Levels of selected contaminants have been determined in sediment, blue mussel, seeweed and fish from harbour areas in Harstad, Tromsø, Hammerfest and Honningsvåg in northern Norway. The following contaminants were included in the study: PAH, PCB, 5CB, HCB, OCS, HCH, DDT, DDE, DDD, TBT, Cd, Cu, Hg, Pb, Zn and Li. A few samples were also analysed for dioxines (PCDD and PCDF), non-ortho PCBs and PCN. The results were compared with the Norwegian State Pollution Control Authorities classification system for marine sediments (Molvær et al. 1997). Elevated (and in most cases very high) levels of most of the measured contaminants were found in all the investigated harbour areas.