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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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and discussedat lcn~Lh tileIW froz the stmclpointof its hictory, discussions. Xt sppcars that the major problcm have been io t!m taken ad coaplctcd. Thi3 has lea to the icelin~oa their part that their cfforcsWY have been ineffectual. The scccmd weakness in comumication has been within the MS structurein zssuri.ng that the rcccwwndations of tileiTG reach all appropriatesmff. It should rcaain advisory to the entireAJ2Sprogram. Copies of reports from the Comittm should be sent to the Directorsof iW Divisionsand Offices,as well directed by the ASGiSLaIiLAdministrator. The Directorsof MS l)ivi~ionsand Offices bring the
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JOMCG Lo Liverman,AM -2- Octobcr 20, 1976 9. Membcrshfpon the TTG shauld be adjuated to provide for - any chan~in~~enbershipin a uanncr that would maintain particularareas should be Gug~cstcdby the utaff. Dr; Barr and I would be pleased to diGcuss these suggestionsfurther if yOU wish. If you agree vith chcse recoaunandations,wc ui.11 bee: J. Maher, TO
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NEW YORK UNIVERSITY MEDICAL CENTER Institute of Environmental Medicine ANTHONY J. LANZA RESEARCH LABORATORIES AT UNIVERSITY VALLEY LONG MEADOW “ROAD, STERLING FOREST, TUXEDO, N.Y. MAIL AND TELEPHONE ADDRESS: 5S0 FIRST AVENUE, NEW YORK, N.Y. 10016 Brookhaven National Laboratory Upton, New York 11973 As I mentioned i.n our phone conversation this past Tuesday, (June 17) , we have now completed the measurements necessary to estimate our lower limit of detection for 241Am (in the skull bones) in the presence of elevated levels of 137C.S. Briefly, the way in which this was calculated is as follows: we started by making the assumption that cesium and potassium have approximately the same distribution in the body; if this is true then there is.approximately 6.6% of the total 137CS body burden present in the head. A further assumption was then made that the average elevated 137CS body burden i.sabout 200 nCi whi,ch would mean a head burden of approximately 13 nCi. A “phantom” head was then fabricated to contain this amount of activity and was employed to derive the background used in the calculation of a lower limit of detection of 40 nCi 241Am. Employing a safety factor of 10 and assuming that that skull contains 10% of the skeletal burden, 4000 pCi represents only 10% of one maximum permissible As we discussed, I think that the head would be the best measurement site for determining possible internal contamination for several reasons: it represents a high bone mass with very little intervening soft tissue, 241~ is a bone-seeking radi.onuclide, 137cs if present, will be in the brain which. is not a concentrator of this nuclide and which is partially shielded by the skull bones. Furthermore, as I mentioned a body burden of 12 nCi of 90Sr would not add any appreciable Bremsstrahlung background to the 241Am energy region of interest. In general, then, this site would be much more applicable to measurements of the systemic burden of this nuclide than is the anterior thorax for lung counting.
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AS you know, to our particular all of the foregoing discussion pertains measurement system using an array of thin crystal Phoswi.Ch detectors posi~ioned about the head in a geometry specific to these counting techniques. Furthermore, all of the foregoing measurements were performed inside of our whole-body counter facility. I do not know what the background would be aboard ship, however, our familiarity with this detector system has pr,oven to us that these ‘thin crystal detectors are quite directional in response “and, therefore, can easily be shielded by “shadowing” techniques. We would be interested in assisting you with these measurements and are eager to take an active part in this area of your future proposed measurements. Please let me know if you require additional specifics including budgetary considerations and man-time expenditures. We look forward to continued cooperation.
