Characterization of chemical contamination in shallow-water estuarine habitats of an industrialized river. Part II. Metals

The lower six miles of the tidal portion of the Passaic River (Study Area) has long been heavily industrialized. The objectives of this study were to: quantify, the present extent and magnitude of metals contamination in surface sediments in the Study Area, evaluate the contamination in the Study Area relative to a reference area and surrounding regional waterways, assess the potential for adverse effects to aquatic organisms, and of identify spatial gradients in concentrations that may indicate potential point-sources metals. We also examined the role of natural sediment characteristics in metals concentration variability Study Area sediments were generally enriched in barium, cadmium, chromium, copper, lead, manganese, mercury, silver selenium, and zinc relative to the reference area. Compared to available sediment quality benchmarks, the only metals in the Study A rea presently at average concentrations sufficiently high to warrant concern about potential aquatic toxicity are lead, mercury, and zinc. Compared to the rest of the NY/NJ Harbor Estuary, the Study Area generally contains elevated levels of lead, manganese, silver and zinc. Variability in metals concentrations can not be accounted for by TOC or percent fines. However, a substantial proportion of the spatial variability in a number of metals can be explained by normalization to either aluminum or iron.