ranged from 0 to 570 (dis/min)/liter. dis/min per gram wet weight. Unsorted zooplankton ranged from 3 to 140 Radiochemical analysis of the plankton showed 80 to 90 percentof the activity to be Ce! and Prwith some Sr™ present (Reference 4). 1.3 THEORY The state of a mixture of fission products changes following entrance into the ocean. tion in the studies of fallout patterns in a given area. Studies of the predominant chemical species resulting from an underwater burst of an atomic device indicate that some of the long-lived fission products should be soluble in sea water, while others should be insoluble. Table 1.1 gives the chemical species and physica] state of those elements which may be present 2 years after an atomic explosion (References 5 and 6). TABLE 1.1 Element sity a Physical and biological separations then begin to occur producing depletions in one phase and concentrations in others. Such occurrences should be taken into considera- ESTIMATED PREDOMINANT REACTION PRODUCTS OF LONG LIFE ISOTOPES IN SEA WATER TWO YEARS AFTER A NUCLEAR EXPLOSION Predominant Half Life Reaction Products Predominant Physical State Contribution to Total Fission Product Activity pet CeO, Pr,Oy; Pm,03, Pm,0; + xH,O Solid Solid Solid Y;03, Y,0,* xH,O Solid yy” 64 hours 28 years Sr*? cst 33 years Cst Ba?m Ru’ 2.6 minutes 1.0 years Rhi* 30 seconds Nb’S zr Eu'# Sm!! 35 days 65 days 1.7 years 73 years Kr*5 Sb'#5 zn® 10.6 years 2.7 years 245 days RuQ,, (Ru, Ru,O; * xH,0) Rh,O;, Rh,Q; - xH,O (Rh) Kr Nb,Os, Nb,O, - xH,O ZrOQ;, ZrO, - xH,O Eu,03, Eu,0; - xH,O Sm,0y Sb,0,, (Sb,0,) ZnO, Zn(OH); 270 days Co(OH), Mn 290 days Mns0, (Mn *?) Co Ionic Ba*? Co™ ' §.2 years Ionic 6.3 6.3 4.0 Ionic 3.6 Solid 3.3 Solid Solid Solid Solid 0.8 0.4 0.2 0.2 Solid Gas, dissolved Solid Solid Co(OH), 27 27 15 3.3 1.0 0.15 _— Solid — Solid, ionic — Solid Oe ee ey am ek sr” 282 days 17 minutes 2.6 years —_— sateen ee 3 ae Ot te os Ce pri Pm‘? As shown in Table 1.1, cesium and strontium, which are soluble in sea water, are mg/liter. . The addition of 1 yc of cesium per liter would add 12.5 x 10~® mgto the potassium. One ue of radiostrontium per liter would increase the strontium content by 7.3 x 1078 mg. In addition, strontium is similar to calcium and is so used by organisms. — 14 How- whgribe «4. Steer + OE ae ont. sphere than other elements. Cesium is chemically similar to potassium, which is present in the sea to the extent of 388 mg/liter, while natural strontium is present as 13 * more likely to be widely dispersed and homogeneously distributed throughout the hydro-