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LOS ALAMOS SCIENTIFIC L.4B0RAT0RY To give you some idea’of the plutonium daily excretion level of persons who are constantl~exposed to plutonium, I have made a simple calculation, that the person concerned acquires 4 pCi of plutoniwn per day. This acquisitionis assumed 1) to be in a soluble form in the blood stream, and 2) to be deposited in the bone and liver, and 3) to be eliminated according to Langham’s excretion equation. For a single acute uptake of D pCi in thissoluble form, Liingham’sequation predicts a 24 hour where D is the daily uptake in pCi Znis the number of days of exposure “Uz is the predicted excretion on day Zn in The attachedtable is for D = 4 pCi per day and Z is from 1 to 6fIdays by daily steps and from 90 to 2190 days (6 ,years)nin.30day steps. For smaller daily uptakes you can divide the values of column !3Zand Uz,bv the desired reduction factor. After three years (lC195”days)of exposure with the calculated uptake, the total accumulated systemic body burden would be 4330 pCi and the expected urinary excretion would be 0.163 pCi/24 hr. You stated that the sensitivity detection limit of the Health and Safety (H & S) lab runs able to detect any activity over their limit of detection, it just could be inferred that the 3 year accumulated intake by the 3ikini natives could not be in excess of .()~s
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Assuming that a systemic plutonium body burden of 40000 pCi exposes the bone to 29 rem per year, 130 pCi would correspond to an exposure of % O.1 rem per year to the bone. To me, this is an insignificant exposure. . All of the above discussion is based on the assumption of uptake of soluble plutonium into the blood stream. I have difficulty in imagining how such a continuous soluble exposure could occur. Inhalation is a possible route of exposure, but the long hold up times for insoluble plutonium in the pulmonary region and lymph nodes would make detection by urine sampling difficult (to <a-ythe least) after only three years of potential exposure. As indicated in our phime conversation our concern about plutonium exposures at LASL are at a much higher level than those expected for the Bikini natives. The urine and fecal sampling programs at LASL is given in the accompanying document, LA-3836-SOP. An early version of the computer program we use to compute systemic body burden from urine assays is described in the accompanying reprint. A later version of the computer code’is currently in use, but still in development, and has not yet been documented. The urine analysis technique at LASL does not claim the sensitivity you quoted from the Health and Safety Lab in New York. However, it has been published in Health Physics 11, 737-742 (1965) by Campbell and Moss. The following slight modif~~ation has been added to the published procedure: “Hydgroen peroxide in small quanities is added to the ash solution before the ion exchange steps to ensure formation of tetravalent plutonium, elution is accomplished with 0.36 ~HCl - 0.01 ~HF.” We also discussed correcting low volume urine samples to true 24 hr excretion. I indicated that I had reservations about appl,yingsuch corrections for natives of on Bikini atoll, and I still entertain such reservations. However, in answer to your inquiries on ways to correct, Group H-5 has developed the folIowing techniques for use here at LASL, using data collected under controlled conditions: Corrections are made by estimating the “elapsed time” (minutes) represented by the sample analyzed, and multiplying the amount of plutonium determined in the
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Dr. Robert Conrad -3- October 23, 1975 Here, at LASL we employ the specific gravit,y-v.olumecorrection, primarily because of the added work load and cost of creatinine determinations. If I can be of further se-rvice,please let me know.
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Dekrmination of Plulcmiurnin IitIW IJ rinc S:\In~]lcs Apparatus and reagent.s arc k salmc Measure out one liter ofurine with a grucluatecl cylinclcr and transfer to t.hc beaker. Rinse the cylinder with 300 ml of11N03. Carefully adcl the HN03 to the beaker, rinse the cylinder with a small amount of clcionizccl water and add to the sample. Place a glass stirring rod in the beaker to prevent bumping and cover. Place the sample on a mcclium temperatu rc hot plate and wet ash the urine sample. When the volume in the beaker is low enough to accommodate more sarnplc, add an additional liter of urine and 300 ml of llNOq. Repeat until the cnti re
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12. Transfer the paper to a 100 ml platinum dish. Dry at 11 O°C and ignite at 14. Repeat the addition and evaporation 16, Evaporate the solution to about 100 ml. Cool to room tcmpcraturc, transfer to a 250 ml graduated cylinder ancl record the volume. Rcscrvc Lhc bcalmr. 17. Dispense two 100 microliter aliquots to two 150 ml beakers containing 25 ml of aliquots with stzmdardizcd 0.1 N to a pllcl~oll]l]tllalcill cncl point. Calculate the 18, Transfer the sample from the graduated cylinder to original beaker reserved in step 16. Wash the graduated cylinder with the amount of water necessary to adjust the normality ofthe sample solution to 8& HN03.
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Enclosed is a draft copy of our paper evaluating the Pu concentrations observed in urine samples from Bikini and i;ewYork. Me plan to publish the report as a UCRL and would appreciate any comments you may have, I am also sending information copies to Bob Matters and Bill Forster of DBER and IlatBarr of DTO. It is interesting that the relative difference in observed Pu concentrations at Bikini and New York can be accounted for by the “ difference in intake of Pu via the various pathways. cou~t fcr the absolute magnitude of the Pu urine concentrations observed, We feel the Bikini data indicate that perhaps for humans, and for Pu incorporated in food products, that the transfer across the-gut wall may be considerably greater than that predicted from . animal studies. We feel this is a very significant point and we hppe that support for follow-up research, for which we have several proposals, would be supported by ERDA. . We would greatly appreciate any comments you have in the “analysis presented in the paper and also on the potential for pur- ‘suTng the metabolism of Pu ingested in food products by human