title: Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepaguá Lake, Rio de Janeiro, Brazil.
abstract: The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ("Nile tilapia", Oreochromis niloticus and "acará", Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepaguá Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes.
authors.affiliation: Laboratório de Toxicologia Ambiental, Escola Nacional de Saúde Pública - FIOCRUZ, Av Brasil 4036, Prédio de Expansão do Campus, Rio de Janeiro, RJ 21041-361, Brazil.
authors.forename: Thiago E M
authors.initials: TE
authors.lastname: Parente
authors.forename: Ana C A X
authors.initials: AC
authors.lastname: De-Oliveira
authors.forename: Francisco J R
authors.initials: FJ
authors.lastname: Paumgartten
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis; D001938:Brazil; D023681:Cichlids / Q000378:metabolism*; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis / Q000378:metabolism*; D004147:Dioxins / Q000378:metabolism; D004784:Environmental Monitoring / Q000379:methods; D005506:Food Contamination; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D045483:Rivers; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*; D014876:Water Pollution
chemical_list: D015415:Biomarkers; D004147:Dioxins; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls; D019363:Cytochrome P-450 CYP1A1