Comparision of the waterborne and dietary routes of exposure on the effects of Benzo(a)pyrene on biotransformation pathways in Nile tilapia (Oreochromis niloticus)

• Type: Article in International Scientific Journal
• Date: 2011

Authors

Ferreira, M (Author) Other; Rey Salgueiro, L (Author) Other; reis-henriques, ma (Author) FCUP

Journal

Title: Chemosphere

Vol. 84

Pages: 1452-1460

ISSN: 0045-6535

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 25 Citations

Scopus - 19 Citations

Other information

Authenticus ID: P-002-MXG

DOI: 10.1016/j.chemosphere.2011.04.046

Abstract (EN): BaP is one of the most studied PAH, due to its ubiquitous presence in aquatic environments and toxicity to aquatic organisms. The main goal of this study was to assess BaP effects in Nile Tilapia after water-borne and dietary exposures, through the evaluation of EROD and GST activities in liver, gills and intestine, and BaP metabolites in bile; and also to evaluate the usefulness of these commonly used biomarkers after two different routes of exposure. Waterborne exposure to BaP led to a significant induction of EROD in all tissues analyzed (644%, 1640% and 2880% in relation to solvent in liver, gill and intestine respectively) while in dietary exposures EROD was induced only in intestine (3143%) after exposure to high BaP concentrations. GST activities with CDNB were slightly induced in liver (40%) and in gill (66%) after water exposure to BaP, and in intestine after dietary exposure to low BaP concentrations (182%). BaP metabolites in bile increased after both exposure routes, and were highly correlated with EROD activity after water exposure. In summary, this work has shown that the effects of BaP on biotransformation pathways depend on the route of exposure. Moreover, barrier tissues like gills and intestine also have an important role in the first-pass metabolism of BaP, reducing the amount of parent compound that reaches the liver to be metabolized. For that reason, EROD activity as a biomarker of exposure should also be applied in extrahepatic organs, like gills and intestine, in monitoring studies. Biliaty BaP type metabolites are good reflectors of contamination levels under both exposure routes, while GST activity with CDNB as substrate, as a phase II enzyme, does not seem a reliable biomarker of exposure to BaP regardless the route of exposure.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9