Radionuclides in medicine

For the disposal of L IL SL generated at the Swedish NPPs a repository has been established in crystalline rock (as required by the Swedish strategy) 50 m under the seabed outside Forsmark NPP. Following an agreement with the Government and the authorities the repository is also used for radioactive waste from Swedish use of radionuclides in medicine, research and industry that meets the waste acceptance criteria approved by the authorities for the repository. 

Application of radionuclides in life sciences is of the greatest importance, and the largest single user of radionuclides is nuclear medicine. Shortly after the discovery of Ra in 1898 by Marie Curie and its subsequent isolation from pitchblende in amounts of 0.1 to 1 g, the finding that this element was useful as a radiation source led to the first application of radionuclides in medicine. In 1921, de Hevesy investigated the metabolism of lead in plants by use of natural radioisotopes of Pb. 

Nuclear and radiochemistry includes accelerator/reactor chemistry for isotope production, nuclear structure, neutrino chemistry, nuclear forensics, and archeometery. Understanding of nuclear and radiochemistry underlies the availability of adequate supplies as well as proper and safe use of radioactivity for energy production or radiomedicine. Twenty percent of electric power in the United States is supplied by nuclear reactors. It is possible that construction of new reactors in the United States will resume within the next decade. Similarly, the use of radionuclides in medicine, research, and industry is predicted to increase. 

In 1950, the Food and Drug Administration (FDA) officially recognized iodine-131 as the first radioactive new drug. By that year, 3,250 publications had been about the use of radionuclides in medicine. The time had come for a professional organization to be formed to bring together persons interested in atomic medicine. Robert R. Newell of... 

Radioactive contamination can result from either expected or accidental release of radionuclides during the treatment of uranium ores, the operation of nuclear reactors, the processing of burnt fuel elements from nuclear reactors, or the application of radionuclides in medicine, research, industry, and agriculture, as well as from radioactive fallout from the atmosphere. 

Nuclear reactions involving technetium have been actively studied until today. Our interest in the nuclear chemistry of technetium is based on various reasons. Technetium was the first artificially produced element in the periodic table, a weighable amount of technetium ("Tc) is now available, and 99mTc is one of the most important radionuclides in nuclear medicine. In addition, technetium is an element of importance from a nuclear safety point of view. 

Nuclear explosions and nuclear power production are the major sources of anthropogenic activity in the environment. But radionuclide use in medicine, industry, agriculture, education, and production and transport, use, and disposal from these activities present opportunities for wastes to enter the environment (Whicker and Schultz 1982a Table 32.6). Radiation was used as early as... 

Nuclear explosions and nuclear power production are the major sources of human radioactivity in the environment. Other sources include radionuclide use in medicine, industry, agriculture,... 

The specific techniques of brachytherapy and the administration of unsealed sources of radionuclides, in nuclear medicine [10], are not dealt with in this chapter. 

Edetate calcium disodium is indicated chiefly for the chelation of lead, but it may also have usefulness in poisoning by zinc, manganese, and certain heavy radionuclides. In spite of repeated claims in the alternative medicine literature, EDTA has no demonstrated usefulness in the treatment of atherosclerotic cardiovascular disease. 

Radiochemistry is defined as the chemical study of radioactive elements, both natural and artificial, and their use in the study of chemical processes (Random House Dictionary, 1984). Operationally, radiochemistry is defined by the activities of radiochemists, that is, (a) nuclear analytical methods, (b) the application of radionuclides in areas outside of chemistry, such as medicine, (c) the physics and chemistry of the radioelements, (d) the physics and chemistry of high-activity-level matter, and (e) radiotracer studies. We have dealt with several of these topics in Chapters 4, 13, 15, and 16. In this chapter, we will discuss the basic principles behind radiochemical techniques and some details of their application. 

Nuclear Medicine—Factors Influencing the Choice and Use of Radionuclides in Diagnosis and Therapy (1982)... 

Radiopharmaceutical Kits Radiopharmaceutical kits are nonradioactive ( cold ) products containing the sterile ingredients needed to prepare the final radiopharmaceutical. Immediately before administration to the patient, the radionuclide is added. From the point of licensing, these semimanufactured products are defined as radiopharmaceuticals, as they have no other application in medicine [2],... 

The dimension is s , and the unit is called becquerel (Bq) 1 Bq = 1 s . An older unit is the curie (Ci). It is still used sometimes, related to the activity of Ig of Ra, and defined as 1 Ci = 3.700 lO s = 37GBq. Smaller units are 1 milli-curie (mCi) = 37MBq, 1 microcurie (ixCi) = 37kBq, 1 nanocurie (nCi) = 37 Bq, and 1 picocurie (pCi) = 0.37 Bq. 1 Ci is a rather high activity which cannot be handled directly but needs special installations, such as hot cells. Activities of the order of several mCi are applied in medicine for diagnostic purposes, activities of the order of 1 pCi are usually sufficient for the investigation of the behaviour of radionuclides, and activities of the order of 1 nCi are measurable without special efforts. 

Sometimes high or well-defined specific activities are required, for instance in the case of the application of radionuclides or labelled compounds in medicine, or as tracers in other fields of research. 

The Mo/ Tc generator is the most frequently used radionuclide generator in medicine, due to the favourable properties of (half-life 6.0 h IT by emission of... 

Labelled compounds have found broad application in various fields of science and technology. A great variety of labelled compounds are applied in nuclear medicine. The compounds are produced on a large scale as radiopharmaceuticals in cooperation with nuclear medicine, mainly for diagnostic purposes and sometimes also for therapeutic application. The study of metabolism by means of labelled compounds is of great importance in biology. More details on the application of radionuclides and labelled compounds in medicine and other areas of the life sciences will be given in chapter 19. 

Generator-produced radionuclides are also introduced into compounds suitable for specific applications, in particular in medicine. For Instance, " TcOj eluted from a Mo/ Tc radionuclide generator can be introduced into organic compounds by various chemical procedures that can be performed by use of special kits which allow easy handling. 

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