title: Dispersed oil decreases the ability of a model fish (Dicentrarchus labrax) to cope with hydrostatic pressure.
abstract: Data on the biological impact of oil dispersion in deep-sea environment are scarce. Hence, the aim of this study was to evaluate the potential interest of a pressure challenge as a new experimental approach for the assessment of consequences of chemically dispersed oil, followed by a high hydrostatic pressure challenge. This work was conducted on a model fish: juvenile Dicentrarchus labrax. Seabass were exposed for 48 h to dispersant alone (nominal concentration (NC) = 4 mg L-1), mechanically dispersed oil (NC = 80 mg L-1), two chemically dispersed types of oil (NC = 50 and 80 mg L-1with a dispersant/oil ratio of 1/20), or kept in clean seawater. Fish were then exposed for 30 min at a simulated depth of 1350 m, corresponding to pressure of 136 absolute atmospheres (ATA). The probability of fish exhibiting normal activity after the pressure challenge significantly increased from 0.40 to 0.55 when they were exposed to the dispersant but decreased to 0.26 and 0.11 in the case of chemical dispersion of oil (at 50 and 80 mg L-1, respectively). The chemical dispersion at 80 mg L-1also induced an increase in probability of death after the pressure challenge (from 0.08 to 0.26). This study clearly demonstrates the ability of a pressure challenge test to give evidence of the effects of a contaminant on the capacity of fish to face hydrostatic pressure. It opens new perspectives on the analysis of the biological impact of chemical dispersion of oil at depth, especially on marine species performing vertical migrations.
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France. matthieudussauze@yahoo.fr.|Cedre, Centre de Documentation, de Recherche et d'Expérimentations sur les Pollutions Accidentelles des Eaux, 715 rue Alain Colas, CS, 41 836, Brest Cedex 2, France. matthieudussauze@yahoo.fr.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Dussauze
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Pichavant-Rafini
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Belhomme
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Buzzacott
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Killian
authors.initials: K
authors.lastname: Privat
authors.affiliation: Cedre, Centre de Documentation, de Recherche et d'Expérimentations sur les Pollutions Accidentelles des Eaux, 715 rue Alain Colas, CS, 41 836, Brest Cedex 2, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Le Floch
authors.affiliation: Total Fluides S.A, 92907, Paris la Défense, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lemaire
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Michaël
authors.initials: M
authors.lastname: Theron
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D001492:Bass; D006874:Hydrostatic Pressure; D009043:Motor Activity; D010578:Petroleum; D059392:Petroleum Pollution; D012623:Seawater; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D010578:Petroleum; D014874:Water Pollutants, Chemical
keywords: Deep sea; Dispersant; Hyperbaric challenge; Oil spill