Aarhus University Seal

Arctic marine potential of microbial oil degradation

A new report from DCE – Danish Centre for Environment and Energy details research into the potential of microbial oil degradation in the Arctic Ocean.

Oil spills at sea can originate from different sources such as land runoff, transport at sea and offshore drilling. (Photo: Colourbox)

The main sources of oil pollution in the sea come from the offshore exploitation and transport of oil, but operational spills of oil from ships can also have a significant impact. Runoff from land, wastewater discharge and atmospheric deposition contribute to the load at a regional scale. Furthermore, natural oil seeps in the ocean may act as a potential source at some locations. However, tanker accidents and blowouts are the most important sources of high-volume oil spills.

The DCE report aims to collect and analyze relevant existing knowledge about microbial degradation of oil in the seawater around Greenland to add to the knowledge base for developing contingency plans and perform Net Environmental Benefit Analyses (NEBAs) for Greenland in relation to an oil spill from oil exploration activities and shipping in Arctic waters.

Existing studies on oil degradation have primarily focused on the total removal of oil within certain boiling point intervals. Some studies have been supplemented with analyses of a few oil components such as benzene, toluene, ethylbenzene and xylenes (BTEX) and EPA16 (Polycyclic Aromatic Hydrocarbons, PAHs). Of the oil components, alkanes have the lowest toxicity and a relatively high biodegradability. However, the heavy aromatic fraction is more toxic and is slowly degradable. Results based solely on total oil may underestimate the toxicity of oil and overestimate the degradation of potentially toxic oil components in the environment.

The existing knowledge about biodegradation of oil in seawater in Greenland waters is presently limited to one study, which has a direct focus on oil degradation in seawater in Disko Bay. Hence, to enhance our knowledge about the marine oil biodegradation potential in Greenland, it is recommended that future research should focus on:

1.       Getting a more generalized picture of the oil degradation potential in the seawater around Greenland

2.       Identifying Greenlandic localities showing similar oil-degrading characteristics.

3.       Linking the degradation potential with environmental parameters and toxic effects.

Finally, increased toxicity of oil exposed to photochemical reactions is area topic deserving more research as such photochemical processes may be much more critical in Greenland during summer with all-day sunlight.

Read the full report here

For more information, please contact Susse Wegeberg

E-mail: sw@bios.au.dk

Telephone: +4587158669