Bioavailability of Lab-Contaminated and Native Polycyclic Aromatic Hydrocarbons to the Amphipod Corophium Volutator Relates to Chemical Desorption

Abstract

In the present study, the relationship between bioavailability of polycyclic aromatic hydrocarbons (PAHs) to benthic amphipods and the PAH desorption kinetics was examined. To that end, field-contaminated sediment was treated in three different ways. One subsample had no addition of PAHs and contained native PAHs only. To a second subsample, six PAHs (phenanthrene, fluoranthene, anthracene, pyrene, benzo[b]fluoranthene, and benzo[k]fluoranthene) were added in the laboratory. Two of the PAHs were added at higher concentrations to a third subsample, serving as a control for concentration-dependent uptake. Marine amphipods (Corophium volutator) were exposed to the three subsamples for a maximum of 25 d and were subsequently analyzed. Desorption kinetics were determined for both the lab-contaminated and the native PAHs. The biota-to-sediment accumulation factor (BSAF) values of the individual native and lab-contaminated PAHs correlated well with the rapidly desorbing fraction (R2 = 0.76). The BSAFs were 1.4 to 3.3 higher for the lab-contaminated PAHs compared with the native PAHs, while the difference between the rapidly desorbing fractions was a factor of 1.1 to 1.8. The BSAFs of the lab-contaminated PAHs in the second and third subsample were equal, indicating concentration-independent accumulation. The results suggest that lab-contaminated PAHs are more available to amphipods than native PAHs and that differences in bioavailability of lab-contaminated and native PAHs to marine amphipods are related to differences in desorption behavior.

Levels of polycyclic aromatic hydrocarbons and dibenzothiophenes in wetland sediments and aquatic insects in the oil sands area of Northeastern Alberta, Canada

“…PAH-BSAF values are not dependent on concentrations of PAHs in sediment (Kraaij et al 2001). Therefore it is unlikely that the lower BSAFs in experimental ponds were simply related to the higher PAH concentrations in sediments in those ponds.…”

“…Therefore it is unlikely that the lower BSAFs in experimental ponds were simply related to the higher PAH concentrations in sediments in those ponds. BSAFs are strongly influenced by sediment desorption kinetics (Lamoureux and Brownawell 1999;Kraaij et al 2001;Kukkonen et al 2004). In turn, sediment desorption kinetics are influenced by sediment characteristics.…”

Bioavailability of hydrophobic organic contaminants and quality of organic carbon

“…Simple fugacity models based on K oc (Karikhoff, 1981), and K oc with a black carbon term (Accardi-Dey and Gschwend, 2003) failed to accurately or consistently predict the total levels of PAHs or PCBs that were readily desorbed. Use of a functionally defined readily desorbed HOCs fraction (Kraaij, 2001) is a rapid means of obtaining sediment-specific information on the bioavailability of HOCs. Additional work is required to relate readily desorbed HOCs to body burdens in benthic infauna.…”

Uncertainties in Sediment Quality Weight-of-Evidence (WOE) Assessments

“…The reasons for this included the more realistic and environmentally variable conditions in the field, coupled with the impacts of differing levels of biological organization and larger spatial scales. Similarly, Kraaij et al (2001) concluded that increased toxicity to PAHs in the laboratory compared to the field was related to increased bioavailability of PAHs in laboratory toxicity tests. However, Long et al (2001) in a review of amphipod sediment toxicity test results and corresponding benthic infauna diversity and abundance, concluded that "ecologically relevant losses in the abundance and diversity of the benthic infauna frequently corresponded with reduced amphipod survival in the laboratory tests."…”