Analysis and Fate of Single-Walled Carbon Nanotubes and Their Manufacturing Byproducts in Estuarine Sediments and Benthic OrganismsEPA Grant Number: R833859
Title: Analysis and Fate of Single-Walled Carbon Nanotubes and Their Manufacturing Byproducts in Estuarine Sediments and Benthic Organisms
Investigators: Ferguson, P. Lee , Chandler, G. Thomas
Institution: University of South Carolina at Columbia
EPA Project Officer: Hahn, Intaek
Project Period: July 1, 2008 through June 30, 2011
Project Amount: $399,628
RFA: Exploratory Research: Nanotechnology Research Grants Investigating Fate, Transport, Transformation, and Exposure of Engineered Nanomaterials: A Joint Research Solicitation - EPA, NSF, & DOE (2007) RFA Text | Recipients Lists
Research Category: Nanotechnology , Safer Chemicals
The general objectives of the proposed research are to:
- Develop and validate sensitive and selective analytical methods based on near-infrared fluorescence (NIRF) spectroscopy for assaying the fate and transport of single-walled carbon nanotubes in estuarine sediment, water, and fauna.
- Utilize the developed NIRF methods in parallel with radiotracer experiments (14C-SWNT) to determine the partitioning, biological uptake, and transformation of SWNT and their nanocarbon manufacturing byproducts in estuarine sediment microcosms under laboratory conditions.
Our research plan will build-on and extend past and present EPA-supported work in our laboratories on estuarine fate and effects of SWNT. Specifically, we will take advantage of our stock of well-characterized SWNT, 14C-SWNT to fully develop and validate a new trace-analytical method aimed at specific detection of SWNT in complex mixtures. This method takes advantage of the unique and intrinsic NIR fluorescence behavior of pristine SWNT materials. The 14C-SWNT radiotracer will be utilized to track recoveries and analytical yield during the sample preparation steps and to standardize NIRF-based quantitative analyses. We will test our newly developed NIRF methods using SWNT standard-addition experiments with relevant sediments collected from areas likely to receive SWNT-input through manufacture or use of these materials. We will then perform parallel experiments using both radiotracer and unlabeled SWNT and nanocarbon manufacturing byproducts aimed at tracking the disposition of these carbon nanomaterials (and potential transformation products) among sediment, porewater, and meiobenthic organisms in sediment-microcosms collected from a pristine salt marsh estuary.
The proposed work will result in the first specific analytical method designed to detect and quantify SWNT in complex environmental mixtures, and this will provide the scientific community and regulators with a powerful tool for assessing exposure and risk of these important carbon nanomaterials in the aquatic environment. In addition, the novel combination of NIRF SWNT analysis with 14C-SWNT and 14C-labeled manufacturing byproduct radiotracer experiments in estuarine sediment microcosms will provide the first holistic picture of how these nanocarbons are transported, bioaccumulated, and potentially transformed in a complex and ecologically important environmental system. In total, our proposed work will provide novel tools and new data on dynamics of SWNT and their nanocarbon manufacturing byproducts in aquatic systems – data essential to future ecological and human risk assessment.