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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.

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evaluated as sequestering agents for environmental cleanup (Ming and Mumpton, 1995;Tsitsishvili et al., 1992). Laboratory and greenhouse studies were conducted to quantifyThe goal of in situ immobilization is to reduce the apatite and phillipsite (zeolite) sequestration of selected metal conrisk associated with potentially bioavailable toxic mettaminants. The laboratory batch study measured the sorption of aqueals. However, an important limitation of this approach is ous Co 2؉ , Ba 2؉ , Pb 2؉ , Eu 3؉ , and UO 2 2؉ . Apatite sorbed more Co 2؉ , Pb 2؉ , Eu 3؉ , and UO 2 2؉ from the spike solution than phillipsite, resulting

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