Effects of single-walled carbon nanotubes on the bioavailability of PCBs in field-contaminated sediments

Abstract

Adsorption of hydrophobic organic contaminants (HOCs) to black carbon is a well-studied phenomenon. One emerging class of engineered black carbon materials are single-walled carbon nanotubes (SWNTs). Little research has investigated the potential of SWNT to adsorb and sequester HOCs in complex environmental systems. This study addressed the capacity of SWNT, amended to polychlorinated biphenyl (PCB)-contaminated New Bedford Harbor (NBH) sediment, to reduce the toxicity and bioaccumulation of these HOCs to benthic organisms. Overall, SWNT amendments increased the survival of two benthic estuarine invertebrates, Americamysis bahia and Ampelisca abdita, and reduced the accumulation of PCBs to the benthic polychaete, Nereis virens. Reduction in PCB bioaccumulation by SWNT was independent of K_ow. Further, passive sampling-based estimates of interstitial water concentrations indicated that SWNT reduced PCB bioavailability. Results from this study suggest that SWNT are a good adsorbent for PCBs and might be useful for remediation in the future once SWNT manufacturing technology improves and costs decrease.

• Bioaccumulation
• bioavailability
• polychlorinated biphenyls
• single-walled carbon nanotubes
• toxicity

Acknowledgements

We thank Dr. Philip Wallis and SouthWest NanoTechnologies for the generous gifts of SWNT materials. Although the research described in this article was supported in part by the U.S. Environmental Protection Agency, it has not been subjected to Agency review and, therefore, does not necessarily reflect the view of the Agency; no official endorsement should be inferred.

Declaration of interest

The authors report no conflict of interest. The authors alone are responsible for the content and writing of this paper.

This work was supported by a grant from the U.S. Environmental Protection Agency to P. Lee Ferguson and G. Thomas Chandler (RD833859), and student services contracts (EP09D000098 and EP11D000011) from the U.S. Environmental Protection Agency to Ashley N. Parks.

Supplementary material available online

Supplementary Tables S1–S2

Supplementary Figures S1–S2