Fate of Pulp Mill Organochlorines in the Gulf of Bothnia Sediments

Adsorbable organic halogen (AOX), extractable organic halogen (EOX), free chlorophenols (FPCP), and bound chlorophenols (BPCP) were measured in dated sediment cores from four brackish water areas in a pulp mill recipient archipelago and a nearby fresh water (reference) area. Pulp mill organochlorines accumulated in nearby recipient bottoms and concentrations decreased rapidly with steep gradient outward. History, increase, and decrease of organochlorine levels in mill effluents were clearly reflected in annual deposition rates. Some transportation of organochlorines to older sediment layers was indicated. AOX and EOX levels correlated significantly.