Uptake, localization, and speciation of cobalt in Triticum aestivum L. (wheat) and Lycopersicon esculentum M. (tomato).

The root-to-shoot transfer, localization, and chemical speciation of Co were investigated in a monocotyledon (Triticum aestivum L., wheat) and a dicotyledon (Lycopersicon esculentum M., tomato) plant species grown in nutrient solution at low (5 muM) and high (20 muM) Co(II) concentrations.

Potential phytoavailability of anthropogenic cobalt in soils as measured by isotope dilution techniques.

Isotope dilution is a useful technique to determine the potential phytoavailability of an element in soil. This method involves equilibrating an isotope with soil and then sampling the labile metal pool by analysis of the soil solution (E value) or plants growing in the soil (L value). The work reported here was conducted to evaluate the distribution coefficient (Kd), and the potential phytoavailability (E value) of cobalt (Co) in eight soils subjected to the atmospheric deposition of anthropogenic Co.

Assessment of isotope exchange methodology to determine the sorption coefficient and isotopically exchangeable concentration of selenium in soils and sediments.

Isotope exchange methodology is invaluable to determine the solution-solid-phase distribution (Kd) and isotopically exchangeable concentration (Evalue) of elements in soils and sediments. This work examined the use of species-specific stable isotope exchange techniques to determine the Kd and E value of selenium (Se), as selenite (SeO3) and selenate (SeO4), in nine soils and sediments varying in concentration and source of Se. High-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) was used to quantify the isotope (e.

Anion exchange liquid chromatography--inductively coupled plasma-mass spectrometry detection of the Co2+, Cu2+, Fe3+ and Ni2+ complexes of mugineic and deoxymugineic acid.

Phytosiderophores, such as mugineic and deoxymugineic acid, are produced by graminaceous plant species in response to Fe deficiency conditions normally experienced in calcareous and alkaline non-calcareous soils. As these phytosiderophores have the ability to form thermodynamically stable complexes with other metal cations present in the growing medium, they have also been implicated in the transport and bioavailability of these metals in the environment. However, routine analytical methodology to detect the various metal complexes formed by these phytosiderophores is lacking.

Performance of diffusion gradient in thin films to evaluate the toxic fraction of copper to Daphnia magna.

This study investigates the relevance of the diffusion gradient in thin films technique (DGT) to measure copper's induced lethality on Daphnia magna in natural water spiked with various organic ligands. Ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and glycine were used as artificial organic ligands in controlled solutions of mineral water. With EDTA, DGT measurement makes it possible to predict the toxicity of the mixture because Cu-EDTA complexes are inert, whereas DGT is of no help in the case of NTA, because Cu-NTA complexes are fully labile.