Sensing Dissolved Sediment Porewater Concentrations of Persistent and Bioaccumulative Pollutants Using Disposable Solid-Phase Microextraction Fibers

Abstract

Polymer coated glass fibers were applied as disposable samplers to measure dissolved concentrations of persistent and bioaccumulative pollutants (PBPs) in sediment porewater. The method is called matrix solid-phase microextraction (matrix-SPME), because it utilizes the entire sediment matrix as a reservoir for an equilibrium extraction: a glass fiber with a 15 μm coating of poly(dimethylsiloxane) (PDMS) was placed in a sediment sample until the PBPs reached their equilibrium distribution between the PDMS and the sediment matrix (1−30 days). PBP concentrations in the PDMS were determined by gas chromatography, and they were divided by PDMS water partition coefficients to derive at dissolved porewater concentrations. This approach was applied to measure porewater concentrations of spiked as well as field sediment, and several hydrophobic organic substances (log K OW 5.2−7.5) were measured with high precision in the pg to ng/L range. Simple equilibrium partitioning is the basis for the substantial concentration factors that are built into matrix-SPME and for the low demands in materials and operation time. Matrix-SPME was in this study directed at the determination of dissolved porewater concentrations in sediment, and it is further expected to be applicable to other environmental media, to field sampling, and to the sensing of fugacity.

Addition of contaminant bioavailability and species susceptibility to a sediment toxicity assessment: Application in an urban stream in China

“…As an activity-based measurement, matrix-SPME measured the freely-dissolved CUP concentrations (Mayer et al, 2000;Cui et al, 2013). Ten cm of disposable SPME fibers coated with 10 mm polydimethylsiloxane were protected in a stainless envelope with 110 mm openings.…”

“…Chemical extraction techniques, such as Tenax extraction and matrix-solid phase microextraction (matrix-SPME), have been developed to measure the bioavailability of sediment-associated contaminants (Cornelissen et al, 1997;Mayer et al, 2000;Reichenberg and Mayer, 2006). Bioavailable concentrations measured by desorption-based Tenax extraction better explained sediment toxicity of pyrethroid-contaminated sediments in the field compared to OC-normalized concentrations .…”

Sorption of PBDE in low‐density polyethylene film: Implications for bioavailability of BDE‐209

“…Polymer-coated (such as poly(dimethyl)siloxane [PDMS]) glass fibers [10] and low-density polyethylene (LDPE) films [11] have been used as biomimic probes, because they behave similarly to biological lipid. In such applications, the key step is to accurately determine the partition coefficients between the sorbent phase and water.…”

Bioavailability of Hydrophobic Organic Contaminants in Sediment with Different Particle-Size Distributions

“…Sediment porewater concentration (C pw ) was calculated by dividing fiber concentration (C f ) by the partition coefficient between the fiber and the water (K fw ), which was calculated using the relationship between K fw and K ow (log K fw = log K ow -0.91) (Mayer et al 2000) as follows (Eq. 6):…”