PCNs, PCDD/Fs, and Non-orthoPCBs, in Water and Bottom Sediments from the Industrialized Norwegian Grenlandsfjords

Chlorinated toxic planar aromatic compounds were analyzed in the heavily industrialized Grenlandsfjords, which is a system of silled fjords in southern Norway. Surface water samples contained 7.4−160 ng/m³ polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), 14−410 ng/m³ polychlorinated naphthalenes (PCNs), and 0.31−2.4 ng/m³ non-orthochlorinated biphenyls (non-orthoPCBs). The concentrations of PCDD/Fs were about 300 times higher than in the Baltic Sea. Highest level of the compounds was found near a magnesium production plant. Hepta-CDFs and penta-CNs dominated in the inner-fjord waters, and tetra-CB 77 was the major non-orthoPCB congener. Sediment samples had PCDD/F concentration of 25−730 ng/g dw. Highest concentration was detected close to the magnesium plant. Octa-CDF dominated in the fjord sediments, especially near the magnesium plant, indicating a discharge-specific contamination with this congener. The isomer composition of PCDD/Fs and of PCNs, was unchanged when comparing samples from different layers of a sediment core from the deep anoxic water. This concludes that essentially zero degradation had occurred during ∼50 years in this environment.