PCB Congeners and Dechlorination in Sediments of Sheboygan River, Wisconsin, Determined by Matrix Factorization

Abstract

Nine sediment cores were collected from the Sheboygan River Inner Harbor, WI, and analyzed for polychlorinated biphenyl (PCB) congeners. Total PCBs ranged from approximately 0 to 161 mg/g. Positive matrix factorization (PMF) was applied to the PCB data setto determine source profiles. Two factors were determined to be significant. One factor resembled the original approximated PCB mixture of 50% Aroclor 1248 and 50% Aroclor 1254 and the other factor was a dechlorinated version of the mixture. An anaerobic dechlorination model was applied to the dechlorinated source profiles to quantify possible dechlorination pathways. It was found that dechlorination process H' provided the best fit for an individual process, and H' + M provides the best fit for combined processes. PMF source contributions, and plots of PCB concentration versus congener for individual samples, provide evidence of enhanced dechlorination at high concentrations (>40 ppm) and small amounts of dechlorination at low concentrations (<3 ppm). In addition, downward migration of lower chlorinated PCBs in core SR1a has occurred. Remediation dredging in the Upper Sheboygan River in 1989 and 1990 reintroduced PCBs to the water column and selective transport of PCB 18 is observed in core SR7.

Polychlorinated biphenyls in two salt marsh sediments of the Venice Lagoon

“…2), with the progressive increase of heavier congener abundances, especially the 6Cl homologues CB-153 and CB-138. Though the trend is not regular, some hypotheses could be advanced on the role of degradation: in general, lower chlorinated PCBs tend to be more readily biotransformed under aerobic conditions, whereas the highly chlorinated congeners are preferentially dechlorinated in subsurface sediments by anaerobic reductive processes (Brown et al 1987;Quensen et al 1988;Bedard and May 1996;Bzdusek et al 2006). In the two marsh cores, we observe an irregular decrease of the presence not only of 3Cl and 4Cl congeners (CB-28 and CB-52) but also of 5Cl and higher chlorinated PCBs (CB-101, CB-118 and CB-180 in some cases).…”

Changes in polychlorinated biphenyl (PCB) exposure in tree swallows (Tachycineta bicolor) nesting along the Sheboygan River, WI, USA

“…Management actions for this AOC are summarized by Shrank et al (1997). It is believed that the PCBs came from an industrial site in Sheboygan Falls that used hydraulic fluids containing PCBs (Bzdusek et al 2006), whereas the PAHs originated from highway dust, gasification plants, and coke oven emissions (Lu et al 2005). One of several beneficial use impairments (BUIs) identified as part of the AOC process was possible adverse effects of contaminants on avian reproduction.…”

Nationwide PCB congener pattern analysis in freshwater fish samples in France

“…Moreover the negative eigenvectors sometimes obtained in PCA are not appropriate when looking for source profiles. While there are numerous examples of pattern analysis using models adapted from multivariate statistics in environmental matrices such as air (Logue et al, 2009;Pekney et al, 2006), soil (Skrbic and Durisic-Mladenovic, 2007) or bottom sediment (Bzdusek et al, 2006a;Bzdusek et al, 2006b;Du et al, 2008), there have been fewer attempts to develop this kind of approach on biota. Examples include an exploration of spatial differences in organochlorine chemical loads in herring gull colonies of the Great Lakes (MacDonald et al, 1992), a study of PCB accumulation features, but neither spatial nor source pattern analysis in the Baltic Sea area (Falandysz et al, 2002), an attempt to differentiate local PCB sources in the Hudson River and its estuary Monosson et al, 2003), and a study of PCB pattern variations across species, trophic levels, and wild versus farmed salmon (Yunker et al, 2011).…”