Polycyclic aromatic hydrocarbons (PAH) have been determined, by glass capillary gas chromatography, in two species of bivalves (Mytilus edulis and Modiolus modiolus) and sediments of Saudafjorden, Norway. The PAH observed are derived from waste effluents from a ferro alloy smelter. Up to 34 PAH compounds were identified, including some reported to be carcinogenic. The concentrations decreased rapidly with distance from the source and with sediment depth, but could be traced more than 15 km from the source. Relative abundance of various PAH did not change significantly in the mussels collected from the head to the mouth of the fjord. In the sediments, however, phenanthrene increased from minor importance to dominance towards the mouth, whereas the relative content of anthracene and benzo [a]pyrene decreased. The results are compared with observations from other marine localities and discussed in relation to transport processes, biodegradation and chemical transformation in the sediments.