Characterization of polycyclic aromatic hydrocarbon bioavailability in estuarine sediments using thin‐film extraction

Abstract

It is well documented that the bioavailability of hydrophobic organic chemicals (HOCs) can vary substantially among sediments. This makes risk assessments based on total sediment concentrations problematic. The present study investigates the application of thin-film solid-phase extraction to measure bioavailable concentrations of phenanthrene in estuarine sediment by comparing concentrations of phenanthrene in the amphipod Corophium colo and in thin ethylene/vinyl acetate films at different concentrations in three geochemically different sediments. For all sediment types, concentrations of phenanthrene in sediments and thin films followed linear relationships, indicating first-order exchange kinetics. Organism/thin-film concentration ratios did not vary systematically among sediment types but dropped significantly with increasing phenanthrene concentration in the sediments. While at low phenanthrene concentrations in the sediment fugacities of phenanthrene in the amphipods approached the fugacities in the thin films, they were significantly lower than those in the sediments at higher concentrations. While phenanthrene concentrations in the three sediment types were identical, biota sediment accumulation factors and concentrations in amphipods and thin films were consistently lower in sediments enriched with black carbon than in sediments with sedimentary organic matter bearing a more diagenetic organic signature. It is concluded that, for the range of concentrations tested, thin-film solid-phase extraction can be a useful tool in the characterization of differences in bioavailability of HOCs among sediment types.

A Perspective on the Toxicity of Petrogenic PAHs to Developing Fish Embryos Related to Environmental Chemistry

“…Shifts in PAH composition and the absence of dose-dependent relationships between particulate oil in water and eggs in oiled-rock column experiments demonstrate the successful adaptation of a procedure originally designed to study the chemistry of slightly soluble hydrocarbons to one that is useful for examining dissolved PAH toxicity without particulate oil as a confounding factor. These observations are consistent with independent contemporary studies of dissolved PAH toxicity (Rhodes et al 2005;Farwell et al 2006) and independent conclusions that dissolved PAHs are much more bioavailable and toxic than those adsorbed from whole oil (Neff et al 2005;Beckles et al 2007;Golding et al 2007). …”

“…Two other factors also have a major influence on effective concentration estimates. One concerns the presence or absence of particulate oil because dissolved PAHs are much more bioavailable and toxic than those adsorbed in whole oil (Neff et al 2005;Beckles et al 2007;Golding et al 2007;Carls et al 2008). The other relates to adverse embryo responses that require much longer periods of time to develop than commonly required for traditional short-term bioassays (e .g., 24 to 96 h).…”

Incorporating contaminant bioavailability into sediment quality assessment frameworks

“…Thus far, the silicone samplers have been applied solely in water‐only deployments (Booij et al 2002; Wenrich et al 2003; Rusina et al 2007; Yates et al 2007). Ethylene/vinyl acetate (EVA) has also been evaluated as a biomimetic PSD (Golding et al 2007, 2008; Tao et al 2008). In one approach to the design, EVA solution is applied to the interior of a vial and allowed to evaporate to a thickness of 0.05 µm (Golding et al 2008).…”

Ethylene vinyl acetate polymer as a tool for passive sampling monitoring of hydrophobic chemicals in the salmon farm industry

“…Ethylene vinyl acetate polymer (EVA) has been used as a sampler for several environmental compartments, such as air (Harner et al, 2003;Farrar et al, 2005;Wu et al, 2008), sediments (Golding et al, 2007;Meloche et al, 2009) and seawater (St George et al, 2011). EVA is a flexible polymer which can be easily processed and adapted to different substrates.…”