Gamma emitting radioisotopes in samples of plankton. Values expressed as per cent of the total radioactivity contributed by each radioisotope at the time of collection. Ss amoptle Percent Radioisotope P-6 Mo99-T:98m 31 Np239 O, a &y “hoy “& 2.2 P-13* Pp-15% 67 17 activity P-15 P-17 62 13 Pp-25 P-26 P-34 P-35 3.6 5.3 81 74 3.6 2.7 0.6 0.9 2.0 1.9 Rul03_Rp103 3.0 1,5 0.8 0.3 1.1 1,0 Bal40-1,,140 2.9 2.4 0.7 2.2 4,4 2.3 Te 132-7132 1.4 7.3 5.4 9.9 Zr95-Nb?9 1.1 nd 0.7 1.7 Cel44_pr144 0.6 nd nd Rul06_py106 0.3 nd nd y237 nd** 11 Rul05_Rp105 nd nd nd 100 360 140 x 108 ws 73 total Cel4l-prl4l Total d/m/g on 56 P-13 of * Small plankton. xe Not detected 13 0.3 0.3 12 0.5 0.1 nd 1.2 7.0 150 nd nd nd nd 2.0 nd 15.0 3.3 nd 8.6 -O02- Table 3,