Table 2. Americium concentration ratios for plants grow in potted soils (from Plant Panel, 1976). — Range of CR's + Lime Plant Soil + Lime + DTPA and DTPA Conditions Rapporteur oF Pot culture Corn Soil pH = 6 10? 19? Soil il pH 10 “4 10 ° = 8.5] 8. Soil pH = 7.5; Soil pk = 6 10 ! |10? chelate applied to soil. 10° 10° Bush bean Sand texture Clay texture Corn Sand texture Clay texture 10! Wallace 10 107? — 10° - _ _ 10 _ 10' 10! 10 + 10? 10 10 ' 10? 10)1 10 chelate added 10° Adriano to Am stock 10° ~h tors Contaminated soil from NTS areas 11, 13; 3 kg pot. Alfalfa 10“ to 10? Am-sol'n added to . _ 10°° to io > In 3 kg NTS soil; 0.6 nCi g! soil; highest CR's involve chelate Soybean Forage Bean 0.01 lower \, Barley 0.02 to 0.01 lower | Condition ~~ Rapporteur Pot culture Romney Pot culture Schulz 0.01 to 0.001 lower Pot culture Wildung Field lysimeter Cline Garden plot Dahlman Field crop Adriano Peas 2 Ci en's 107 to 10° Grain 0.01 to 9.001 lower Barley Soybean Wheat grain Barley Straw Seed-fruit CR's relative to leaf-stem Barley Barley cea Plant Soybean 10! 107! - Difference factors of Pu concentration ratio for leaf-stem versus seed-fruit (from Plant Panel, 1976). 10 net g7}; - Bush bean Soil pH = 7 In addition to gross uptake and translocation of plutonium, the relative concentration in fruit versus vegetation was examined by the Panel (Table 3). From the various data presented, it appeared that the fruits tended to be much lower in plutonium than the foliage, with the range of relative concentration of plutonium in the fruit being 0.5 to 0.001 of that of the plant foliage. Table 3. Barley - Upon inspection of the rather limited comparative data presented, it appeared to the Panel that americium is taken up by plants about 100 to 1000 times more readily than is plutonium. Also, the data indicate that the presence of complexing agents such as chelates could well influence plant root uptake and translocation of both plutonium and americium. Barley 0.01 lower Cheatgrasa Bush bean 0.1 lower | Millet 0.5 lower | Wheat 0.1 lower ? Schulz INFLUENCE OF SOURCE CHARACTERISTICS soils; 3 kg pot 7 10 * to 103 A group of investigators (Adams et al., 1975) studied uptake of plutonium from ?3®Pu0, microspheres. The microspheres were 100 Um particles, which treatment. - s Romney 10°? to 10! In 3 kg NTS soil; 5 nCi 10" to 10 ? are in the fine sand range and have relatively little surface area. The plutonium concentration ratios found in this study were in the order of 107? to 10-7. These concentration ratios were based on plant ash weight and therefore would be about a factor of 10 lower if based on the more usual dry plant weight. This group of investigators also found that g ' soil; highest CR's involved chelate treatment. } es 324 325