title: Accumulation of dioxins and induction of cytochrome P450 1A4/1A5 enzyme activities in common cormorants from Lake Biwa, Japan: temporal trends and validation of national regulation on dioxins emission.
abstract: To validate the outcome of the national regulation on dioxins emission implemented in 1999, this study investigated temporal trends of chlorinated dioxins and related compounds (DRCs) in liver of common cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan between 2001 and 2008, as a part of the "Survey on the State of Dioxins Accumulation in Wildlife" conducted by the Ministry of the Environment, Japan. We also measured a biomarker of DRCs exposure, the cytochrome P450 1A (CYP1A)-dependent O-dealkylation activity of alkoxyresorufins (AROD), including methoxy-, ethoxy-, pentoxy- and benzyloxy-resorufins in the samples over 2001-2007. Neither TEQ nor AROD activity showed any clear declining trend over the time period, although the emission of DRCs during the corresponding period was estimated to be apparently decreasing. Our data indicate that the concentration of recalcitrant DRCs in the cormorant during 2001-2008 was scarcely affected by the national regulation on dioxins emission.
authors.affiliation: Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kubota
authors.forename: Michio X
authors.initials: MX
authors.lastname: Watanabe
authors.forename: Eun-Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Kumiko
authors.initials: K
authors.lastname: Yoneda
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Tanabe
authors.forename: Hisato
authors.initials: H
authors.lastname: Iwata
mesh_terms: D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism*; D001572:Benzofurans / Q000378:metabolism / Q000633:toxicity; D001717:Birds / Q000378:metabolism*; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D019362:Cytochrome P-450 CYP2B1 / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins / Q000378:metabolism* / Q000633:toxicity; D004784:Environmental Monitoring; D058735:Environmental Policy; D004785:Environmental Pollutants / Q000378:metabolism* / Q000633:toxicity; D004787:Environmental Pollution / Q000517:prevention & control / Q000706:statistics & numerical data; D004790:Enzyme Induction; D005260:Female; D007564:Japan; D060106:Lakes; D008099:Liver / Q000201:enzymology; D008297:Male; D011078:Polychlorinated Biphenyls / Q000378:metabolism / Q000633:toxicity; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives / Q000378:metabolism / Q000633:toxicity
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins; D004785:Environmental Pollutants; D000072317:Polychlorinated Dibenzodioxins; D003577:Cytochrome P-450 Enzyme System; D011078:Polychlorinated Biphenyls; C076307:methoxyresorufin-O-demethylase; D001189:Aryl Hydrocarbon Hydroxylases; D019363:Cytochrome P-450 CYP1A1; D019362:Cytochrome P-450 CYP2B1