Testing of various membranes for use in a novel sediment porewater isolation chamber for infaunal invertebrate exposure to PCBs

Chemosphere. 2014 Jul;106:65-9. doi: 10.1016/j.chemosphere.2014.01.062. Epub 2014 Feb 26.

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.

Keywords: Benthic; Bioavailability; Diffusion; Membrane; Porewater; Sediment.

MeSH terms

  • Animals
  • Diffusion
  • Environmental Monitoring / instrumentation
  • Environmental Monitoring / methods
  • Environmental Restoration and Remediation
  • Geologic Sediments / chemistry
  • Hydrophobic and Hydrophilic Interactions
  • Invertebrates
  • Membranes, Artificial*
  • Plankton
  • Polychlorinated Biphenyls / analysis
  • Polychlorinated Biphenyls / chemistry*
  • Polychlorinated Biphenyls / isolation & purification
  • Toxicity Tests / instrumentation*
  • Toxicity Tests / methods
  • Water / chemistry
  • Water Pollutants, Chemical / analysis
  • Water Pollutants, Chemical / chemistry*
  • Water Pollutants, Chemical / isolation & purification

Substances

  • Membranes, Artificial
  • Water Pollutants, Chemical
  • Water
  • Polychlorinated Biphenyls