om qe Arrowroot stems and leaves show a considerable amount of activ- ity but the ratio of the activity in the supporting system to that in the edible part is much less than for coconuts. This is understandable when the relative amounts of fruit and supporting system in both instances are considered. 2.2.3 Soil Exposed soil profile, tube coring, and gross samples were collected to describe the distribution of activity in the island profiles and especially in the areas of extensive food plant production. ; A summary of the beta activity in gross samples of soilis given in Table 2.3. files. Table 2.4 presents data obtained from exposed soil pro- The probability of cross-contamination in these samples was small. TABLE 2.3 Summary of Beta Activity in Gross Samples of Soil Island Number of Samples Beta Activity (B’/min/g) : Depth of Soil «Oto lin, > lto Sin. Likiep 1 90 Utirik 4 960 §50 Rongelap 5 8,900 800 Eniaetok 2 48,000 640 Labaredj 3 85, 000 1,300 Kabelle 6 96,000 3,100 Gejeno 1 348,000 12,400 Bikar 1 8,400 30 Eniwetak 1 12,000 240 an pes oye we co s afl) *.