Wednesday, November 7, 2007 - 3:15 PM
321-11
Bioavailability, Toxicity and Trophic Transfer of Manufactured Nanoparticles.
Paul Bertsch1, T. Glenn2, N. Kabengi2, H. Ma3, P. Morris4, S. Murph2, A. Neal1, B. Neely4, Lee Newman5, J. Unrine2, and P. Williams3. (1) Department of Crop and Soil Sciences and Savannah River Ecology Lab, University of Georgia, P.O. Drawer E, Aiken, SC 29802-1030, (2) Savannah River Ecology Lab, University of Georgia, P.O. Drawer E, Aiken, SC 29802-1030, (3) Environmental Health Sciences, University of Georgia, Athens, GA 30602, (4) Marine and Biomedicine and Environmental Sciences Center, Medical University of South Carolina, Hollings Marine Laboratory, 331 Ft. Johnston Rd., Charleston, SC 29412, (5) University of South Carolina, Savannah River Ecology Lab, Drawer E, Aiken, SC 29802
It is widely acknowledged that we are at the dawn of a period involving major advances in technology spawned by new developments in the synthesis and application of nanoparticles and nanocomposites. The nanotechnology revolution offers great promise for major advances in numerous areas, including medicine, manufacturing, electronics, sensor development, energy production, pollution control, and environmental remediation, among others. Despite the benefits that will undoubtedly result from advances in nanotechnology, concerns surrounding the potential negative impacts to the environment and human health have emerged. We have been investigating the bioavailability and toxicity as well as the trophic transfer of ZnO and Au nanoparticles to microorganisms, detritivores, amphibians, and plants. Interdisciplinary studies include the characterization of the nanoparticles, the distribution of nanoparticles in biological tissues, nanoparticle toxicity as referenced to the free metal ion concentration, and gene expression associated with nanoparticle exposure. The results demonstrate the importance of characterization of nanoparticles under varying chemical conditions associated with exposure media and that nanoparticles are toxic to microorganisms and nematodes. The results also suggest a different spatial distribution in tissues as well as a unique toxicity mechanism compared to the free metal ion concentration. Ongoing studies are evaluating the propensity for nanoparticles to be transferred from one trophic level to the next by feeding pre-exposed microorganisms (B. vietnamensis) to the nematode, C. elegans and pre-exposed earthworms (E. fetida) to bullfrogs (R. catesbeiana) to test the hypothesis that surface modification of nanoparticles by peptides or other biomolecules facilitate the transmembrane transport of nanoparticles, thus enhancing the bioavailability to higher trophic levels.