Evaluation of biological effects of chemical contaminants on juvenile marine fish : a multibiomarqueur approach under laboratory and field conditions

• Main Author: Kerambrun, Élodie
• Other Authors: Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Nord ), Université du Littoral Côte d'Opale, Rachid Amara, Françoise Henry
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2011
• Subjects: Ecotoxicology; Juvenile fish; Metal; PAHs; Caging; EROD; Growth; Condition; Lipidic index; GST; Écotoxicologie; Juvéniles de poissons; Métaux; HAPs; Biomarqueurs; Croissance; Indices de condition; [SDV.SA]Life Sciences [q-bio]/Agricultural sciences; Turbot
• Online Access: https://theses.hal.science/tel-00841588; https://theses.hal.science/tel-00841588/document; https://theses.hal.science/tel-00841588/file/KERAMBRUN.pdf

Evaluation of pollutant effects in environment is one of the major issues of the European Water Framework Directive 2000. Regulations have particularly the objective to reach to a good chemical and ecological status of water bodies. In this context, the aim of our study was to develop a multibiomarker approach on juvenile marine fish in order to evaluate the biological effects of chemical pollution in coastal areas. Molecular detoxification parameters (EROD, GST) and an antioxidant enzyme (CAT) were used as early warning tools of toxicity allowing the prevention of irreversible damages. In parallel, different physiological biomarkers (somatic and recent growth, RNA:DNA ratio, morphometric and lipidic indices) were analysed as reflecting damages on juveniles health. Sensitivity and relevance of molecular and physiological biomarkers were tested experimentally on juvenile : i) sea bass exposed to acute petroleum pollution, ii) sea bass and turbot submitted to a mix of contaminants in environmental concentrations during controlled and semi-controlled (caging) conditions. Our results show the ability of EROD, and in lower degree the GST, to detect short exposure (2 and 4 days) of organisms to petroleum and to reflect their deleterious effects on fish health. This relationship between molecular and physiological biomarkers was more difficultly established under multiple pollutions. Growth and condition indices were found to be more sensitive to the different levels of chemical contamination analysed (metal, PAHs). Their analyses allowed us to evaluate the weakened condition of organisms caged in the harbour area during 38 days. This caging experiment was relevant especially for juvenile sea bass in which no physiological stress was detected in the reference station. Deleterious effects of chemical contaminant on turbot juvenile health were also observed in controlled condition after 21 days exposure to the same harbour sediments and to an estuarine sediment. In complement to these experiments, a field study was ...