Plant uptake of /sup 237/Np, /sup 239/ /sup 240/Pu, /sup 241/Am, and /sup 244/Cm from soils representing major food production areas of the United States

Crops of peas, soybeans, tomatoes, and wheat were grown in seven different soils uniformly contaminated with mixtures of /sup 237/Np, /sup 239/ /sup 240/Pu, /sup 241/Am, and /sup 244/Cm. The plant uptake experiments were performed in 200-liter containers, to simulate field conditions. Crop yields varied with the fertility conditions of the soils. Differences in soil properties were a major cause of variability in the concentration ratios (CR) that measure the transuranic element uptake by food crop plants through root systems. Root uptake of /sup 239/ /sup 240/Pu was lowest, with CR values for vegetative parts of plants ranging from 10/sup -6/ to 10/sup -4/. The CR values for /sup 241/Am and /sup 244/Cm were essentially the same, ranging from 10/sup -5/ to 10/sup -2/. The CR values for /sup 237/Np in vegetative parts ranged from 10/sup -4/ to 10/sup -1/. The CR values for seed, grain, and fruit parts of plants generally were a factor of 10 lower than values for foliage.