title: Bioavailability of polycyclic aromatic hydrocarbons in field-contaminated Anacostia River (Washington, DC) sediment.
abstract: Sediment-water partitioning behavior and bioavailability of five polycyclic aromatic hydrocarbons (PAHs; phenanthrene, pyrene, chrysene, benzo[k]fluoranthene, and benzo[a]pyrene) were measured in field-contaminated sediment collected from moderately polluted regions of the Anacostia River (Washington, DC, U.S.A.). Much of the sediment PAH burden was resistant to desorption: Effective partition coefficients were 2- to 10-fold greater than expected from literature values, and more than 80% of PAHs remained sorbed after treatment of the sediment with a nonionic polymeric adsorbent (Amberlite XAD-2) for 20 h. Bioaccumulation, elimination, and assimilation of each PAH in the deposit-feeding tubificid oligochaete Ilyodrilus templetoni were measured and compared with the equivalent measurements from laboratory-inoculated sediment. Ilyodrilus templetoni effectively accessed the desorption-resistant fraction of these organic contaminants, as exhibited by high single-gut passage assimilation efficiencies (ASEs) of the five PAHs (60% < ASE < 90%). However, steady-state accumulations of PAHs by I. templetoni were very low and consistent with low pore-water concentrations. The present results suggest that steady-state accumulation of PAHs is controlled by pore-water concentrations and is not necessarily related to route of uptake or assimilation efficiencies.
authors.affiliation: Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Lu
authors.forename: Danny D
authors.initials: DD
authors.lastname: Reible
authors.forename: John W
authors.initials: JW
authors.lastname: Fleeger
mesh_terms: D000327:Adsorption; D000818:Animals; D001682:Biological Availability; D004219:District of Columbia; D019015:Geologic Sediments / Q000737:chemistry*; D009835:Oligochaeta / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D016062:Porosity; D045483:Rivers; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical