Hyperthyroidism in cats was so rare a few decades ago that it didn’t even have a name. Now, cats are being diagnosed at an alarming rate and the direct cause is still uncertain.
That’s why Campus Veterinary Clinic is teaming up with the California Environmental Protection Agency to conduct a study and find what exactly is causing hyperthyroidism in cats. But we need your help to uncover the possible sources of exposure of household cats to chemical contaminants. If you’re interested in participating in the study, or want to learn more about feline hyperthyroidism, read on!
Q: What is hyperthyroidism?
A: Hyperthyroidism, or overactive thyroid, is a multi-system disorder related to an increase in thyroid hormones. Symptoms include weight loss, increased appetite, thirst and urination, increased rate of metabolism, periods of vomiting or diarrhea, hair loss and irritability.
Q: Why did hyperthyroidism cases spike in cats?
A: Cases of feline hyperthyroidism began to emerge at the same time as flame retardant foam appeared in furniture.
Q: How are flame retardant materials affecting cats?
A: Common flame retardants include Polybrominated Diphenyl Ethers (PBDEs) and chlorinated Tris (TDCPP). 
California’s furniture flammability standard led to the use of these flame retardants in furniture foam, and as a result, Californians and California house cats have the highest PBDE serum levels in the nation. Household dust contains these flame retardants, and with cats’ grooming habits, the intake of these flame retardants is very high.
Q: What about other animals?
A: Cats, as a species, have the highest flame retardant levels. The average PBDE level in cats is 5 times higher than dogs, and almost 10 times higher than people.
The Environmental Chemistry Laboratory is collaborating with local veterinarians and radiologists to explore the presence of certain chemical contaminants (such as the PCBs, pesticides and flame retardants) in cats’ blood and in their environment: house dust and cat food. The study will better uncover the possible sources of exposure of household pets to chemical contaminants, and provide information on the potential role of such chemical contaminants in the development of hyperthyroidism in cats.
If you would like to assist us in this research study, we will need to draw one tube of blood from your cat during their visit to the clinic. Subsequently, research scientist, Ms. Weihong Guo, will be contacting you to obtain a sample of your house dust (from your vacuum cleaner bag) and some samples of your cat’s food. Please print and fill out the form below, and bring it to the clinic if you wish to participate. Call us at (510) 549-1252 if you have any additional questions!
Reprinted from the California Department of Toxic
Substance Control Feline Hyperthyroidism brochure.