Figure 20 and Table 14 @ive the decay data. Kidney decay, like kidney decline, was comparatively gradual, indicating the uptake of longer-lived radioisotopes by this, than by other clam tissues. The comparison of decay and decline in the last two columns of Table 14 shows that decay and decline vere approximately equal. Table 14. Decay retes fer tridecnia elem tisesves fren Belie. Ostia fer Pigure 30 Curve manber Plate number Tiseve bete of eollestion fegetive slope, firet te leet pointe veeey 1 8 114000 11608) ausele viseerel ance ofrise 8/7/34 ‘ 8 11316 $660 Bieney niemo sane A 3 6 ? 6 12e0h) $414 66n6 8660 gi 2 Ei @ney .80 1.07 77 6 nn 7h ‘3 73 6 9 72 nee a/e/ee 0/le/ee ie 8 1.3 2 0 a »00 8/19/80 1.1 1.07 ui@ney 13325 1331S 1lsie) anntle glk ausele as 11317 wieeeral ance lleéw 5 eases ® 0 la Kiamey ° 10 4a ls 9/7/ee beeline name 5 Tad ° 6 71 7 The equality of decline and decay rates is further substantiated by a method used by Held (1957) on samples of hermit crab carapace. If samples collected soon after detonation decay to the same levels observed for samples collected at later dates, then the rate of decl‘ne would be equal to the rate of decay; in fact, decline could be accounted for solely on the basis of physical decay. Such an equality was demonstreted by recounting clam kidney samples in October 1957, 2 to 3 years after they were collected. When the 39 available plates of clam kidney collected 6 to 536 days after Nectar were thus recounted in October 1957 the levels of radioactivity were randomly scattered from 2,000 to 10,000 without any trend that could be related to date of collection. That is, the early samples were neither higher nor lower than the later samples, ina statistical sense. The correlation coefficient of log activity related to log days after May 14, 1954 was .05, which, for 37 degrees of freedom falls short of even the 10% level of P. Results were similar to recounts of samples of snails and sea cucumbers which are graphed in Pigures 24 and 30 respectively. Clam kidney resembled snail tissues in that eariy and later samples were alike when recounted in 1957, while for most sea cucumber tissues the aarly sascles tended to be more radioactive than later samples when all were recounted in 1957.

Select target paragraph3