title: Testing of various membranes for use in a novel sediment porewater isolation chamber for infaunal invertebrate exposure to PCBs.
abstract: In benthic sediment bioassays, determining the relative contribution to exposure by contaminants in overlying water, porewater, and sediment particles is technically challenging. The purpose of the present study was to assess the potential for membranes to be utilized as a mechanism to allow freely dissolved hydrophobic organic contaminants into a pathway isolation exposure chamber (PIC) while excluding all sediment particles and dissolved organic carbon (DOC). This investigation was conducted in support of a larger effort to assess contaminant exposure pathways to benthos. While multiple passive samplers exist for estimating concentrations of contaminants in porewater such as those using solid-phase micro extraction (SPME) and polyoxymethylene (POM), techniques to effectively isolate whole organism exposure to porewater within a sediment system are not available. We tested the use of four membranes of different pore sizes (0.1-1.2μm) including nylon, polycarbonate, polyethylsulfone, and polytetrafluoroethylene with a hydrophilic coating. Exposures included both diffusion of radiolabeled and non-labeled contaminants across membranes from aqueous, sediment slurry, and whole sediment sources to assess and evaluate the best candidate membrane. Data generated from the present study was utilized to select the most suitable membrane for use in the larger bioavailability project which sought to assess the relevance of functional ecology in bioavailability of contaminated sediments at remediation sites. The polytetrafluoroethylene membrane was selected for use in the PIC, although exclusion of dissolved organic carbon was not achieved.
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA. Electronic address: jessica.g.coleman@us.army.mil.
authors.forename: Jessica G
authors.initials: JG
authors.lastname: Coleman
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Guilherme R
authors.initials: GR
authors.lastname: Lotufo
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Kennedy
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Aimee R
authors.initials: AR
authors.lastname: Poda
authors.affiliation: U.S. Army Engineer Research and Development Center, Geotechnical Structures Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Todd S
authors.initials: TS
authors.lastname: Rushing
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Ruiz
authors.affiliation: U.S. Army Engineer Research and Development Center, Environmental Laboratory, 3909 Halls Ferry Road, Vicksburg, MS 39180, USA.
authors.forename: Todd S
authors.initials: TS
authors.lastname: Bridges
mesh_terms: D000818:Animals; D004058:Diffusion; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods; D052918:Environmental Restoration and Remediation; D019015:Geologic Sediments / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D007448:Invertebrates; D008567:Membranes, Artificial; D010933:Plankton; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification; D018675:Toxicity Tests / Q000295:instrumentation* / Q000379:methods; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D008567:Membranes, Artificial; D014874:Water Pollutants, Chemical; D014867:Water; D011078:Polychlorinated Biphenyls
keywords: Benthic; Bioavailability; Diffusion; Membrane; Porewater; Sediment