Nano-contamination of aquatic organisms by inorganic particles : trophic transfers and toxic impacts

• Main Author: Perrier, Fanny
• Other Authors: Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux, Olivier Simon, Agnès Feurtet-Mazel
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: CCSD 2017
• Subjects: Gold nanoparticles; Chronic exposure; Trophic transfer; Aquatic ecosystem; Algae - natural biofilms; Bivalve - grazer fish; Predatory fish; Histology; Transcriptomic; High throughput sequencing; Nanoparticules d’or; Expositions chroniques; Transfert trophique; Écosystème aquatique; Algues-biofilms naturels; Bivalve-poisson brouteur; Poisson prédateur; Histologie; Transcriptomique; Séquençage haut-débit; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology; European eel
• Online Access: https://theses.hal.science/tel-01739724; https://theses.hal.science/tel-01739724v1/document; https://theses.hal.science/tel-01739724v1/file/PERRIER_FANNY_2017.pdf

Due to an increasing and massive use, engineered nanoparticles are raising as potentialemerging contaminants in the environment, including aquatic ecosystems. While trophictransfer appears to constitute a major exposure route for organisms, scientific literature hasdifficulties to respond to the questions raised to explore the range of the interactions existingbetween nanoparticles and living organisms at different scales from the trophic interactionsto the cellular impacts. This problem is partly due to experimental difficulties inherent tothis exposure type. For this work performed in controlled laboratory conditions, sphericalgold nanoparticles (10 nm, coated with PEG-amines, positively charged) were chosen tostudy the trophic transfer and toxic effects on aquatic organisms. Trophic chains concernedseveral trophic levels (up to three) with a variety of species considered : the basis of thetrophic web with natural biofilms or microalgae, intermediate levels with grazing fish orsuspensivorous bivalves, and up to top food chain organisms, with the European eel, a carnivorousfish.With relatively low doses for exposures, this work tends to represent environmentalconditions. Integrative methodological approaches from subcellular to tissue levels(RT-qPCR, RNA-sequencing, histology) were performed in order to assess toxic impacts.The results indicate a high retention capacity of nanoparticles by natural biofilms. Followinga 21-day exposure, gold quantifications reveal a transfer from biofilms to grazing fish, witha gold distribution in all organs. Moreover, this transfer is associated with an inflammatoryresponse according to the histological lesions observed in the liver, spleen and muscle ofexposed fish. A longer food chain, with three trophic levels involving microalgae - bivalves- European eels, is set up to give a better representation of the complexity of trophic interactionsin the aquatic environment. It shows a significant transfer to the predatory fish.Transcriptomic analyses, using the RNA-sequencing ...