Organohalogen Compounds in Pet Dog and Cat: Do Pets Biotransform Natural Brominated Products in Food to Harmful Hydroxlated Substances?

• DOI: 10.1021/acs.est.5b04216
• Publication Date: 2015-12-02T14:46:08Z
• Authors: Hazuki Mizukawa; Kei Nomiyama; Susumu Nakatsu; Hisato Iwata; Jean Yoo; Akira Kubota; Miyuki Yamamoto; Mayumi Ishizuka; Yoshinori Ikenaka; Shouta M. M. Naka...; Tatsuya Kunisue; Shinsuke Tanabe
• Keywords: Biotransformation

There are growing concerns about the increase in hyperthyroidism pet cats due to exposure organohalogen contaminants and their hydroxylated metabolites. This study investigated blood polychlorinated biphenyls (PCBs) polybrominated diphenyl ethers (PBDEs) methoxylated derivatives (OH-PCBs, OH-PBDEs, MeO-PBDEs), dogs cats. We also measured residue levels of these compounds commercially available foods. Chemical analyses PCBs OH-PCBs showed that OH-PCB were 1 2 orders magnitude lower cat dog food products than blood, suggesting origin is ingested with food. The major congeners OH-/MeO-PBDEs identified both natural (6OH-/MeO-BDE47 2′OH-/MeO-BDE68) from marine organisms. In particular, higher concentrations 6OH-BDE47 2′OH-BDE68 two MeO-PBDE observed although MeO-BDEs dominant foods, efficient biotransformation 6MeO-BDE47 performed vitro demethylation experiments confirm MeO-PBDEs OH-PBDEs using liver microsomes. results 2′MeO-BDE68 demethylated animals, whereas no metabolite BDE47 was detected. present suggests exposed through containing fish flavors derived CYP-dependent naturally occurring congeners, not hydroxylation PBDEs.