Possible Connection Between Household Pollutant and Feline Hyperthyroidism

The ASPCA® (The American Society for the Prevention of Cruelty to Animals®) has recently learned about a new study conducted by the Environmental Protection Agency (EPA) that investigated the possible connection between the presence of polybrominated diphenyl ethers (PBDE)-a flame retardant chemical added to a wide variety of household products-and an increase in feline hyperthyroidism. The study-lead by Dr. Janice A. Dye and published in the journal Environmental Science and Technology on August 15, 2007-confirmed high levels of PBDEs in some housecats; however there was not conclusive evidence linking this to the disorder.

The use of PBDEs has been under scrutiny for several years as a potential health risk for humans, potentially causing problems in both the nervous and reproductive systems. The recent attention towards its effects on cats is fueled in part by concern regarding what these findings may indicate about potential problems affecting humans in the long run.

"As indoor housecats spend a large portion of their lives inhabiting the same environment as their owners, it is definitely concerning to find the presence of PBDEs in our pets," says Dr. Louise Murray, Director of Medicine for the ASPCA's Bergh Memorial Animal Hospital, and who is a board-certified internist. "It also underlines the fact that, as always, pet owners need to be aware of the possible risks found inside the home and the effects on their pets' health."

In an effort to help pet owners understand the complexities of this information, the ASPCA offers a few answers to common questions about PBDEs:

What are PBDEs?

PBDE (polybrominated diphenyl ethers) is a common flame retardant used in the production and manufacturing of a wide variety of household items, most notably, upholstery, carpets, and mattresses. In use since the 1970s, products that contain PBDEs have been found to shed this chemical into house dust, which can then be inhaled or ingested into the body.

Why should I be concerned about PBDEs?

PBDEs have been linked to a number of studies in regard to human health care and have been hypothesized to affect both the nervous and reproductive systems. Current research in veterinary medicine is analyzing the presence of PBDEs and deteriorating illnesses in companion animals.

What is feline hyperthyroidism?

"Hyperthyroidism is one of the most common conditions found in older cats," says Dr. Murray. "It's usually caused by a benign tumor of one or both thyroid glands, which can lead to increased levels of thyroid hormone in the body." Symptoms of hyperthyroidism in cats can include weight loss, rapid heart rate, vomiting, diarrhea, increased appetite and/or thirst and increased urination.

Is feline hyperthyroidism fatal?

Dr. Murray clarifies that feline hyperthyroidism, when treated with the appropriate therapy, is not a fatal disease. "This is generally an extremely treatable disease, and with certain treatment methods, can even be cured," she says. "The disease is mainly fatal in cats who have not received timely care, resulting in heart disease and eventually heart failure."

Do PBDEs cause feline hyperthyroidism?

"Although it is possible that PBDEs may increase the risk of hyperthyroidism in cats, this disease is a common illness in senior cats," says Dr. Murray. "Due to better health care now available to our pets, and the benefits of living inside the home, cats are living longer, and as a result the increase in cases of thyroid disease is not unexpected."

Is feline hyperthyroidism becoming an epidemic?

As our nation continues to modernize and improve its health care (for both humans and their pets) the growing population of the elderly has brought with it an increase in some diseases. Therefore, Dr. Murray says, "it is difficult to ascertain whether certain illnesses, such as feline hyperthyroidism, are a direct result of PBDEs and not simply a result of an aging population."

How can I keep my pet safe from such potential PBDE dangers?

To keep you and your pet safe, the ASPCA recommends taking the following precautions:

• Use a vacuum with a HEPA filter and change the filter regularly.
• Use an air conditioner with HEPA filter and change the filter regularly.
• Cover tears in upholstery that expose polyurethane foam, particularly if the foam is crumbling.
• Cover mattresses with tightly woven allergen barriers to reduce dust that could carry PBDEs.
• Do not remove the mattress label, as it will tell if polyurethane foam was used.**

About the ASPCA®

Founded in 1866, the ASPCA® (The American Society for the Prevention of Cruelty to Animals®) was the first humane organization established in the Americas, and today has one million supporters. A 501 [c] [3] not-for-profit corporation, the ASPCA's mission is to provide effective means for the prevention of cruelty to animals throughout the United States. The ASPCA provides local and national leadership in animal-assisted therapy, animal behavior, animal poison control, anti-cruelty, humane education, legislative services, and shelter outreach. The New York City headquarters houses a full-service, accredited animal hospital, adoption center, and mobile clinic outreach program. The Humane Law Enforcement department enforces New York's animal cruelty laws and is featured on the reality television series "Animal Precinct" on Animal Planet. For more information, please visit www.aspca.org.