Thyroid Disease Hits Cats Exposed to Fire-Retardants
Flame-retardant polybrominated diphenyl ethers (PBDE) may be behind a widespread disease of cats. Steve Mirsky reports.

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How’s your cat feeling these days? Irritable? Losing weight? Not feeling the nip? He may be one of the many American house cats with thyroid disease. For 30 years the epidemic has remained a mystery but a study published this week in the journal Environmental Science & Technology provides a connection between elevated levels of polybrominated diphenyl ethers (or PBDEs) and feline hyperthyroidism.
Cats love scratching soft things and this is precisely where the toxic PBDEs reside – as flame retardants used to protect carpeting, furniture and fabrics. The toxicologists confirm that cats with hyperthyroidism had PBDE levels three times higher than healthy cats.
Sadly, the toxins are also found in their beloved fishy food. So cats that enjoy juicy salmon niblets may be exposed to PBDE levels that are 12 times as high as in dry food.
Cats and humans are the only mammals that have big problems with hyperthyroidism, and so a sick cat might act as a sort of “canary in the coal mine” for us humans, giving the initial alert that your home may be contaminated.
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