RADIOACTIVE ISOTOPES ARE USEFUL AS TRACERS AND FOR MEDICAL IMAGING

Fertilizer with radioactive isotope appiied to crop 

Used in the study of bone formation in mammals Used to inspect airline luggage for explosives 

Used for life-science and drug-metabolism studies to ensure safety of potential new drugs 

Used to test integrity of pipeline welds, boilers, and aircraft parts 

Used in cardiology and for tumor detection Used in lung-ventilation and blood-flow studies 

Jlinto molecules whose location can then be traced by the radiation they emit. When used in this way, radioactive isotopes are called tracers  

Tracking fertilizer uptake with a radioactive isotope. 

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Radioactive Isotopes Are Useful as Tracers and for Medical Imaging... 

RADIOACTIVE ISOTOPES ARE USEFUL AS TRACERS AND FOR MEDICAL IMAGING... 

Because exposure to radiation is a health risk, the administration of radioactive isotopes must be monitored and controlled carefully. Isotopes that emit alpha or beta particles are not used for Imaging, because these radiations cause substantial tissue damage. Specificity for a target organ is essential so that the amount of radioactive material can be kept as low as possible. In addition, an Isotope for medical Imaging must have a decay rate that is slow enough to allow time to make and administer the tracer compound, yet fast enough rid the body of radioactivity in as short a time as possible. 

In a technique known as medical imaging, tracers are used in medicine for the diagnosis of internal disorders. Small amounts of a radioactive material, such as sodium iodide, Nal, which contains the radioactive isotope iodine-131, are administered to a patient and traced through the body with a radiation detector. The result, shown in Figure 4.11, is an image that shows how the material is distributed in the body. This technique works because the path the tracer material takes is influenced only by its physical and chemical properties, not by its radioactivity. The tracer may be introduced alone or along with some other chemical, known as a carrier compound, that helps target the isotope to a particular type of tissue in the body. 

Radioactive tracers are used for tracking compounds in an organism and for charting the movement of pollutants. Many different isotopes function as medical tracers for imaging organs and processes inside an organism. 

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