title: Equilibrium sampling of polychlorinated biphenyls in River Elbe sediments--Linking bioaccumulation in fish to sediment contamination.
abstract: Equilibrium sampling can be applied to measure freely dissolved concentrations (cfree) of hydrophobic organic chemicals (HOCs) that are considered effective concentrations for diffusive uptake and partitioning. It can also yield concentrations in lipids at thermodynamic equilibrium with the sediment (clip⇌sed) by multiplying concentrations in the equilibrium sampling polymer with lipid to polymer partition coefficients. We have applied silicone coated glass jars for equilibrium sampling of seven 'indicator' polychlorinated biphenyls (PCBs) in sediment samples from ten locations along the River Elbe to measure cfree of PCBs and their clip⇌sed. For three sites, we then related clip⇌sed to lipid-normalized PCB concentrations (cbio,lip) that were determined independently by the German Environmental Specimen Bank in common bream, a fish species living in close contact with the sediment: (1) In all cases, cbio,lip were below clip⇌sed, (2) there was proportionality between the two parameters with high R(2) values (0.92-1.00) and (3) the slopes of the linear regressions were very similar between the three stations (0.297; 0.327; 0.390). These results confirm the close link between PCB bioaccumulation and the thermodynamic potential of sediment-associated HOCs for partitioning into lipids. This novel approach gives clearer and more consistent results compared to conventional approaches that are based on total concentrations in sediment and biota-sediment accumulation factors. We propose to apply equilibrium sampling for determining bioavailability and bioaccumulation potential of HOCs, since this technique can provide a thermodynamic basis for the risk assessment and management of contaminated sediments.
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: sabine.schaefer@bafg.de.
authors: Sabine
authors: S
authors: Schäfer
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: catherine.antoni@mulewf.rlp.de.
authors: Catherine
authors: C
authors: Antoni
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: moehlenkamp@bafg.de.
authors: Christel
authors: C
authors: Möhlenkamp
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: claus@bafg.de.
authors: Evelyn
authors: E
authors: Claus
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: reifferscheid@bafg.de.
authors: Georg
authors: G
authors: Reifferscheid
authors: Department of Qualitative Hydrology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany. Electronic address: heininger@bafg.de.
authors: Peter
authors: P
authors: Heininger
authors: Department of Environmental Engineering, Technical University of Denmark, Kongens Lyngby, Denmark. Electronic address: philm@env.dtu.dk.
authors: Philipp
authors: P
authors: Mayer
mesh_terms: D000818:Animals; D058448:Biota; D004784:Environmental Monitoring / Q000379:methods*; D005399:Fishes / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry*; D050356:Lipid Metabolism; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls
keywords: Bioaccumulation; Equilibrium sampling; Freely dissolved concentration (c(free)); Polychlorinated biphenyl (PCB); River Elbe; Sediment