| Summary: | Release of chemicals from anthropogenic activities is considered a substantial threat to the global environment. Marine ecosystems are sinks for accumulation of contaminants, therefore marine organisms are highly susceptible to contaminant exposure and possible adverse effects. Importantly, organisms are continuously exposed to complex mixtures of chemicals and interactions among these chemicals may occur. Thus, acquiring knowledge of which components that provoke certain effects can be challenging and needs to be addressed in detail. The main objective of this dissertation was to assess the biological responses of Atlantic cod (Gadus morhua) exposed to contaminant mixtures, focusing primarily on the liver as the target organ for effects. An additional aspect was to investigate mixture effects of contaminants using different experimental approaches, including a field/caging study (Paper I), an in vivo exposure study (Paper II), and an ex vivo exposure study with precision-cut liver slices (PCLS) (Paper III). The caging and in vivo studies (Paper I and II) assessed effects of environmentally relevant concentrations of contaminants, whereas a mechanistic approach with a wider range of concentrations was applied in the PCLS study (Paper III). While Paper I included several groups of environmental contaminants, the contaminants investigated in the studies comprising this dissertation were the polycyclic aromatic hydrocarbons (PAHs) (Paper II) and the per- and polyfluoroalkyl substances (PFAS) (Paper II and III). The distribution and possible adverse effects of these contaminants have previously been studied in isolation in marine species, however, limited research exists on their combined effects. In Paper I, an in situ approach was applied to assess whether Atlantic cod would be affected by contaminants leaking from a capped waste disposal site in the bay of Kollevåg in Western Norway. To this end, farmed juveniles of Atlantic cod were caged for six weeks at different locations within Kollevåg bay, with three cages ...
|
|---|