The toy aisle is meant to be all about fun, but recalls, toxic imports and a dearth of regulations have left dog owners facing tough choices. Many toys are made of plastic and may contain chemicals that interfere with hormones.
A new study by researchers at the Institute of Environmental and Human Health at Texas Tech University shows that BPA and phthalates, chemicals that disrupt hormones, “readily leach” from plastic or vinyl bumper toys used to train retrievers.
Philip Smith, a toxicologist and co-author of the as-yet unpublished study, uses plastic bumpers to train his Labrador Retrievers, Bindi, age 11, and Huck, age 5. He wondered if the bumpers might expose them to hazardous chemicals.
In fact, the compounds are hard to avoid. BPA, the building block of polycarbonate plastic, is found in most food and drink cans; phthalates are common in food packaging, personal care items and vinyl plastics.
“BPA and phthalates come from many, many sources” besides pet toys, Smith says. So a dog’s “cumulative exposure may be significant.”
The study, conducted by graduate student, Kim Wooten, is one of the first to examine these chemicals in pet toys. In children’s toys, some phthalates have been banned in the U.S. and the European Union. In July 2012, the U.S. Food and Drug Administration banned BPA in baby bottles and children’s drinking cups.
Although their health effects in dogs are unknown, the hormones they interfere with regulate many biological functions.
Studies done mostly with rodents have linked BPA and phthalates to impaired development of reproductive organs, decreased fertility, diabetes and obesity, cancers, and behavioral and attention problems.
No, dogs are not mice. There are “species sensitivity differences” in regard to toxics, Smith says. For example, dogs are at greater risk than humans from eating chocolate. But while their sensitivity to synthetic chemicals may also differ, “we are unaware of specific reasons why they might respond in a significantly different manner.”
Available data suggests that the most vulnerable pets may be pregnant females “and perhaps young animals like puppies.”
According to a 2012 pet health report by Banfield Pet Hospital, some cancers and other diseases in dogs are increasing. “The rate of overweight and obese pets has reached epidemic levels in the U.S., affecting approximately one in five dogs and cats.”
The causes are unknown, but Smith says it’s possible that endocrine-disrupting chemicals, including phthalates and BPA, play a role.
Certain aspects of canine cancer suggest that dogs are sensitive to them, he says. For instance, exposure to estrogens raises the risk for mammary cancers. For metabolic disorders such as obesity and diabetes, researchers are finding that some hormone-disrupting chemicals appear to “affect metabolic endpoints, in addition to reproduction and behavior.”
For the toy study, the researchers tested orange and white bumpers from two unidentified makers, using artificial saliva to simulate a dog chewing a bumper. The amount of toxics released in a dog’s mouth couldn’t be determined due to the use of simulated saliva,
But what is a high exposure in dogs?
“We are not aware of any exposure guidelines pertaining to these particular chemicals and dogs,” Smith says.
They suspect the levels released from the bumpers would be very high, though, compared with children’s toys.
The study also examined BPA and phthalates from ordinary plastic pet toys sold in stores. The bumpers leached more, but the results suggest that the other toys might have released other hormonally-active chemicals.
Smith highlights the uncertainty that shoppers face, saying the bumpers might have been made from different materials, or perhaps the packaging limited the release of some chemicals before the experiment.
Or, the less affected toys may have involved “materials that are also used in the manufacture of children’s toys.”
“We’re not really sure, but intend to pursue the question further.”
Good thing for pet owners.
“Given the extent of plastics in the human-canine environment,” Smith says, avoiding the chemicals entirely may not be possible.
But not all plastics are the same. When it comes to leaching of chemicals “each type is very different.”
“That is why studies on individual products are important.” Pet owners need the information “to make thoughtful decisions.”
Some pet toy makers say they use BPA-free plastics.
But owners may wonder why it’s even a question. Why should they have to worry about chemicals in toys or migrating from cans, even into “organic” food, to add to their dog’s exposure?
At least—at last—it is being studied.
Smith’s team plans to continue studying the exposure of pets to chemicals. “We think there is a great deal to be learned about potential pet and human health impacts from chemicals in the environment,” he says.
And as they learn, Smith says they hope to yield the data needed “to inform decisions about how we manufacture pet products, which ones we buy, and what we allow our pets to chew.”