Major oil discharges such as the one from the drilling rig Deepwater Horizon or the grounding of the Full City off Langesund, Norway, have wrought havoc on the natural environment. The research project Toxprof examined the impacts of oil discharges along the coast of Europe. The researchers studied the effects of common Arabian light crude as well as oil from the Norwegian Ekofisk field, in addition to the diesel fuel commonly used by ships.

Simulated oil spills
The experiments were carried out at the University of Oslo’s marine biological station at Drøbak, located on the Oslo Fjord. Seawater was pumped through coarse sand containing oil that was partially broken down by UV radiation. The oil then floated to aquariums containing cod, mussels or spotted goby. In this way the researchers could control the concentrations of the oils’ environmentally hazardous components.

“We tested how the broken down oils affected cod, mussels and spotted goby ,” says Ketil Hylland, Professor of Toxicology at the University of Oslo’s Department of Biology. “From the experiments we were able to work out clear profiles for the impacts of the selected oils, yielding some important answers as to which substances are most toxic.”

“The project is realistic, simulating what occurs in the natural environment in the wake of an oil spill, where the oil ends up in sand and gravel and eventually seeps into the water masses. We measured a variety of biomarkers in the gills and liver of the cod and the digestive glands and gills of the mussels. The trials showed that the effects changed over time and lasted more than three weeks.”

The Toxprof project was a collaborative research effort between Norway, the UK, Spain and France. The Norwegian Institute for Water Research (NIVA) and the University of Oslo’s Department of Biology, the two Norwegian participants, received funding under the Research Council of Norway’s Oceans and Coastal Areas Programme (HAVKYST).