Abstract Details
| Lead Nanoparticles in the Aquatic Fern Salvinia minima L. Baker | |
|---|---|
| Abstract ID | ENV-03 |
| Presenter | Jennifer Cassano |
| Presentation Type | Poster |
| Full Author List | J. A. Cassano (1) , C. Patty (2) , J. Santamaria (3) , D. L. LeDuc (1) , J. C. Andrews (2) |
| Affiliations | (1) Department of Chemistry and Biochemistry, California State University, East Bay, Hayward, CA 94542 (2) Stanford Synchrotron Radiation Laboratory, 2575 Sand Hill Road, MS 99, Menlo Park, CA 94025 (3) Biotechnology Department, Centro de Investigación Científica de Yucatán, Mérida ,Yucatán, México |
| Category | Environmental Science |
| Abstract | Lead (Pb) is a potent toxin that
can gradually accumulate in the body and damage the central nervous system.
Because of its commercial importance, human activities have dispersed Pb
throughout the biosphere. Once Pb enters the aquatic ecosystem, it bioaccumulates up the food chain, posing serious health
risks to people and wildlife. Public concern over lead exposure has sparked an
interest in the remediation of lead-affected sites.
Phytoremediation, the use of plants to clean up environmental toxins, is a promising technique for the remediation of many heavy metals and metalloids. This approach depends on plants able to accumulate and/or tolerate high concentrations of the metal, which, in the case of Pb, are notably rare. The aquatic fern, Salvinia minima L. Baker, however, is one such plant. S. minima can accumulate up to 10.62 mg Pb/g dry weight, tolerate a wide range of temperatures, is highly productive, and grows copiously. The underlying mechanism responsible for S. minima’s ability to take up, tolerate, and accumulate Pb remains unknown. As one approach towards elucidating this mechanism, we used Transmission X-ray Microscopy (TXM) and X-ray Microprobe to learn more about the distribution of Pb and other metals within S. minima. TXM, with 40 nm resolution, revealed the presence of dense metal clusters approximately 3 microns in diameter, containing nanoparticles 0.2-0.5 microns in size. X-ray microprobe, at 0.5 micron resolution, located a hot spot of Pb approximately 3 microns in diameter, and other low-level Pb distributed throughout the leaf. The Pb hot spot was seen to co-localize with Fe and possibly Mn, but not with Ca, Cu or Zn. This opens the possibility that at least some of the Pb accumulated by S. minima is present in a mineralized form. |
| Footnotes | |
| Funding Acknowledgement | This project was supported by CSUEB start-up funding to D.L.L. |