Elevated PBDE levels in pet cats: sentinels for humans?

Area of Science:

• Environmental Science
• Toxicology
• Veterinary Medicine

Background:

• Feline hyperthyroidism (FH) incidence has risen alongside the use of polybrominated diphenyl ethers (PBDEs) in household products.
• Indoor living and canned food consumption are linked to FH risk, suggesting environmental exposure pathways.

Purpose of the Study:

• To investigate the association between PBDE body burdens and feline hyperthyroidism (FH).
• To compare PBDE levels in hyperthyroid (HT) cats with healthy and sick non-HT cats.
• To explore PBDE exposure routes in pet cats, including diet and house dust ingestion.

Main Methods:

• Serum samples and clinical data were collected from 23 cats (young, old non-HT, and HT).
• PBDE congeners in serum and cat food were quantified using gas chromatography-mass spectrometry.
• Serum PBDE concentrations and congener ratios were analyzed in relation to health status and age.

Main Results:

• PBDEs, particularly BDE-47, 99, 207, and 209, were detected in all cat serum samples.
• No significant difference in cumulative PBDE serum concentrations was found between HT and non-HT cats due to high variability.
• Lower BDE-47/99 and 100/99 ratios in HT cats suggest age- or disease-dependent alterations in PBDE metabolism.

Conclusions:

• Cats exhibit significantly higher PBDE body burdens compared to U.S. adults, indicating substantial environmental exposure.
• While a direct correlation between PBDE levels and FH was not established, altered PBDE metabolism in HT cats warrants further investigation.
• Pet cats can serve as valuable sentinels for assessing human exposure to PBDEs and potential adverse health effects.