You are here:
IN-VIVO SYNCHROTRON ANALYSIS OF THALLIUM IN IBERIS INTERMEDIA
Citation:
Scheckel*, K G., S A. Rock*, E. Lombi, AND M. McLaughlin. IN-VIVO SYNCHROTRON ANALYSIS OF THALLIUM IN IBERIS INTERMEDIA. To be Presented at Soil Science Society of America Annual Meeting, Seattle, WA, October 31 - November 04, 2004.
Impact/Purpose:
to present information
Description:
Thallium (TI) is a metal of great toxicological concern and its prevalence in the natural environment has steadily increased as a result of manufacturing and combustion practices. Due to its low natural abundance and the increasing demand, TI is the fourth most expensive metal, thus, recovery and reuse could be a profitable endeavor. The hyperaccumulator, Iberis intermedia, was examined via in-vivo micro-X-ray absorption near edge (micro-XANES) and micro-X-ray fluorescence (micro-XRF) spectroscopies to determine the speciation and distribution of TI within leaves of the plant. I. intermedia plants were cultivated under controlled conditions in 0, 10, and 20 mg TI kg-l soil leading to a shoot concentration of up to 13 430 mg TI kg-l dry weight plant mass during 10 weeks of growth. Live plant leaves were examined by micro-XANES and micro-XRF which determined aqueous TI(I) to be the species distributed primarily throughout the vascular network. A direct relationship of vein size to TI concentration was observed. The high uptake of TI and high potential biomass of I. intermedia , combined with knowledge of TI speciation and compartmentation within the plant, are discussed in terms of accumulation/tolerance mechanisms, consequences for potential food chain contamination and phytomining strategies to reclaim Tl-contaminated soils, sediments, and waters.