Isotopes for Medicine and the Life Sciences (1995) / Chapter Skim
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4 ACCELERATOR-PRODUCED RADIONUCLIDES AND A NATIONAL BIOMEDICAL TRACER FACILITY
4 ACCELERATOR-PRODUCED RADIONUCLIDES AND A NATIONAL BIOMEDICAL TRACER FACILITY
Pages 57-80
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From page 57... ...
After the War, the widespread use of radioactive materials in medicine led to the establishment of the new field of what was then called atomic medicine, which was later called nuclear medicine. Although the first artificially produced radionuclides came from Lawrence's cyclotrons, it was another 30 years before accelerator-produced radionuclides began to play a major role in the production of medically important radio 57
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From page 58... ...
As a result a number of radionuclides that are used extensively by the biomedical research community are not available from commercial suppliers because of management decisions associated with profitability. In addition, major North American accelerator installations such as the Brookhaven Linac Isotope Producer (BLIP)
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From page 59... ...
A potassium analog, 20lT1 is readily extracted in proportion to regional blood flow within heart muscle, and at equilibrium, its distribution provides an assessment of the amount and location of viable heart muscle. Single-photon emission computed tomography (SPECT)
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From page 60... ...
Still largely a research tool, PET already promises to have important clinical applications to heart disease, cancer detection, and cerebral dysfunctions caused by ischemic, degenerative, convulsive, and psychiatric disorders, as well as the detection of metastatic tumors. SUPPLIES AND SUPPLIERS The issue of accelerator-produced radioisotope availability has been subdivided into three categories, recognizing that there are essentially three sources: commercial radioisotope and radiopharmaceutical companies, site-specific cyclotrons that produce short-lived PET radionuclides for immediate use, and several large government accelerator facilities where isotope production for both industry and research is "piggybacked" onto other missions.
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From page 61... ...
. TABLE 4-2 Main Commercial Radionuclides Used in 1982, 1990 and 1992 Estimated Life Science Retail Use (~Ci/year, time of end use)
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From page 62... ...
PET could expand beyond the large medical center and become a truly routine clinical tool if some additional sources of positron-emitting radionuclides could be found. One possibility is the supply of medium half-life radionuclides from an NBTF.
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From page 63... ...
have served as the primary sources for most of the accelerator-produced radionuclides used in research in the United States. A brief description of these facilities will be given, along with a description of the TRIUMF facility in Vancouver, British Columbia, Canada, since its radioisotope production capabilities could, and do, supplement the DOE-sponsored effort.
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From page 64... ...
64 o ho o o Cal ·_1 3 Ct .e ¢ o o U)
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From page 65... ...
LAMPF At present, six products represent the major production efforts at the LAMPF (copper-67, germanium-68, strontium-82, aluminum-26, arsenic-73, and cadmium-109~. However, another dozen or so radioisotopes are available either in stock or as by-products from routine production.
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From page 66... ...
Because Los Alamos National Laboratory is distributed over a wide geographic area connected by public roadway and the shielded container does not meet current U.S. Department of Transportation standards for public transit, this shipment demands extensive coordination and requires about 24 hours from the time of removal of the targets to their arrival at the processing unit.
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From page 67... ...
, designed by TRIUMF and recently completed by another of TRIUMF's industrial partners, EBCO, will be dedicated to isotope production, primarily for PET research at TRIUMF. The TRIUMF long range plan requests some $700,000 for a new, highly automated Radiochemistry/Isotope/Pharmaceutical Laboratory for the separation of radiochemicals from targets, the preparation of new radiochemicals that mimic chemicals used in metabolism, and experiments, including animal tissue preparations, that indicate the suitability of these chemicals and associated pharmaceuticals.
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From page 68... ...
It is important to note that, in choosing the reaction and production rates, it has been assumed that, for those reactions requiring enriched targets, these isotopes are available in reasonable quantities. When alternatives were available, the reaction requiring the lowest possible energy was chosen since the low-energy reactions, in principle, produce less waste material and have the potential for higher specific activity because of the lower production rates- of neighboring stable or long-lived isotopes of the desired product.
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From page 69... ...
ACCELERATOR-PRODUCED RADIONUCLlDES TABLE 4-6 Radionuclides Proposed for NBTF with Possible Reactions and Theoretical 24-Hour Yields for a 500-,uA Beam 69 Enriched Target (% natural Yielda Production Energy abundance (mCi/ (mCi/day Radionuclide Reaction (MeV) of target)
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From page 70... ...
The $3 million upgrade goals for the linac are to increase its beam current from its present 40 HA to something approaching the design specifications of 150 HA, to provide energy variability from 66 to 200 MeV in 21-MeV steps, and to add to the production capabilities that three isotopes are currently only available from LAMPF. The $6 million upgrade to the BLIP facilities covers the construction costs involved in the upgrade and expansion of Building 801 hot cells, a structural addition to the BLIP target irradiation building, and modifications of the linac to enhance reliability at high currents.
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From page 72... ...
; the requirement that the production facilities be self-supporting (Public Law 101-101) , in concert with DOE policy forbidding competition with the commercial sector; the perception of isotope sales and distribution as secondclass activities for a major research laboratory; the relative isolation of these two laboratories from major shipping centers.
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From page 73... ...
The post-irradiation physical and chemical states of both the target and the radionuclides produced must be known for costeffective and efficient separation to ensure not only pure, high-specific-activity radionuclides but also maximum reuse of often expensive enriched target material. Some well-known radionuclide production targets could be improved substantially by focused engineering research.
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From page 74... ...
A persistent difficulty with this arrangement has been that support for nuclear science education, because it covers a very broad spectrum, has been spread widely throughout various departments within DOE, none of which feels responsible for the entire program and all of which give it a relatively low priority. Between 1989 and 1993, congressionally mandated support was provided through the University and Science Education Program, which provided funds for nuclear education
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From page 75... ...
An association with established research programs in nuclear medicine, radiopharmacy, or radiochemistry at an affiliated university would in turn provide NBTF with continuing sources of extramural collaborations, inexpensive labor, and intellectual stimulation. Pre- and postdoctoral fellowships, faculty scholarships, and incentives for new faculty positions should thus be part of DOE's core support for NBTF, supplemented by industry and government (DOE and others)
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From page 76... ...
There is also concern about each of these facilities because of their ages and the changing missions for which they were constructed. The future outlook for LAMPF is not clear, and the expertise that has been assembled there over the years will be lost when the accelerator facility is shut down.
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From page 77... ...
2. Until such a facility is established, the needs of the isotope user community should be met by an upgraded BLIP supplemented by additional operating funds to allow for an extended operating period and a processing and distribution section that is similar to that at the University of Missouri Research Reactor.
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From page 78... ...
1991. National Biomedical Tracer Facility Planning and Feasibility Study.
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From page 79... ...
1989. Proceedings of the DOE Workshop on the Role of a High-Current Accelerator in the Future of Nuclear Medicine, Report No.
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