten said in a statement. "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."
The research has not been published in a peer-reviewed scientific journal, but the results were presented at the Society of Environmental Toxicology and Chemistry conference held in California last month.
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