title: Chemical comparison and acute toxicity of water accommodated fraction (WAF) of source and field collected Macondo oils from the Deepwater Horizon spill.
abstract: Two Source oils and five field collected oil residues from the Deepwater Horizon incident were chemically characterized. Water accommodated fractions (WAFs) of the Source oils and two of the field-weathered oils were prepared to evaluate the impact of natural weathering on the chemical composition and the acute toxicity of the WAFs. Toxicity test species representing different tropic levels were used (the primary producer Skeletonema costatum (algae) and the herbivorous copepod Acartia tonsa). The results suggest that the potential for acute toxicity is higher in WAFs from non-weathered oils than WAFs from the field weathered oils. The Source oils contained a large fraction of soluble and bioavailable components (such as BTEX (benzene, toluene, ethyl benzene, xylenes) and naphthalene), whereas in the surface collected oils these components were depleted by dissolution into the water column as the oil rose to the surface and by evaporative loss after reaching the sea surface.
authors.affiliation: SINTEF Materials and Chemistry, NO-7465 Trondheim, Norway. Electronic address: livgurif@sintef.no.
authors.forename: Liv-Guri
authors.initials: LG
authors.lastname: Faksness
authors.affiliation: BioTrix, NO-7022 Trondheim, Norway.
authors.forename: Dag
authors.initials: D
authors.lastname: Altin
authors.affiliation: SINTEF Materials and Chemistry, NO-7465 Trondheim, Norway.
authors.forename: Trond
authors.initials: T
authors.lastname: Nordtug
authors.affiliation: SINTEF Materials and Chemistry, NO-7465 Trondheim, Norway.
authors.forename: Per S
authors.initials: PS
authors.lastname: Daling
authors.affiliation: SINTEF Materials and Chemistry, NO-7465 Trondheim, Norway.
authors.forename: Bjørn Henrik
authors.initials: BH
authors.lastname: Hansen
mesh_terms: D000818:Animals; D033342:Copepoda; D017377:Diatoms; D009821:Oils / Q000032:analysis; D010578:Petroleum / Q000032:analysis* / Q000633:toxicity; D059392:Petroleum Pollution; D023382:Toxicity Tests, Acute; D014867:Water / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity; D014887:Weather
chemical_list: D009821:Oils; D010578:Petroleum; D014874:Water Pollutants, Chemical; D014867:Water
keywords: Acute toxicity; Chemistry; Deepwater Horizon; Oil spill; Petroleum hydrocarbons; WAF