title: Sensitivity of the deep-sea amphipod Eurythenes gryllus to chemically dispersed oil.
abstract: In the context of an oil spill accident and the following oil spill response, much attention is given to the use of dispersants. Dispersants are used to disperse an oil slick from the sea surface into the water column generating a cloud of dispersed oil droplets. The main consequence is an increasing of the sea water-oil interface which induces an increase of the oil biodegradation. Hence, the use of dispersants can be effective in preventing oiling of sensitive coastal environments. Also, in case of an oil blowout from the seabed, subsea injection of dispersants may offer some benefits compared to containment and recovery of the oil or in situ burning operation at the sea surface. However, biological effects of dispersed oil are poorly understood for deep-sea species. Most effects studies on dispersed oil and also other oil-related compounds have been focusing on more shallow water species. This is the first approach to assess the sensitivity of a macro-benthic deep-sea organism to dispersed oil. This paper describes a toxicity test which was performed on the macro-benthic deep-sea amphipod (Eurythenes gryllus) to determine the concentration causing lethality to 50% of test individuals (LC50) after an exposure to dispersed Brut Arabian Light (BAL) oil. The LC50 (24 h) was 101 and 24 mg L(-1) after 72 h and 12 mg L(-1) at 96 h. Based on EPA scale of toxicity categories to aquatic organisms, an LC50 (96 h) of 12 mg L(-1) indicates that the dispersed oil was slightly to moderately toxic to E. gryllus. As an attempt to compare our results to others, a literature study was performed. Due to limited amount of data available for dispersed oil and amphipods, information on other crustacean species and other oil-related compounds was also collected. Only one study on dispersed oil and amphipods was found, the LC50 value in this study was similar to the LC50 value of E. gryllus in our study. Since toxicity data are important input to risk assessment and net environmental benefit analyses, and since such data are generally lacking on deep-sea species, the data set produced in this study is of interest to the industry, stakeholders, environmental management, and ecotoxicologists. However, studies including more deep-sea species covering different functional groups are needed to evaluate the sensitivity of the deep-sea compartments to dispersed oil relative to other environmental compartments.
authors.affiliation: Akvaplan-niva, High North Research Centre for Climate and the Environment, 9296, Tromsø, Norway. gho@akvaplan.niva.no.
authors.forename: Gro Harlaug
authors.initials: GH
authors.lastname: Olsen
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: Nathalie
authors.initials: N
authors.lastname: Coquillé
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: Stephane
authors.initials: S
authors.lastname: Le Floch
authors.affiliation: Akvaplan-niva, High North Research Centre for Climate and the Environment, 9296, Tromsø, Norway.
authors.forename: Perrine
authors.initials: P
authors.lastname: Geraudie
authors.affiliation: Laboratoire ORPHY EA4324, Université de Bretagne Occidentale, 6 Avenue le Gorgeu, CS 93 837, 29 238, Brest Cedex 3, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Dussauze
authors.affiliation: Total Fluides SAS, 24 cours Michelet-La Defense 10, 92069, Paris La Défense Cedex, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lemaire
authors.affiliation: Akvaplan-niva, High North Research Centre for Climate and the Environment, 9296, Tromsø, Norway.
authors.forename: Lionel
authors.initials: L
authors.lastname: Camus
mesh_terms: D033304:Amphipoda / Q000187:drug effects*; D000818:Animals; D001673:Biodegradation, Environmental; D007928:Lethal Dose 50; D010578:Petroleum / Q000032:analysis / Q000633:toxicity*; D059392:Petroleum Pollution / Q000032:analysis / Q000517:prevention & control*; D012623:Seawater / Q000737:chemistry*; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D010578:Petroleum; D014874:Water Pollutants, Chemical
keywords: Amphipod; Deep-sea; Dispersed oil; Ecotoxicology; Lc50; Petroleum