title: Assessment of sediment toxicity during anaerobic biodegradation of vegetable oil using Microtox and Hyalella azteca bioassays.
abstract: The potential ecological impacts of anaerobic degradation of vegetable oil on freshwater sediments were investigated. Sediment toxicity was evaluated using two regulatory biotests: the Microtox Solid Phase Test and an amphipod (Hyalella azteca) bioassay. The results of the Microtox test showed that the toxicity of the vegetable-oil-contaminated sediments (about 17-33 g oil/kg dry sediments) increased after 2 weeks incubation and then decreased to near background levels after incubation for 8 weeks under anaerobic conditions. The amphipod toxicity bioassay showed that the toxicity of fresh contaminated sediments decreased over time and returned to background levels within 8 weeks. These results suggest that the impact of vegetable oils on organisms within sediments may be limited. To account for the significance of environmental conditions, additional studies over a wide range of incubation conditions (e.g., temperature, nutrient concentration) and other test organisms at various trophic levels are recommended for both acute and chronic toxicity assessment.
authors.affiliation: Center for Offshore Oil and Gas Environmental Research, Bedford Institute of Oceanography, Fisheries and Oceans Canada, Dartmouth, Nova Scotia, Canada B2Y 4A2. liz@mar.dfo-mpo.gc.ca
authors.forename: Zhengkai
authors.initials: Z
authors.lastname: Li
authors.forename: Kenneth
authors.initials: K
authors.lastname: Lee
authors.forename: Susan E
authors.initials: SE
authors.lastname: Cobanli
authors.forename: Thomas
authors.initials: T
authors.lastname: King
authors.forename: Brian A
authors.initials: BA
authors.lastname: Wrenn
authors.forename: Kenneth G
authors.initials: KG
authors.lastname: Doe
authors.forename: Paula M
authors.initials: PM
authors.lastname: Jackman
authors.forename: Albert D
authors.initials: AD
authors.lastname: Venosa
mesh_terms: D033304:Amphipoda / Q000187:drug effects* / Q000378:metabolism; D000693:Anaerobiosis; D000818:Animals; D001673:Biodegradation, Environmental; D001681:Biological Assay; D020387:Food Chain; D005618:Fresh Water; D019015:Geologic Sediments / Q000737:chemistry*; D010938:Plant Oils / Q000378:metabolism*; D018570:Risk Assessment; D013696:Temperature; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D010938:Plant Oils; D014874:Water Pollutants, Chemical