Phytoavailability and toxicity of beryllium and vanadium

Abstract

Greenhouse and laboratory studies were conducted to evaluate the toxic effects of Be and V on collards (Brassica oleracea, var. acephala L.). In the laboratory germination study, incremental increases in the Be concentrations of the growing medium induced a steady decline in the radicle length of seven-day-old collard seedling. Beryllium concentrations greater than or equal to 8 mg Be L -1 totally inhibited seed germination. The presence of V in the growing medium had no effect on collard germination; however, it had a profound effect on subsequent radicle elongation. Concentrations of V less than 1 mg V L 1 stimulated radicle elongation, while concentrations greater than or equal to 3 mg V L ~, caused severe toxicity. In the greenhouse study, Be toxicity was observed in collards grown in a Blanton sand (Grossarenic Paleudult) received treatments greater than or equal to 150 mg Be kg -1 (as BeSO4). Irrespective of treatment level, 97% of the Be taken up by the plants remained in the roots while only 3% was translocated to aboveground plant parts. Vanadium tissue concentraltions and toxicity to collards varied with soil type. Additions as low as 80 mg V kg -1 to the Blanton sand significantly reduced collard biomass while additions as high as 100 mg V kg 1 to an Orangebury loamy sand (Typic Paleudult) had no effect on plant biomass. The differential response was attributed to greater accumulation of V by plants grown in the Blanton soil.

Some Responses of TwoNicotiana tabacumL. Cultivars Exposed to Vanadium

“…'Burley' and N. tabacum cv. 'Virginia' agrees with other authors' results for different species (Kaplan et al, 1990;Wang et al, 2008;Olness et al, 2005;Potters et al, 2007). The increased thickness and shorter length of the roots are symptoms of vanadium toxicity (Morrell et al, 1986;Martín and Saco, 1995;Potters et al, 2007); this decrease in root growth may be due to an increase in wall lignification as a defence mechanism (Halusková et al, 2010).…”

“…It could also be a growth strategy used by certain species when subjected to high concentrations of heavy metals (Ekmekçi et al, 2008;Gallagher et al, 2008;Rascio and Navari-Izzo, 2011). The relationships between root vanadium content and the supply of this element in the growth medium have also been studied by other authors (Kaplan et al, 1990;Fargasová, 1998;Morrell et al, 1986;Vwioko et al, 2006).…”

Subcellular distribution and translocation of radionuclides in plants

“…For V, Y, Be, Se, Nb, Sc, Cr, and Zr, most of the activity was retained in the roots with little transport to the shoot, indicating either their immobility or lower demand by developing tissues. Retention in the root and nontranslocation to aerial parts was reported for Be, V [13], and Cr [14,15].…”

Vanadium bioavailability in soils amended with blast furnace slag

“…Vanadium is often strongly retained in soils [10][11][12][13], and metal (hydr)oxides are important for vanadium sorption [14,15]. The retention of vanadium in soils is most pronounced around pH 4 [11].…”