Question

Which of the following radio isotopes is used in the treatment of blood cancer [leukemia]?
1. Iodine - 131
2. Sodium - 24
3. Phosphorus - 32
4. Cobalt - 60
5. None of the above/More than one of the above

Answer 1

Correct Answer - Option 4 : Cobalt - 60

The correct answer is Cobalt - 60.

• Cobalt - 60 radioisotopes are used in the treatment of blood cancer [leukemia].
• Cobalt - 60:
  • Cobalt-60 (60Co) is an artificial radioactive isotope of cobalt with a half-life of 5.2713 years.
  • It is generated artificially in nuclear reactors.
  • Intentional industrial production depends on neutron activation of bulk samples of the monoisotopic and mononuclidic cobalt isotope 59 Co.
  • Measurable quantities are also generated as a by-product of typical nuclear power plant operation and may be detected externally when leaks occur.
  • In the hindmost case (in the absence of added cobalt) the incidental generator 60Co is largely the result of multiple stages of neutron activation of iron isotopes in the reactor's steel structures via the creation of its 59 Co precursor.
  • The easiest case of the latter would result from the activation of 58Fe.
  • 60Co pass off beta decay to the stable isotope nickel-60 (60Ni).
  • The activated nickel nucleus emits two gamma rays with energies of 1.17 and 1.33 MeV.

• Iodine - 131:
  • I-131 is used in medicine to diagnose and treat cancers of the thyroid gland.
  • I-131 is produced commercially for medical and industrial uses through nuclear fission.
  • It also is a byproduct of nuclear fission processes in nuclear reactors and weapons testing.
  • Pure I-131 is a non-metallic, purplish-black crystalline solid. However, because it readily binds with other elements, I-131 usually is found as a compound rather than in its pure form.
  • For medical purposes, the I-131 capsules contain small granules of I-131 sodium iodide that are designed to be swallowed by patients.
  • Liquid I-131 sodium iodide used to diagnose and treat thyroid disease is a clear liquid.
• Sodium - 24:
  • Sodium -24 can also be used in non-medical applications.
  • For instance, it is used for leak testing in industrial pipelines.
  • Due to the limited penetrating power of the sodium radiation, detectors are only able to detect the radioactive sodium at leak points.
  • Sodium 24 is also suited to this application due to its short half-life of just 15 hours.
• Phosphorus - 32:
  • Phosphorus-32 (also known as P-32) treatment uses a radioactive form of sodium phosphate.
  • Because P-32 is radioactive, it can be used to treat some diseases by injecting it into the body.
  • When P-32 is injected into the bloodstream it collects in the bone marrow where it slows down the production of new blood cells.
  • This makes it useful for treating diseases where there are too many blood cells in the blood.