Hyperthyroidism was first documented in cats in the late 1970s. But in the ensuing decades, the number of cats diagnosed with the disease has increased steadily. Whether this is because of greater awareness about feline hyperthyroidism — and therefore, more diagnoses — or because the incidence of the disease has increased, hasn’t been fully determined. But many vets suspect that there actually are more cases than there were 30 years ago.
There have been many theories about why hyperthyroidism is on the rise, including environmental toxins and immune stressors. But researchers at the University of Illinois at Urbana-Champaign have recently found what they see as a connection between polybrominated diphenyl ethers (PBDEs), flame-retardant chemicals commonly used in furniture and electronics, and feline hyperthyroidism.
The scientific community has been warning of the dangers of PBDEs for more than six years now, noting that PBDE levels in children in the US, Norway, Australia, and the Faroe Islands are higher than those of adults. The chemicals have been proven to impair nervous system development and disrupt hormone function — particularly estrogen and thyroid hormones — in humans. Although a 2007 study suggested the connection between PBDEs and hyperthyroidism, there had been no conclusive evidence of a connection until recently.
The study “The Feline Thyroid Gland: A Model for Endocrine Disruption by Polybrominated Diphenyl Ethers (PBDEs)?“, released in February 2012, seems to make a good case. Researchers studied 62 client-owned and 10 feral cats and found that the level of PBDEs in the indoor cats was significantly higher than that of the ferals. The main source of PBDE contamination, according to the study, was household dust. The hyperthyroid house cats (41 of the 62) lived in houses where the PBDE concentrations were significantly higher than those of the house cats with normal thyroid levels (21 of the 62).
But how do PBDEs get into our home environments?
Mostly through the use of furniture treated with the chemicals, which are commonly used as flame retardants.
And who spends a lot of time lounging on furniture and hanging out close to the carpets, where PBDE-laced dust can accumulate?
So what do we do? Very few of us can afford to just run out and spend thousands of dollars on new flooring and furniture. The abstract of the study doesn’t seem to indicate that the scientists offered any suggestions.
Because PBDEs have been heavily regulated, I imagine that newer furniture and carpeting is less likely to contain the chemicals. I’d suggest that when the time comes for you to replace yours, you research what flame retardants were used and be sure to avoid anything treated with PBDEs.
I believe that our chemical-laden world has produced bizarre cocktails of toxins that, individually, may have been deemed as safe — but when brought together, maybe they create new compounds that are more dangerous than manufacturers, regulators, and scientists might have imagined.
I know that some chemical exposure is unavoidable, but I can do my best to minimize the risk by using household cleaners and laundry products with few to no chemicals and purchasing cat food and treats that are as preservative-free as possible. It may not stop the onset of disease, but I hope that by doing these things I can keep the risk relatively low.
How about you? Do you have any suggestions for keeping your cats’ chemical exposure to a minimum?