Note 12 PLUTONIUM ANALYSIS In the case of radionuclides that emit beta rays (strontium-90) or alpha particles (transuranics), and whose range in tissue is at most a centimeter down to some micrometers, two methods have been used for assay. (a) Knowing the daily urinary excretion, the body content of radionuclide is calculated from knowledge of its metabolisa. The method has worked for strontium-90 (e.g., 3 Rongelap cases at autopsy confirmed urinary analysis (Ref. Conard 1980, Appendix, p. 115), but not so far with plutonium where extremely small quantities are involved. (b) The dose can also be calcula¥ed from the diet. The primary obstacle here is that the diet is difficult to ascertain accurately. The Livermore results are based on this method. For Rongelap, diet and urine methods are in frank disagreement. The Livermore diet method finds the daily intake of [(transuranics] to be about 0.4 pCi/d (Section 4.2; plutonium-239 is about 50% of the transuranic mixtures). On the other hand, plutonium-239 excretion about 5 x 10 -3 pCi/d. than .07 pCi/d to about the current analysis of urine at Brookhaven gives values which range from less than 1 x 10-5 to These correspond to a range of intake from less 38 pCi/day. The doses (30-year, whole-body) calculated from these estimates for plutonium-239 are as follows: Livermore: Brookhaven: [.008 ren] .003 rem - 1.48 rem The total dose for the three transuranics (two plutoniums plus americiun) would be twice these figures. The. problems implicit in this comparison require some detailed discussion. Brookhaven results. Historically, we may begin with Conard's twenty-year Rongelap review of 1975 (Ref. BNL 50424) in which the results of urine analysis for 10 Rongelap persons were reported (Appendix 12, p. 147). One result seemed much too high; the average of the other nine was 58 x 10-3 pCi/liter/d, twice the maximum found in the current series. Conard did not discuss this result, but it was reviewed by an ad hoc group which suggested contamination as a likely cause of the high values (Lessard 1984). Urines were again collected on a much larger scale in 1981. The PARALS method was applied, but abandoned owing to inherent contamination with polonium. The fission track method was then adopted and a method to separate plutonium for such analysis worked out. It should be recognized that the very small quantities of plutonium involved make the operation of the method a very difficult task (ORAU, 1987). about $1,000. 76 5000b82 The cost per sample is