2, No. 2, 1959) LAUG AND WALLACE! RADIOACTIVE RESIDUES IN FOODS on ash samples ard, counts per 1 to disintegra-~ olying c/m by . for potassium iracy of 5%. m of original ittegrations per by 1.776. This data published 433 Table 1. Average total beta radioactivity of fruits and fruit products harvested before and after 1945 No. Before 1945 d/m/g Pears Cherries Peaches 36 44 51 0.01 0.00 0.00 Apples? 19 Fruit Apricots Prunes and plums No. 0.033 0,042 0.040 12 17 38 0.00 0.16 0.04 0.032 9 6.00 0.22 0.089 40 0.24 0.054 21 0.00 0.071 0.047 21 0.03 0.0854 83 36 60 Fruit juices, other? 29 17 0.10 0.01 0.01 0.04 0.047 0.054 0.041 0.06 0.056 0.00 5 0.00 0.056 0.037 0.053 11 Tomatoes¢ Miscellaneous? Berries* Citric fruit juices’ From 1945 to 1957 incl. d/m/g s.e.() 8.e.(+) 51 21 13 0.00 0.00 0.00 11 0.00 0.111 0.073 0.051 0.080 0.084 0.046 @ Exelusive of dried fruits, ' Includes apple sauce. ting from the ion due to the verage the net in those cases ices or fission ver the term een used suborrected value oeriments with a radioactivity ‘Ing weights of tass absorption 5%. However, also exhibited xr, these errors Hence with orrections for the probable rardiess of the is number, is his low order © Includes juices, relishes, catsup, soup. 4 * f * Includes Includes Includes Includes grapes, pineapple, rhubarb, currants, pumpkins, quinces, figs, olives, nectarines, but no citrus fruits. predominantly strawberries, raspberries, and blackberries, lemon, lime, grapefruit, and orange. predominantly grape and apple, Sensitivity The counting equipment was capable of detecting one count per minute total beta radioactivity above background in a 100 mg sample of ash. Depending on the ash content, this represents from 0.02 to 0.5 ¢/m in terms of the original food. Table I gives the results for fruits and fruit products. No significant increase in radioactivity of the post-1945 over the pre1945 samples is demonstrated. Reference to the raw data from which these averages were constructed shows that a predominant number of samples originated in the years 1945 to 1950, inclusive. During this period nuclear weapons testing with resultant fallout had not yet reached the proportions that followed im later years. It might be assumed therefore collected in 1945 the average was 0.05 d/m/g the average was 0.00 d/m/g. No significant increase in radioactivity by year could therefor be demonstrated. Since only a very small number of dried fruit samples were available for analysis, no significant comparisons between pre- and post-1945 periods could be made. There is some indication, however, that a trend toward increased radioactivity in current samples of dried fruits may be occurring. Table 2 gives the results for vegetables. Nosignificant increase in radicactivity of the before and after 1945 Vegetable at as = 20%. n measuring determinable, significantly Potatoes Corn Beans? Peas lvtical opera- Spinach? e determinaradioactivity. y be additive ossible. lected in 1945 with the average of all samples collected in 1956 and 1957. For 78 samples Table 2. Average total beta radioactivity of vegetables harvested tause most of tive content. 1 1:1 to 4:1, ble error was Accordingly, the data were analyzed by comparing the average of all samples col- and for 44 samples collected in 1956 and 1957 Results otal count to Such a favor- that the conclusions indicated from Table 1 should be subject to revision. Beets and turnips Carrots Miscellaneous¢ No. Before 1945 d/m/z 20 43 79 35 0.13 0.00 0.00 0.00 21 0.00 54 0.00 28 10 0.00 0.01 g.e.(+) No, 0.185 0.062 0.043 0.064 0.093 0.113 0.125 0.050 9 AT 53 57 12 19 17 25 From 1945 to 1957 incl. d/m/g s.e.(+ 0.00 0.01 0.05 0.06 0.03 0.06 0.00 0.11 0.192 0.047 0.096 0.042 0,104 0.116 0.119 0.080 @ Includes lima, soy, etc. * Three samples, only, from year 1956 showed an average value of 0.30 d/m/g. ¢ Fncludes asparagus, Mustard greens, onioDs, pimentos, okra, mushrooms, squash, cabbage, broccoli, catfower.