Metal evaluation, plant bioavailability

Element uptake from soil and transfer into the edible parts of plants have been addressed in several other studies. Soil-to-plant transfer factors in fruit and vegetables grown in various agricultural conditions have been determined for, for example, Pt [100], T1 [101], and various other metal contaminants [102], In a study on stable isotopes of fission product elements (Ce, Cs, Sr), an in vitro enzy-molysis method has been applied to investigate the solubilization of the analytes from fodder in a simulated ruminant digestion [103], The effect of inhibitors of fission product solubility was also considered and essential elements were determined simultaneously to evaluate potential nutrition problems for the animals from the use of such inhibitors. Selective leaching of individual classes of metal complexes with different ligands and sequential enzymolysis have been recently applied to estimate the potential bioavailability to humans of Cd and Pb in cocoa powder and related products [104]. 

Evaluation of the content of PGMs in airborne particles and dusts is important because of the possibility of their inhalation and accumulation in human lungs. Nanoparticles from autocatalysts can be transported into various parts of the environment (waters, plants, soils, and sediments) and transformed into more bioavailable species. There are data on the higher solubility of platinum from tunnel dusts than from inorganic species emitted from converters [30]. Distribution and accumulation of metals depend on traffic density, distance from the road, and meteorological conditions (wind, rain). The age of an autocatalyst and speed conditions directly affect the amount of nanoparticles released from catalytic... 

Plant Uptake In addition to metal bioavailability to humans, metal hioavailability to plants is an important parameter for evaluation of a remediation technology. Numerous studies have shown that P is effective in reducing Pb uptake by various plants. For example, P effectively reduced Pb uptake by tobacco from 36 mg kg to 16 mg kg (Mench, 1994). However, P was not effective in reducing Pb uptake by ryegrass in the same soil, although it was effective for other two soils where Pb uptake was reduced from 16.2 mg kg to 12.3 mg kg and from 4.9 mg kg to 1.4 mg kg . Laperche et al. (1996) showed that... 

The uptake of metals from agricultural soil by crops and vegetables is an important pathway through which metals in contaminated soils impose health threats to organisms. On the other hand, the capacity of plant roots to remove heavy metals from contaminated soils is an emerging environmental cleanup and remedial biotechnology. In order to evaluate the risks of metal contamination in the area, it is essential to understand metal bioavailability, which depends on a metal s chemical form in the soil, rather than on the total amount accumulated (Allen, 1997 Zemberyova etal, 1998). 

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