208 THE SHORTER-TERM BIOLOGICAL HAZARDS OF A FALLOUT FIRLD CONTAMINATION OF PLANTS, ANIMALS, SOIL, AND WATER Tasit 4~-AVERAGE RELATIVE COMPOSITION OF NUCLIDES IN PLANTS, SOIL, AND WATER Namber of Soures Plant: Portulaca. .....2.--- Papaya... 2 ee saniples averaged Port --Whole__- Plants -- Pandanus.....-.22.-.2--- 20 eee eee Leaves__. Air root... . Tuber... AMtOW TO0t wn nnenee serene eee ees Depth, Q-1 im. ... 22-220. nee eee eee Source: Cistern...--- 2... 6-22 eee eee eee Well... Cyst 1 7%. 8 98, 2 2 1 2 90. 5 99. 6 83 2 2 2 1 Solt Water 48.9 I 3 2 JOCONUE. ne Shell. oe 1 98.9 92. 6 72.7 88.9 75.4 1.7 34 2 2 2 2 we Total rare earths Brie Of the plant samples examined, portulaca had the highest sunshine units; values were 6,140 and 25,000 for the two specimens analyzed. In coconuts the activity of teat, shell and milk was not statistically significant, whereas the value for husks ranged from 1,200 to 4,000. a ee Rute also fell within this range. Arrowroot leaves, stalks and tubers were significantly lower, ranging from &6 to 780 sunshine units. 17.8 V1 05 water samples; however 4 samples showed some The sunshine units in the 0 to 1 inch layer of 4 2 86.5 2.2 13.3 10.3 16.8 activity with sunshine units between 150 to 200. A saniple of cistern water from Rongelap, the notable exception, had a value of 10,000. Noteworthy is the fact that the activity in portulaca, coeoput husks, pandanus keys and air roots, as well as a sample of potable water, execeded the maximum tolerance level of Sr, Tasue §~SUNSHINE UNITS OF PLANT, WATER AND SCIL SAMPLES samp! 83. 9 83. 8 soil on 5 islands were 17 to 92; the exception, Gejen, had a value of 7,000. Strontium-90 was not detectable in most Pandanus keys and pandanus air root values 39, 2 “ample 5.6 SOMLS Istana oe Calcium in kg of Soil (g) 10.0 64.4 100 94.5 100 + Rongelap-. Gejen_- Depth (Q-1 in.) --------++-- tures in the coconut palm and the errowroot plant differed markedly from the respective nut and tuber. These structures accumulated the rare earth isotopes in exceedingly greater concentration than Cs", Table 4 shows further that plant leaves contained varying percentages of Ru’ and that the concentration of this isotope represented only a small fraction of the total activity. In portulaca, a widely distributed plant, the nuclide composition was 49, 39 and 12 percent Cs", rare earths, and Sr™, respectively. Despite the inaclivity of the water samples, rare earth and Srdeterminations were per‘formed since self-absorption as well as the size of aliquot used may have obscured theactivity. 3.35 1064138 x10 5.26 x 1084 5.2 x 10 21x 10422 x 108 360 268 5.8 x 104423 x 10° 48x 10443.0 5 10 Cs" and Ru'* were not determined because 13 x 104E 1.0 x 108 4742 7x 107+ 70 243 11 733 9246 WATER self-absorption does not play an important role in the detection of these gamma-emitters. The Calcium in Liter (mg) results of these analyses are shown in Table 4. With the exception of a sample of cistern water which had ® significant quantity of Sr®, the observed activity was attributable to the rare earths, With regard to soil, the average of two com- Cistern. -.--~------------~- (Rene oe cent Ru’, 5 percent Sr® and less than 1 percent Cs, Where comparisons were available, the relationships among nuclides in the current Lagoon... 222-2 ene ee ee Eniwetak . Rongelap.-.... Well... 0-20 e ee ene Utirik.. Utirik. . Eniaetok. ... Rongelap.... Ocean. .- 0-222 -2-e ween ee Utirik... Eniwetak plete assays gave 84 percent rare earths, 10 per- Rongelap. Utirik.. 22.2. survey in genera] agreed with those previously reported [3]. The only sharp difference was the NDAindicates no detectable activity. higher percentage of Cs” in the one papaya analyzed in the present study. The sunshine units are recorded in Table 5 for the plant, water and soil samples analyzed. }- arrowroot tubers and only a small fraction from (adisrecs) 2 dim Seis Sree (d/nfke) 316 B41 352 350 Utirik._..-.. coconuts and pandanus keys. The Sr® concentration in these specimens was uniformly low. The nuclide composition of the leafy struc- 209 48 1180-410 88 80 2300 39-10 NDA NDA 61 -- Srtt (d/mifliter) 352 408 402 20-414 NDA NDA NDA A456 190-68 Ad] 204 + 150 137 NDA 1.1 x 1044230 147-£ 104 201454 188; 68 0 0 9 0 0 9 208-+ 150