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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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2. The regional differences can not yet be defined c _-- u a o u of the ll sited data so far available. 3. The average person has less than 0.1 SOUoin his skeleton. 4. The general curve of Sr90 VS. age shows a ten fold increase i n the younger age group (5-10) but the individuals may depart radically from this. Same children have less than 0.1 S.U. whereas sme people over 30, even one 70, show Sr9O concentration considerably e and t o plan a sampling program which will include more of these. It 5. It is essential t o determine the reason f o r the high values remain lower than some Individuals by factors of r d l--.u %B.-Comon Strontium in Huinan Bone ten or more, 3 \p 1. A new emission spectrographic technique for the direct analysis d-4 of Sr in bone ash has been developed which fields good precision. analyzed and show no correlation with age, bone tpPe or 8eX. 2, A Total of 227 human bones from all over the world have been 3. There are regional variations doubtless dependent on crustal abundance for that area. 4. The human body selectively discriminates against Sr by a factor - of 10 over its n a t u r a l environment. This is consistent with biochemical tracer experiments with animals and the present strontium
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5. Because apatite generally accepts str on tim, it fs suggested that in the process of fossilization the strontium content might increase with time giving anew method for the relative chronology of fossil bone. 6. The data accumulated t o date show no correlation between Sr90 and total Strontiun present in hman bone. C. Radim in Hman Bone 1. Although widely distributed geographlcaUy, results obtained an several dozen specimens show the average radium content of hman bone to be a factor of 5 lower than previously reported. If1 t h i s is generally true the dose from SrgO i n young people is already considerably larger than for natural radium, 2. The radium concentrations are characteristic of the geographical 903* There is no obvious correlation between radium and the Sr content of human bone. This is expected on geochemical grounds. 4. There might be a correlation between radium and stable strontiun sinca. granite rocks have higher Sr/Ca and Ra/Ca ratios and basaltic rocks lower. Therefore if the d i e t directly reflected the relative concentration t h i s correlation would be found. This coypdation is 1, The techniques used gave a precision of better than 5% f o r the 2. Cabs and Sr85 are rapidly distributed through the body following
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3. The biological half U f e of sr85 i n tissue ia about 7-12 daYa over a two nonth interval, whereas the biological half life bones at least 50 day6 at the outset but probably increases rapidly after the Mt-hl period of adjustment. 4, The biologiml half life f o r CaLs ia consistently higher than 5. A masurable quantitr of Cab5 is found in both bone and s o f t tissue 32 m o n t h s after administration (ieee one half that after two 6 , The erzrichment factor in favor of calcim is somewfiat greater f o r bazle t b soft tissue. In fact soft tissues typically shaw an enrich mt in favor of strontium in the early phase after administration but ultiimtely, a f t e r 39 and 65 days show a calcium enrichment. The fractlonaticrn aga-hst strontium i n bone after a month or so appears 7, The sFcific activity of calcium(i,e. uc wen as the concentration of ~l.8s/gm. calcium is greater for tissue than fcr bow and is also greater f o r outer layers of bone than f o r the irmer kyers, T b specific activity is also greater f o r the metabolicilly active bmes like vertebra and sternum than for the long b o m s sach zs femur and humerus. PAb is intermediate and hence is a reasonabh sample of the Sr90 activity of a particular human, 10. Seprate portions of the same organ may vary by as much as a factor of two. L o c a l inhomogeneity appears to be the rule although the average value for an individual changes regularly with t h e .
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L Sr90 ana~yseain soil have a precision of better than 5%. 2. Samples taken a few f e e t away from each other may v81yby a factor of two. 3. Total base exchangeable Srm can be obtained from auccesdve ammonium acetate leaches or a singv 6N HC1 leach, 5. In most cases 80$ of the Sr9q is in 0-2". 6 . The New York area has an ave$age t o t a l integrated Sr90 fallout 7. The New York area soil shows an average of 70 Sunshine Units and a range from 1.7 t o 2% Fn the depth of 0=21t. Thus the average f o r tilled fields should be about 12 Sunshine Units yielding plants KTth about 8. By carefully selecting and mixing 10-20 soil samples from an area it is possible t o make a single measurement and determine the total integrated fallout inthe area to Within e & & ? c : ; j : y q of clover at Norfolk or Charlestcn under the conditions of maXimUm fan out are 1602100:21r0:5000. 2, The Sr90 is largely inside the plants having come from the s o u . These plants contain 3-54 Sunshine Units. 3. There was no significant geographic effect f o r the series on a uhole, however, for a given cloud there mag have been a difference of a factor of two.
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b. Clover picks up twice as much fallout debris as oats due t o the large 5;. The fallout is localized i n hot particles. 6. The surface contamination w i l l become increasingly unimportant. Thus already during a test series i n Nevada the greatest hazard t o eating unwashed vegetation i n the eastern United States has resulted from internal Sr90. 7. Milk from cows grazing i n the eastern United States during a Nevada 131test series will get a negligible quantity of I . G, Specific Activity of Venetation i n a Field of Known Sr90/Ca In a field where the soil had a consistent value of l.452 5 Sunshine Units, . a grass called Broomsedge was analyzed for its Sr9O/Ca ratio. A Value of 152 f 4 SOU, (Internal srW)indicates that the plant lives i n an average environment Of 300 S,U. since most vegetation is known t o discriminate against strontium by a factor of approxim2tel.y two, such vegetation may be a means whereby material of a high Sfso/Ca r a t i o can be introduced into the body. Since the New Pork area has a total fallout similar t o the world-wide average, people who are primarily vegetarians could i n principle be getting a consistent diet of over 100 S. U. at the presen~~T~i-~i~7~A The high number of Sunshine Units suggests that 1. Atlantic 3cean water contains negligible S.U, of S p and the surface life will probab’ly nsver comtitute a hazard, carried by surface currents neither ocean water or fish appear fruitful samples for Sr9O for the purpose of Project Sunshine.