### Theory:

The isotopes of radioactive elements which are obtained in artificial transmutations are called radioisotopes.
About $$500$$ radioactive isotopes have been artificially produced by the bombardment of stable elements with alpha particles.

Radioactivity yields a large number of radioisotopes. These radioisotopes have been used in various disciplines, including medicine, agriculture, industry and archaeological study.
Agriculture:
• The radioisotope of phosphorus ($$P- 32$$) helps in crop production.
• Radioisotope's radiation is used to kill insects and parasites and to avoid agricultural waste.
• Certain perishable cereals exposed to radiations retain their freshness for longer than their average shelf life (time period in which the food retains its quality), extending their storage time.
• The radiation at very low amounts keeps the gram from sprouting and onions, potatoes from spoiling.
• Unnecessary plant mutations can be prevented by irradiating seeds using radio-isotopes.
• Radioisotopes are used in agriculture for selecting fertilizers.
Medicine:
In medical applications, the radioisotopes can be classified into two parts:
1. Diagnosis
2. Therapy
Radioisotopes are employed as tracers to diagnose blood circulatory disorders, bone metabolism defects, tumour location, and other conditions. Some of the radioisotopes that are used as tracers are
• Hydrogen
• Carbon
• Nitrogen
• Sulphur
 Radio isotopes Symbol Uses Radio sodium $$Na^{24}$$ Effective functioning of the heart and detects blood clots in the body Radio iron $$Fe^{59}$$ Diagnose anaemia and provide treatment Radio phosphorous $$P^{32}$$ Treatment of skin diseases Radio iodine $$I^{131}$$ Tests the functioning of the thyroid gland Radio cobalt  Radio gold $$Co^{60}$$ $$Au^{198}$$ Treatment of skin cancer and to kill cancer cells

Generally, radiations are used to sterilize surgical instruments to kill germs and microbes. Also, the radioactive gases are injected into the atmosphere to study the course of monsoon winds and their changes.