Chemometric comparisons of polychlorinated dibenzo-p-dioxin and dibenzofuran residues in surficial sediments from Newark Bay, New Jersey and other industrialized waterways

Abstract

The distributions of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) measured in surficial sediments from the lower Passaic River and Newark Bay, New Jersey were compared to those observed in sediments from other waterways located within industrial or heavily populated areas using chemometric techniques. Comparisons were conducted using published data to determine whether the distributions of 2,3,7,8-substituted isomers in surficial sediments from industrialized waterways have similar or different fingerprint patterns. Chemometric evaluations consisted of principal components analysis and the complete linkage: farthest neighbor cluster method. The concentrations of individual isomers were normalized to the combined sum of the 2,3,7,8-substituted PCDD and PCDF isomer concentrations in order to evaluate relative distribution patterns. Several of the isomeric fingerprint patterns found in sediments from the lower Passaic River and Newark Bay were similar to those found in sediments from New Bedford Harbor, MA, USA, Black Rock Harbor, CT, USA, Providence River, RI, USA, Eagle Harbor, WA, USA, the Inner Stockholm archipelago, Sweden, Hamburg Harbor, Germany, and St. Laurensharbor, The Netherlands. Pattern differences were observed in sediments from Frierfjorden, Norway, Niagara River, NY, USA, and Chemieharbor, The Netherlands. The variations among the 2,3,7,8-substituted isomer patterns observed in different sediments were largely explained by the distributions of the higher chlorinated isomers. Other differences may be attributed to environmental conditions unique to each waterway such as tidal flux, shipping traffic, urbanization, sedimentation rates, and the presence of different industrial sources. Similarities in PCDD and PCDF patterns among the waterways were related to the presence of similar municipal and industrial sources, including effluents from pentachlorophenol and polychlorinated biphenyl manufacturing facilities, pulp and paper mills, automobile and shipping traffic, and municipal solid waste and industrial incinerators. The distributions of PCDDs and PCDFs in surficial sediments from some areas of the Newark Bay estuary were representative of those found in many industrialized regions. It wsa evident from this analysis that the application of chemometric analysis can be useful in characterizing the distribution of complex multi-constituent chemical residues and identifying sources of these compounds in freshwater, estuarine, and marine sediments.