Useful Applications of Radioactivity

The damaging aspects of nuclear radiation must always be kept in mind, especially when the possibilities of accidental or unintended exposures are great. However, the radiation from radioisotopes can be put to beneficial use. 

In some parts of the world, stored-food spoilage may claim up to 50% of the food crop. In the United States, refrigeration, canning, and chemical additives reduce this figure considerably. Still, there are problems with food spoilage and contamination. Food protection costs amount to a sizable fraction of the final cost of food. 

Carbon has three isotopes. Two of these, carbon-12 and carbon-13, comprise 98.9% and 1.1%, respectively, of all carbon. A third isotope, carbon- 

The FDA approved irradiation of beef in December 1997 in response to concerns due to food poisoning and product recalls of contaminated hamburger meat. 

Uncooked beef Control of food-borne pathogens 

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What are some of the useful applications of radioactive isotopes, including energy production ... 

Nuclear processes provide humankind with a double-edged sword. On one hand, there are many useful applications of radioactive substances in science and medicine. Nuclear power is, and will continue to be, an important soiuce of energy. On the other hand, there is always the danger of radioactive or fissile materials being used to threaten people s lives. No one can make radioactive or fissile materials just go away. Hopefully, wisdom will prevail, and peaceful applications of nuclear materials will dominate their use. 

One of the first chemical applications of radioactive tracers was a set of elegant experiments on photosynthesis performed in the 1950s by Melvin Calvin. His goal was to determine the set of reactions used by plants to transform atmospheric CO2 into carbohydrates. Calvin supplied growing plant cells with CO2 enriched with 14... 

Even nowadays the application of radioactive isotopes is the most sensitive method for the analysis of biomolecules or their reaction products. Besides the low detection limits, the replacement of a naturally overbalancing stable isotope by its radioactive analogue does not interfere with the physical or chemical properties of the enzyme (with some exceptions for hydrogens). Figure 6 lists some frequently used radioactive isotopes and their half-life periods. 

E = 137keV). The accompanying emission of 7-radiation can be used for scintigraphic imaging but also makes patient isolation necessary. The different half-lifes and /3 -energies allow individual therapeutic demands such as the pharmacokinetics of the tracer molecule, the linear energy transfer of the nuclides or the biodistribution and clearance of the radiolabeled drug to be met. The principles of the application of radioactive materials for therapy are summarized in an excellent review. ... 

Special properties of radioactive nuclides (isotopes of an element, Chapter 2) make them useful tracers for following complex processes. Radiochemistry is the branch of chemistry which involves the applications of radioactivity to chemical problems, as well as the chemical processing of radioactive substances. 

W. J. Whitehouse, J. L. Putman, Radioactive Isotopes - An Introduction to their Preparation, Measurement and Use, Clarendon Press, Oxford, 1952 E. Broda, Th. Schonfeld, The Technical Applications of Radioactivity, Vol. 1, Pergamon, Oxford, 1966... 

Nuclear Regulatory Commission. (NRC). A federal agency established in 1975 to regulate all commercial uses of atomic energy, including construction and operation of nuclear power plants, nuclear fuel reprocessing plants, and research applications of radioactive materials. It is also responsible for safety and environmental protection. Its offices are at One White Flint North, 11555 Rockville Pike, Rockville, Maryland 20852-2738. 

The peaceful application of nuclear reactors after World War II initiated the production of large quantities of radionuclides, which were introduced to medicine for the investigation of human physiology and disease. The application of radioactive tracers for clinical diagnosis and therapy increased hy the year, resulting in the widespread use of radioisotopes in clinical procedures. 

Lead-210 formed in the atmosphere via Rn which diffuses from the earth s surface is adsorbed to aerosols or dust particles, and gradually deposits on to the earth s surface. It is not in radioequilibrium with Ra, and is referred to as unsupported Pb . Thus, after being deposited, atmospherically derived Pb can be distinguished as an excess of associated Ra, and can be used as a radioactive tracer. An extensive discussion of the origin and the scientific applications of radioactive lead has been provided by Wise (1980). Beryllium-7 is formed by cosmic ray spallation of... 

Hevesy and Paneth, in the first application of radioactive trace elements, determine the solubility of PbCrO using RaD. 

One of the earliest applications of radioactive tracer techniques to surface investigations is that of Paneth and Vorwerk/ who used the Pb isotope, thorium B, to determine the surface area of powdered PbS04 by exchange between the surface Pb ions of the solid and the radioactive Pb in solution. Since then a vast number of studies of catalytic systems involving the use of radioisotopes have been reported. As the earlier literature has been extensively reviewed by Campbell and Thomson, the present Report is mainly concerned with the literature published between 1970 and mid-1982, particular emphasis being placed on new developments in experimental methods. 

Applicability of radioactive tracer tests to actual radionuclide measurements is always in question because the radionuclide in the sample may be in a different chemical or physical form. If the radionuclide has multiple oxidation states in nature, e.g., iodine or plutonium, a tracer study will be applicable only if the initial step in the procedure provides for the interchange of all possible oxidation states, or if tracers have been used in all possible oxidation states. Tests can become even more elaborate if the radionuclide of interest is an integral part of a solid sample matrix, e.g., biological material or soil. 

N), are widely used in drug metabolism studies because the tracers can be recognized and quantified by virtue of their decay profiles or mass differences. The application of radioactive and stable isotopes in... 

The determination of the residence time distribution of a process is probably the most used industrial application of radioactive tracers. The residence time distribution is the probability distribution of the time a piece of material is likely to spend in the process. The knowledge of this distribution is important when designing the process, as well as when the process is operated, in order to optimize the process operation conditions. The residence time distribution... 

One form of radiation therapy is isotope therapy, in which a labeled substance that is known to accumulate in the defective organ is introduced into the body. The radiopharmaceutical may be a compound labeled with radioactivity or a radioactive isotope that has the tendency to accumulate. The most-used application of isotope therapy is the use of radioactive iodine I to treat hyperthyroidism and cancer of the thyroid. The rest of the treatments are covered by treatment of blood illnesses with compounds containing radioactive phosphorus or the treatment of joints with the yttrium isotope... 

A useful application of half-lives is radioactive dating. No, radioactive dating has nothing to do with taking an X-ray tech to the movies. It has to do with figuring out the age of ancient things. 

One of the most valuable applications of radioactivity is in the use of radiotracers for medical diagnosis. Radiotracers are radioactive atoms that are attached to biologically active molecules. The resultant radioactivity is monitored to check on the functioning of organs such as the heart or to trace the path and final destination of a drug. 

Chapters 16 (waste disposal). Chapter 17 (radioactive materials transportation), and Chapter 18 (decontamination and decommissioning) are related to many radioactive processes and materials. Radioactive waste is generated wherever radioactive materials are handled and used. This includes medical applications of radioactive isotopes and their production, as well as the facilities and processes involved in nuclear power. This waste must be stored and/or disposed of in a way that isolates it from the environment until the radioactive materials decay. 

Radioactivity is also used to diagnose and treat many other conditions, including cancer, thyroid disease, abnormal kidney and bladder function, and heart disease. These examples from medicine are just a few of the many applications of radioactivity. Naturally occurring radioactivity allows us to estimate the age of fossils and rocks. Radioactivity also led to the discovery of nuclear fission, used for electricity generation and nuclear weapons. In this chapter, we explore radioactivity—how it was discovered, what it is, and how it is used. 

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