title: High polybrominated diphenyl ether levels in California house cats: house dust a primary source?
abstract: Polybrominated diphenyl ethers (PBDEs) are brominated flame retardants that act as endocrine disruptors, affecting thyroid hormone homeostasis. As a follow-up to a recent study showing high PBDE levels in household cats and linking PBDE levels with cat hyperthyroidism, we measured PBDEs, polychlorinated biphenyls (PCBs), and organochlorinated pesticides (OCPs) in serum samples from 26 California household cats (16 hyperthyroid, 10 controls) using liquid-liquid extraction and high-resolution gas chromatography/high-resolution mass spectrometry. In the present pilot study, we found that PBDE levels in California house cats were extremely high (ΣPBDEs median = 2,904 ng/g lipid; range, 631-22,537 ng/g lipid). This is approximately 50 times higher than levels in California residents (ΣPBDEs geomean = 62 ± 8.9 ng/g lipid, National Health and Nutrition Examination Survey), who have among the highest human levels in the world. Polybrominated diphenyl ethers congener patterns (BDE-99 major congener, BDE-209 significant) differed markedly from patterns found in California residents (BDE-47 major) or wildlife but resembled patterns found in house dust. Polychlorinated biphenyls and OCPs in cats were highly correlated, consistent with a shared dietary source or pathway of exposure, but did not correlate with PBDEs. This suggests a different source or pathway of exposure for PBDEs, which was most likely house dust. The authors found no evidence that linked levels of PBDEs, PCBs, or OCPs with hyperthyroidism. This may be because of the small sample size, competing or confounding risk factors, or complicated causal mechanisms.
authors: Environmental Chemistry Laboratory, California Department of Toxic Substances Control, California Environmental Protection Agency, Berkeley, California, USA. wguo@dtsc.ca
authors: Weihong
authors: W
authors: Guo
authors: June-Soo
authors: JS
authors: Park
authors: Yunzhu
authors: Y
authors: Wang
authors: Steve
authors: S
authors: Gardner
authors: Christina
authors: C
authors: Baek
authors: Myrto
authors: M
authors: Petreas
authors: Kim
authors: K
authors: Hooper
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000032:analysis / Q000378:metabolism*; D016902:Air Pollution, Indoor / Q000706:statistics & numerical data; D000818:Animals; D002140:California; D002415:Cats; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring; D005411:Flame Retardants / Q000032:analysis / Q000378:metabolism; D055768:Halogenated Diphenyl Ethers / Q000378:metabolism*; D006801:Humans; D009749:Nutrition Surveys; D010865:Pilot Projects; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism
chemical_list: D000393:Air Pollutants; D004391:Dust; D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D011078:Polychlorinated Biphenyls