title: Predicting bioavailability of PAHs and PCBs with porewater concentrations measured by solid-phase microextraction fibers.
abstract: Bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was measured in the deposit-feeding oligochaete Ilyodrilus templetoni exposed for 28 d to Anacostia River sediment (Washington, DC, USA) and to an initially uncontaminated sediment from Brown Lake (Vicksburg, MS, USA) sequentially diluted with 3 to 25% contaminated New Bedford Harbor sediment (New Bedford, MA, USA). The Anacostia River sediment studies represented exposure to a historically contaminated sediment with limited availability, whereas exposure to the other sediment included both the historically contaminated New Bedford Harbor sediment and fresh redistribution of contaminants into the Brown Lake sediments. Organism tissue concentrations did not correlate with bulk sediment concentrations in the Anacostia River sediment but did correlate with the sequentially diluted sediment. Porewater concentrations measured via disposable solid-phase microextraction fiber (SPME) with polydimethylsiloxane (PDMS), however, correlated well with organism uptake in all sediments. Bioaccumulation was predicted well by a linear relationship with the product of porewater concentration and compound octanol-water partition coefficient (Anacostia, slope = 1.08, r² = 0.76; sequentially diluted sediments, slope = 1.24, r² = 0.76). The data demonstrate that the octanol-water partition coefficient is a good indicator of the lipid-water partition coefficient and that porewater concentrations provide a more reliable indicator of bioaccumulation in the organism than sediment concentrations, even when the route of uptake is expected to be via sediment ingestion.
authors.affiliation: Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, Texas, USA.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Lu
authors.forename: Alison
authors.initials: A
authors.lastname: Skwarski
authors.forename: Brian
authors.initials: B
authors.lastname: Drake
authors.forename: Danny D
authors.initials: DD
authors.lastname: Reible
mesh_terms: D000818:Animals; D005618:Fresh Water / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry; D009835:Oligochaeta / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D052617:Solid Phase Microextraction; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls