Question 11: Discuss the technique and use of radioisotopes in the different fields of human activities.

ANSWER

Radioisotopes

Isotopes of radioactive elements are called radioisotopes. Radioisotopes emit radiations, which can be used for various purposes in biological and industrial sciences.  

Techniques and uses of radioisotopes

Tracer technique: Tracer technique is the major technique used in the medical field.  A Radioactive tracer is a radioactive molecule that can be sent through the body’s circulatory or urinary system, with its progress followed by a radiation-sensitive machine.

As an example, I¹³¹ is used for diagnosing the function of thyroid. A small amount of this isotope of iodine is given to the patient. Through gastrointestinal process, it reaches the thyroid in the blood. Within a couple of hours, its concentration in the thyroid gland is determined by measuring the radiation intensity.

Biological uses of radiations

The complex chemical changes in animals and plants are studied by the tracer method. For example, the process of metabolism is studied by means of radioisotope tracer.

Radiation Therapy

High energy radiations (β-particles and γ rays) penetrate deep into the human body. These are used for the destruction of unwanted and sick tissues. For example, Co⁶⁰ emit β-particles and γ rays. The isotopes of cobalt is used for the treatment of cancer. The sick tissues of cancer are destroyed by these ionizing radiations.

Medical Diagnostics

Iodine, phosphorus and cobalt concentrate in thyroid, bones and liver, respectively. These radioisotopes are used as tracer to ascertain the passage of these tracers through the body and their concentration in the diseased tissues.