Biodegradation of crude oil in Arctic subsurface water from the Disko Bay (Greenland) is limited.
Biological degradation is the main process for oil degradation in a subsurface oil plume. There is, however, little information on the biodegradation potential of Arctic, marine subsurface environments. We therefore investigated oil biodegradation in microcosms at 2 °C containing Arctic subsurface seawater from the Disko Bay (Greenland) and crude oil at three concentrations of 2.5-10 mg/L. Within 71 days, the total petroleum hydrocarbon concentration decreased only by 18 ± 18% for an initial concentration of 5 mg/L. The saturated alkanes nC13-nC30 and the isoprenoids iC18-iC21 were biodegraded at all concentrations indicating a substantial potential for biodegradation of these compound classes. Polycyclic aromatic compounds (PACs) disappeared from the oil phase, but dissolution was the main process of removal. Analysis of diagnostic ratios indicated almost no PAC biodegradation except for the C1-naphthalenes. To conclude, the marine subsurface microorganisms from the Disko Bay had the potential for biodegradation of n-alkanes and isoprenoids while the metabolically complex and toxic PACs and their alkylated homologs remained almost unchanged.
Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
Katrine
K
Scheibye
Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark. Electronic address: jch@plen.ku.dk.
Jan H
JH
Christensen
Geological Survey of Denmark and Greenland, Department of Geochemistry, Øster Voldgade 10, 1350 København K, Denmark.
Anders R
AR
Johnsen
D001110:Arctic Regions; D061006:Bays; D001673:Biodegradation, Environmental; D006116:Greenland; D009281:Naphthalenes / Q000737:chemistry; D010578:Petroleum / Q000032:analysis; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis
D009281:Naphthalenes; D010578:Petroleum; D014874:Water Pollutants, Chemical
Arctic marine environment; Oil biodegradation; Polycyclic aromatic compounds (PACs); Subsurface oil spill