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Radiation Applications. Artificially produced radioisotopes find many uses in agriculture, industry, medicine, forensic science, and scientific research. The first practical application though of radioactivity was done by George de Hevesy in 1911.
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Artificially produced radioisotopes find many uses in agriculture, industry, medicine, forensic science, and scientific research. • The first practical application though of radioactivity was done by George de Hevesy in 1911. • He was a student working on naturally-occurring radioactive materials. • Suspecting that the food served to them was actually recycled food, he ‘planted’ trace amounts of the radioactive material on a particular dish.. • when that same dish was served to them, he took out his gold foil electroscope to check if the food was radioactive.
Food and Agriculture • 3 major areas where ionizing radiation is used in agriculture: (1) mutation plant breeding, (2) food irradiation, and (3) sterile insect technology. • Ionizing radiation is radiation with sufficient energy to remove an electron from an atom or molecule. • This ionization produces free radicals, atoms or molecules containing unpaired electrons, which tend to be especially chemically reactive. • .
Ionizing radiation has been used for several decades to produce new genetic lines of rice, sorghum, garlic, wheat, bananas, beans, avocado, and peppers, all of which are more resistant to pests and more adaptable to harsh climatic conditions. • IR 64 – produced by treating its breeder seed with 3 mutagens, namely: • Diepoxybutane (DEB, 0.006%) • Fast neutrons (FN, 33 Gy) • Gamma rays (GR, 250 Gy)
Food Irradiation • food preservation option; very useful in preventing growth of molds in herbs and spices. • Irradiation of food is carried out using accelerated electrons (beta radiation), and ionizing radiation from sources such as the radioisotopes cobalt-60 and cesium-137. X-rays are also sometimes used. None of these sources of radiation used have enough energy to make the exposed foods radioactive.
ensures that pests and other harmful microorganisms are not exported with the products to other countries. • highly penetrating gamma rays pass through the fruit, sterilizing without any perceptible change in the taste and texture. • also very useful in preventing growth of molds in herbs and species.
Sterile insect technique • consists of irradiating laboratory-reared male insects before hatching, the purpose of which is to sterilize them. • About 10% of the world's crops are destroyed by insects. In efforts to control insect plagues, authorities often release sterile laboratory-raised insects into the wild. These insects are made sterile using ionizing radiation - they are irradiated with this radiation before they hatch. Female insects that mate with sterile male insects do not reproduce, and the population of the insect pests can be quickly curbed as a consequence.
Diagnosis, Therapy and Medical Uses • Radiation is a powerful tool in medicine especially as an aid to diagnosis. • Vocabulary • Radioisotopic tracing-using small amounts of short-lived radioactive isotopes injected into the patient’s body—a technique • Radiotherapy-a procedure where radiation beams are used to treat patients • Diagnostic Radiology- the use of x-rays for examining patients • Nuclear Medicine- the use of pharmaceuticals labeled radionuclides for diagnosis or therapy
Ionizing radiation has two very different uses in medicine: • Diagnosis • Therapy • Both are intended to benefit patients and, as with any use of radiation, the benefit must outweigh the risk. • Diagnostic uses of radiation can be considered according to the type of detector used as well as according to whether the source of the radiation is outside or within the patient's body.
The former case, "passive" investigation-is typified by conventional X-ray imaging: the physical basis of the information is the transmission (or in some cases the scattering) of radiation as it passes through the body. • "Active" investigations-are typified by the "gamma camera" and "PET" scanner: a radioactive biochemical is introduced into the body and the radiation is detected by position- or direction-sensitive means, so that the site within the body can be established. • Therapeutic uses of ionizing radiation are now limited almost exclusively to the treatment of cancer.
Prior to 1960 irradiation was used as an alternative to surgery for the removal of such tissues as tonsils and adenoids. Consequently, there are now many middle-aged people at greatly increased risk of thyroid cancer, because of the exposure that organ received from scattered radiation or from radiation that had passed through the target tissues and on into the thyroid. Such radiation treatments work by killing the target cells without killing the individual.
Group 4- Radiation Applications Members: -Abigail Joy A. Abing - Sigrid Angkang - Rody Rica Bandilla - Alen Mae Budiongan
