Cod caged as canaries in polluted Kollevåg
Waste from garbage disposal can affect our environment. Kollevåg, a bay situated in Askøy outside of Bergen, was utilized as a waste disposal from 1930 to 1975. After terminating the disposal, the garbage was covered by sand and stone and a recreational area was opened in 1983. However, in 2005, sediment pollution was discovered in the Kollevåg area due to disturbance of the capping. Actions to repair the capping are being prepared. In the dCod 1.0 project, we wanted to investigate the environmental effects of the pollution on Atlantic cod prior to and after improvements performed in Kollevåg. Groups of Atlantic cod (n=22) were placed in cages in different locations in Kollevåg and at a reference location from August to October 2016. After six weeks the fish were collected, euthanized and sampled. Bile were analyzed for PAH metabolites using HPLC. Mucus and blood plasma are being analyzed for the presence of vitellogenin (VTG), a common biomarker for endocrine disrupting compounds (EDCs), using ELISA. The liver tissue is being utilized for qPCR analysis to assess gene expression of common biomarkers involved in contaminant exposure (VTG, CYP1A), in addition to other genes known to be affected by relevant contaminants such as PCBs. The liver transcriptome will be analyzed by RNA sequencing methdology. Liver samples were also taken for analysis of chemical contaminants using target and non-target analyses.
In total, more than 1000 samples were collected from 82 fish during the sampling campaign on board R/V Hans Brattstrøm. These are now being analyzed.