UNDERSTANDING THE USES OF RADIOISOTOPES(Radioactivity-Nuclear)

Radioactivity-Nuclear

Radioisotopes are unstable isotopes which decay and give out radioactive emissions. Sodium-22, Cobalt-60 and Carbon-14 are example of radioisotopes.
Radioisotopes have a wide range of applications including medicine, agriculture, archaeology and industry.

Medicine

Nuclear medicine is a branch of medicine that uses radiation to provide information about the function of the specific organs of a patient or to treat disease. A radioisotope is taken in by the patient through the digestive system, by inhalation or through the blood vessels by injection. The radiation emitted enables organs such as the thyroid, bones, heart or liver to be easily imaged by imaging equipment. Disorders in their function can then be detected.

Radioactive nuclei are used to detect tumors and others diseases in the organs. Organs containing tumors usually absorbed more substances than normal tissues. A small amount of a suitable substance, combined with a radioactive source, is injected into the blood, which carries it into the organ. A diagnosis is made by comparing the radiations emitted from the diseased organ with that emitted from a healthy organ. The radioactive nuclei used for diagnosis should have a short half life such as several hours or days. If the sources only emit gamma radiations, the nuclei are highly desirable because they cause relatively less damage to the body tissues due to the weak ionizing power of the radiations.

Agriculture

Radioisotopes have many uses in the field of agriculture. By measuring the radioactivity of the stem and leaves, scientists can find out how much fertilizer has been absorbed by the plant. Radioisotopes such as nitrogen-15 and phoporus-32 can be used as tracers in the study of effectiveness of fertilizers. These radioisotopes are added to soil water. After the plant absorbs the soil water, the radioisotopes can track uptake of fertilizer from roots to leaves in a plant.

Radioactive radiation is also used to induce genetic mutation in a plant in order to produce a better strain which has a higher resistance against diseases.

Radioisotopes are also used to kill pests and parasites and to control the ripening of fruits. Pests can be killed using radioactive rays especially gamma rays. The population of pests can also be controlled by exposing them to a low dosage of gamma rays. These rays induce mutation in the pests which stops them from reproducing.

Archaeology

In the field of archeology, it is important to be able to determine the age of artifacts. The amount of carbon-14 left in a decayed plant or animal can be used to tell its age. One of the most important uses of radioisotopes in archaeology is carbon-14 dating. Carbon-14 is a radioisotope with a half-life of 5730 years and decays by emitting a- particles.

How to Measuring Geological Time

"During the formation of rocks, some radioisotopes such as uranium-238 are trapped. As the decay continues, the proportion of uranium-238 decreases slowly resulting in the equally slow growth of its product, lead-206. An estimate of the age of the rock can be inferred from the relative proportions of lead and uranium in the rock."

Industries

Industries have found many uses for radioisotopes. Gamma-rays can be used to penetrate deep into welding to detect faults. Water can be made radioactive by dissolving some radioactive salt which contains sodium-24. The β-particles emitted are detected by a GM tube. The α-particles from polonium-2l0 are used to neutralize static charge in photographic plates and other materials.

Radioactivity-Nuclear