Radioisotopes allow treatment and diagnosis of medical illnesses without the cost and trauma of open surgery (which carries risks like infection, accidents, and long recovery periods). The use of Tc-99m produces hot-spot images, which reveal early signs of disease and map how organs are functioning. The low energy gamma radiation it emits, the small dose in which it's injected and it a short half-life (6hours), minimises damage to tissues. The patient's total exposure to …showed first 75 words of 493 total…

…showed last 75 words of 493 total…to reduce body's exposure to radiation. The expended radioisotopes must be shielded to prevent radiation exposures to staff and public. Those with longer half-lives are particularly problematic. Strontium-90 (half life: 28 years) is used in thickness gauges in industry to monitor and control the thickness of materials such as steel sheets, paper, foil, and plastic film. It decays to yttrium-90, which emits high-energy beta-particles. This imposes greater health risks if Sr-90 is released to the environment