title: Removal by sorption and in situ biodegradation of oil spills limits damage to marine biota: a laboratory simulation.
abstract: This study examined the efficiency of cotton grass fibers in removing diesel oil from the surface of water in conditions prevailing in the Baltic Sea. The effect of low temperature, salinity, and bacterial amendments were tested in laboratory-scale set-ups, whereas 600-L mesocosms filled with Baltic Sea water were used for testing the effects of diesel oil and rapid removal of the oil on microorganisms, phytoplankton, and mussels. Cotton grass proved to be an excellent sorbent for diesel oil from the water surface at a low temperature. Inoculation with diesel-enriched microorganisms enhanced degradation of oil significantly in laboratory-scale experiments. In mesocosm experiments, the addition of diesel oil (0.66 mg L(-1), 0.533 L m(-2)) to the basins resulted in higher microbial density than in all other basins, including inoculated ones, suggesting that the Baltic Sea contains indigenous hydrocarbon degraders. The removal of oil with cotton grass significantly improved the survival of mussels in the mesocosm tests: 100% mortality in diesel basins versus 0% mortality in basins with cotton grass, respectively. However, the surviving mussels suffered from histopathological changes such as inflammatory responses, degenerations, and cell death. The observed rescuing effect was observable even when the cotton grass-bound oil was left in the water. The results underline the importance of rapid action in limiting damage caused by oil spills.
authors.affiliation: Department of Ecological and Environmental Sciences, University of Helsinki, Finland. Sonja.Suni@helsinki.fi
authors.forename: Sonja
authors.initials: S
authors.lastname: Suni
authors.forename: Kaisa
authors.initials: K
authors.lastname: Koskinen
authors.forename: Sari
authors.initials: S
authors.lastname: Kauppi
authors.forename: Emilia
authors.initials: E
authors.lastname: Hannula
authors.forename: Tuukka
authors.initials: T
authors.lastname: Ryynänen
authors.forename: Annika
authors.initials: A
authors.lastname: Aalto
authors.forename: Jenni
authors.initials: J
authors.lastname: Jäänheimo
authors.forename: Johanna
authors.initials: J
authors.lastname: Ikävalko
authors.forename: Martin
authors.initials: M
authors.lastname: Romantschuk
mesh_terms: D000327:Adsorption; D000818:Animals; D001454:Baltic States; D001673:Biodegradation, Environmental; D044822:Biodiversity; D049872:Bivalvia; D019411:Clinical Laboratory Techniques; D004190:Disasters; D006838:Hydrocarbons / Q000378:metabolism; D008386:Marine Biology; D008954:Models, Biological; D009792:Oceans and Seas; D010578:Petroleum / Q000378:metabolism*; D012989:Soil Pollutants / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D006838:Hydrocarbons; D010578:Petroleum; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical