Dioxin 2007. Paper abstract bibtex
Since the introduction of brominated flame retardants (such as the PBDEs), increases in feline hyperthyroidism have been observed. We hypothesized that PBDE exposure was linked to the increased occurrence of hyperthyroidism in cats. Herein, PBDEs in serum of pet cats and levels in cat food were determined. Samples were extracted and analyzed by electron capture negative ionization gas chromatographic mass spectrometry for major PBDE congeners. Data indicated that cats were highly exposed to PBDEs, and that body burden in certain “outliers” was 4 to 7-fold higher than other cats. Using estimates of total serum lipid in cats, lipid adjusted cumulative PBDE serum levels in cats were compared to whole blood levels in U.S. adults. Cats had body burdens that were ≥ 10-fold higher. Data indicated that dry food contained relatively high levels of BDE-209, and that cats consuming dry food had significantly greater serum levels of BDE-209. Furthermore, results suggest that in cats, BDE-207 may represent an important meta-position deca debromination product. Improved understanding of how the purportedly stable BDE-209 compound undergoes metabolism and clearance is an important area of investigation. The debromination pathways suggested for these cats are seemingly in agreement with recent reports in humans and various animal species.