But use of radiation on the human body can carry many side effects. For instance, the high-energy beta-emissions from Co-60 used in radiotherapy for cancer can destroy healthy cells, and cause hair-loss, skin burning, sweating, fever, pain, or decreases in the levels of different blood cells.
Gamma sterilisation (using Caesium-137) of bandages and surgical equipment has greatly reduced the spread of infection and made surgery safer. Radiation irradiation of foods (using Carbon-14) increases shelf life and kill off any pathogens present in the food. This allows for safer foods, and lowers costs due to spoiling, but may also break up vitamins or nutrients in the food, decreasing its nutritional value.
Even minute amounts of radioactive material can be detected easily, which makes it ideal for use in tracing the movements of water, gases or even insects. In particular, the use of radio-tracers for leak detection in industry has made it possible to quickly locate and fix the leak with little disruption to the industrial process. However, the release of the radioisotope to the working/natural environment through the leak creates the danger of radiation exposure - for this reason, radioisotopes with short half-lives (like Na-24, half-life = 15hours) is used so radioactivity quickly disappears and the water/oil becomes safe to use again and the surrounding environment unaffected.
The two main problems associated with all radioisotopes are exposure to radiation by staff/public, and disposal.
alpha, beta and gamma radiation can all disrupt normal cellular processes by stripping electrons from biological molecules (like DNA and proteins), forming ions and radicals, which affect the functioning of these molecules. Widespread DNA damage may lead to development of cancer. Initial symptoms of radiation sickness may include weakness, anorexia, vomiting or diarrhoea.
Thus, personnel working with radioactive substances in industry, medicine, or research must wear face masks (prevent ingestion of alpha-emissions - can be stopped by skin, but highly ionising and causes serious cellular damage if ingested) or protective clothing (lead vests), 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