Assessment of sediment toxicity during anaerobic biodegradation of vegetable oil using Microtox and Hyalella azteca bioassays.
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.
Li
Zhengkai
Z
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
Lee
Kenneth
K
Cobanli
Susan E
SE
King
Thomas
T
Wrenn
Brian A
BA
Doe
Kenneth G
KG
Jackman
Paula M
PM
Venosa
Albert D
AD
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*
D010938:Plant Oils; D014874:Water Pollutants, Chemical