title: Mixtures of benzo(a)pyrene, dichlorodiphenyltrichloroethane and tributyltin are more toxic to neotropical fish Rhamdia quelen than isolated exposures.
abstract: The effects of benzo(a)pyrene (BaP), dichlorodiphenyltrichloroethane (DDT) and tributyltin (TBT) association were investigated through a multi-biomarker approach. Ten Rhamdia quelen fish per group were exposed through intraperitoneal injections either to BaP (0.3; 3 or 30 mg kg(-1)), DDT or TBT (0.03; 0.3 or 3 mg kg(-1)) or BaP/DDT, BaP/TBT, DDT/TBT or BaP/DDT/TBT on their lowest doses. The experiments were divided in acute (one dose, 5-day) and sub-chronic (3 doses, 15-day). Control groups received an equal volume of PBS or canola oil (1 ml kg(-1)). The three tested contaminants altered AChE activity in brain and muscle in similar ways; the mixtures antagonized the increase evoked by the contaminants alone. BaP and TBT increased GSH content and mixtures reduced it. GPx activity was increased by DDT and TBT in the 15-day experiment and reduced by the mixtures. BaP increased GST activity in sub-chronic experiment while TBT reduced it in the acute experiment. BaP/TBT increased GST activity compared to all groups; the other mixtures reduced it compared to BaP or DDT in the 5-day experiment. BaP, DDT and TBT increased δ-ALAd activity mainly in acute exposure; the mixtures also increased δ-ALAd compared to DDT or TBT in 5 and 15-day. BaP, TBT and BaP/DDT decreased LPO in the acute experiment. In the sub-chronic experiment DDT/TBT increased LPO when compared to TBT. None of the contaminants alone altered PCO, but all mixtures increased it compared to one or another contaminant. Contaminants isolated had a more acute effect in ALT plasma level; their lowest dose, which had no effect alone, in combination has led to an increase of this enzyme, especially after 15 days. DDT increased AST in the acute and sub-chronic experiments, while TBT did the same in the latter. DDT/TBT decreased AST opposing the effect of the contaminants alone in the 5-day experiment. Hepatic lesions index could be explained by a more acute effect of the contaminants alone or combined and by activation of cell defenses after the sub-chronic exposure. TBT increased melanomacrophages counting in the 5-day experiment and the mixtures increased it in the 5 and 15-day experiments. Overall, the majority of the biomarkers pointed to a more toxic effect when these contaminants were combined, leading to unexpected toxicities compared to individual exposure scenarios. These findings are relevant considering environmental exposure conditions, since organisms are often exposed to different combinations of contaminants.
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: lolihelena@yahoo.com.br.
authors.forename: Heloísa H P
authors.initials: HH
authors.lastname: Oliveira
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: samliebel@yahoo.com.br.
authors.forename: Samuel
authors.initials: S
authors.lastname: Liebel
authors.affiliation: Departamento de Farmacologia, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: ste_bio@yahoo.com.br.
authors.forename: Stéfani C
authors.initials: SC
authors.lastname: Rossi
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: carola_barni@yahoo.com.br.
authors.forename: Ana C B
authors.initials: AC
authors.lastname: Azevedo
authors.affiliation: Departamento de Ecologia, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: bellotalopez@gmail.com.
authors.forename: Ellie A L
authors.initials: EA
authors.lastname: Barrera
authors.affiliation: Estação de Piscicultura Panamá, Est. Geral Bom Retiro, km 8, Caixa Postal 03, CEP 88.490-000, Paulo Lopes, SC, Brazil. Electronic address: juan.esquivel@unisul.br.
authors.forename: Juan Ramon Esquivel
authors.initials: JR
authors.lastname: Garcia
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: s_grotzner@yahoo.com.br.
authors.forename: Sônia Regina
authors.initials: SR
authors.lastname: Grötzner
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: filipak@ufpr.br.
authors.forename: Francisco Filipak
authors.initials: FF
authors.lastname: Neto
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: mafrandi@ufpr.br.
authors.forename: Marco A F
authors.initials: MA
authors.lastname: Randi
authors.affiliation: Departamento de Biologia Celular, Universidade Federal do Paraná, Caixa Postal 19.031, CEP 81.531-990, Curitiba, PR, Brazil. Electronic address: ciro@ufpr.br.
authors.forename: Ciro A O
authors.initials: CA
authors.lastname: Ribeiro
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000410:Alanine Transaminase / Q000097:blood; D000622:Aminolevulinic Acid / Q000378:metabolism; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001564:Benzo(a)pyrene / Q000633:toxicity*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002397:Catfishes / Q000097:blood / Q000378:metabolism; D003634:DDT / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D009132:Muscles / Q000187:drug effects / Q000378:metabolism; D014220:Trialkyltin Compounds / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene; C011559:tributyltin; D000622:Aminolevulinic Acid; D003634:DDT; D005979:Glutathione Peroxidase; D005982:Glutathione Transferase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D000110:Acetylcholinesterase; D005978:Glutathione
keywords: Biomarker; Histopathology; Mixture; Neotropical fish; Organic pollutant; Toxicity