EFFECTS OF CONTAMINANTS IN ROUNDNOSE GRENADIER (CORYPHAENOIDES RUPESTRIS) AND NORWAY LOBSTER (NEPHROPS-NORVEGICUS) AND CONTAMINANT LEVELS IN MUSSELS (MYTILUS-EDULIS) IN THE SKAGERRAK AND KATTEGAT COMPARED TO THE FAROE ISLANDS

in situ biomonitoring of roundnose grenadier (Coryphaenoides rupestris ) and Norway lobster (Nephrops norvegicus) and measurements of polluta nt levels in caged common mussel (Mytilus edulis) were used to assess the environmental impact of contaminants in the Skagerrak and Kattegat and near the Faroe Islands. By comparing the responses of a suite of established and potential biomarkers, i.e. different liver detoxificat ion enzymes and histopathology in roundnose grenadier in the Skagerrak , and at a reference site off the Faroe islands, evidence was found th at the deeper parts of the Skagerrak are affected by anthropogenic con taminants. Levels of polycyclic aromatic hydrocarbons (PAH) and organo chlorines in caged mussels were compared with those in sediment. The S kagerrak/Kattegat area was found to be more polluted than the Faroe ar ea and the caged mussels bioaccumulated the PAHs to a higher degree th an the organochlorines. This seems to indicate that the PAHs in the se diments are more bioavailable than the organochlorines and that the in duced ethoxyresorufin-O-deethylase activities observed in Skagerrak ro undnose grenadier may be due to RAN exposure. The Norway lobster accum ulated manganese to Various degrees in the different parts of the orga nism. The excretion rate of manganese could not cope with the uptake r ate at higher exposure concentrations. Enhanced manganese concentratio ns, especially in the gills and haemolymph, seem to be a useful indica tion of increased manganese levels in the water. Hypoxia makes sedimen t-bound manganese much more bioavailable. The elevated levels of manga nese in Norway lobster from the Skagerrak/Kattegat area therefore seem to reflect the increasing occurrence of hypoxic conditions in the Kat tegat and coastal areas of the Skagerrak. Accumulated manganese in Nor way lobster may thus serve as a biomarker of hypoxia. In conclusion, t he use of a suite of different biomarkers in ecotoxicological and ecop hysiological studies and analyses of contaminant levels have provided evidence of a large-scale environmental impact of pollutants and nutri ents in the Skagerrak/Kattegat area. This should lead to further effor ts to decrease transport into and deposition of waste compounds in the sea.