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Development o f Techniques and Methods f o r Medical Application and Environmental Health Problems ASSOCIATED UNIVERSITIES, INC. BROOKHAVEN NATIONAL LABORATORY initial technique developed a t BNL employed two encapsulated sources of 45 C i of 238Pu,Be, Ge(Li) detectors, and afast counting circuit. improved by changing t o 252Cf and using better shielding such that the dose i s approximately 1/3 of the original system. The system ha5 been The feasibility of using this technique and a nuclear scattering technique t o make similar measurements of other trace metals (mercury, copper, silicon,lithium,iron) has also been investigated. neutron sources has made possible the building of a transportable prompt gamma neutron activation facility which can be moved to specific populations of interest. The "portable" nature of the BUDGET A N D REPORTING CODE DATE PREPARED A new noninvasive technique for measuring total body nitrogen was developed specifically to measure the body protein content and its changes i n cancer on line, the capture of gamma rays arising from the interaction of neutrons and various elements i n the body. source. The gamma detectors in this technique are large volume sodium iodide. Total body nitrogen is measured with a very low dose (26 mrem). The technique offers a new experimental approach for the study of metabolic disorders. The method utilizes the technique o f measuring, The neutrons are derived from a 90 C i 238Pu,Be 11. Nuclear Resonance Scattering (NRS) The quant if i cation of body stores of iron rests on a newly developed technique of i n vivo nuclear resonance scattering (NRS) . usof 56Fe (92% isotopic abundance) is raised to its first excited state by gamma keV gamma ray. This gamma ray i s measured externally to the body by special detect ion instrumentation. In this technique the nucle--- The excited nucleus decays toits ground state by emission ofa 847 An instrument t o measure small amounts of iron was constructed and used i n phantom studies to demonstrate the feasibility of the technique for measuring tissue-deposited iron.A full scale instrument capable of measuring low levels of iron in the heart and liver of thalassemic patients was developed. The ca libra - tion and testing of this NRS instrument was completed i n phase 1of the study. In phase 2 , the instrument isto be used t o measure changes in iron deposits in thalassemic patients currently undergoing ch elation therapy i n research studies in the Boston and New York areas.Fat i ents will be brought to Brookhaven a t 6-12 month intervals for measurement. with hemosiderosis are being studied. In addition,patients on hemodialysis
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TITLE Deve lopment of Techniques and Methods f o r Medical Application and Environmental Health Problems ASSOCIATED UNIVERSITIES, INC. BUDGET AND REPORTING CODE DATE PREPARED 111. Whole Body Counting An essential requirement for this program was the development of a method for absolute measurement of internally deposited radio nuclides using whole with its on-line computer is unique, the most sophisticated instrument of its type in existence by virtue of its sensitivity,spatial localization, and invariant of spatial distribution and energy absorption of radio nuclides by the body. improved spatial localization of the counter results from its coincidence cir - cui try and the use of mathematical analysis.A matrix technique i s used t o extract an improved distribution profile from data recorded by the counter. With the fast data-handling facilities available with the on-line computer, the technique has also been successfully applied in studies involving rapidly distributed radioactive gases such as xenon and krypton, and radioactive particulates. It is the only system which can correct for both the effects Ata time when the use of radio nuclides is increasing rapidly, and the level of contamination of the environment can be expected to increase, it is essenti alto have available accurate instruments for the absolute measurement of low levels of internal contamination of human beings. accuracy o f the BNL 54-detector whole body counter also permits the use of low levels of tracer for the measurement of the long-term biological turnover of various jects exposed to fallout is also conducted. Whole body counting of Brookhaven employees and Marshallese subIV. Delayed Gamma Neutron Activation Ana'lysis (TBNAA) The unique Brookhaven-designed total body neutron activation facility has created a number of new research possibilities. The neutron irradiation fac il - ity employs an array of 14 encapsulated sources containing 50 C i of 238Pu,Be positioned above and below the supine patient. the use of a,n neutrons over the use of neutrons produced by cyclotrons, or of the previously used BNL neutron generator. tages is the considerable reduction i n the radiation dose to the patient (0.28 Numerous advantages derive from One of the most important of these advanPrompt gamma neutron activation analysis provides the best currently avail - able means for measuring in vivo levels of liver and kidney cadmium. Fabrication of the facility for in vivo measurements of human kidney and liver cadmium by neutron capture prompt currently employs a 552Cf neutron source and a gamma-ray detection system consisting of two Ge(Li) detectors (25% efficiency each),shielded by bismuth and a 1.5 cm layer of paraffin heavily doped with enriched lithium fluoride. The dose delivered to the liver and left kidney is <200 mrem. The detection limit is now amma ray analysis was previously described. The method