title: The effect of long-term depuration on phase I and phase II biotransformation in mullets (Mugil cephalus) chronically exposed to pollutants in River Douro Estuary, Portugal.
abstract: Pollutants such polycyclic aromatic hydrocarbons (PAHs) are released into the environment by urban communities and industries and the enzymes that catalyse the biotransformation of pollutants play a key role regarding the accumulation of these compounds in fish species inhabiting these areas. In this study the relationship between phase I (EROD activity) and phase II (GST activity) and PAH metabolites was measured in grey mullet (Mugil cephalus) after capture in the Douro estuary, and after long-term depuration in an unpolluted laboratory environment. The results showed a significant decrease in EROD activity after 1 month and in bile metabolites after 4 months in captivity, with both maintaining reduced levels at 4 and 8 months depuration. Liver GST activity did not showed significant changes. This study provides evidence that Douro estuary waters contain bioavailable PAHs that can be associated with the induction of cytochrome P450, and that mullets have the ability to metabolise and eliminate PAHs.
authors.affiliation: ICBAS -- Instituto de Ciências Biomédicas de Abel Salazar, Largo Professor Abel Salazar, 2, 4099-003 Porto, Portugal. mferreira@cimar.org
authors.forename: M
authors.initials: M
authors.lastname: Ferreira
authors.forename: P
authors.initials: P
authors.lastname: Moradas-Ferreira
authors.forename: M A
authors.initials: MA
authors.lastname: Reis-Henriques
mesh_terms: D000818:Animals; D001580:Benzopyrenes / Q000032:analysis; D001646:Bile / Q000737:chemistry; D001664:Biliverdine / Q000032:analysis; D001711:Biotransformation / Q000187:drug effects; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis / Q000378:metabolism; D004781:Environmental Exposure; D005982:Glutathione Transferase / Q000032:analysis / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D010616:Phenanthrenes / Q000032:analysis; D011174:Portugal; D011721:Pyrenes / Q000032:analysis; D023701:Smegmamorpha / Q000378:metabolism*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics* / Q000633:toxicity; D014877:Water Pollution, Chemical
chemical_list: D001580:Benzopyrenes; D010616:Phenanthrenes; D011721:Pyrenes; D014874:Water Pollutants, Chemical; C031181:phenanthrene; C030984:pyrene; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase; D001664:Biliverdine