| Popis: |
Cabbage, potatoes, soybeans. and wheat were analyzed for Sr90 in nine U.S. cities during 1959 and 1960. The Sr90 found to be about three times that of cabbage, potatoes, or soybeans, whereas in terms of Sr90/unit- wet-weight soybeans have the highest concentration. The decline in Sr90 concentrations in some staple cereals and vegetables was not as great as in milk, indicating that foliar uptake is a smaller factor in these crops. The decline in milk concentrations of Sr90 in the U.S. is reflected in lower concentration in fetal bone. It is believed that is possible that rainfall, irrespective of its Sr90 content, may be an important factor in the uptake of the radioisotope in some plants. |
