How Isotopes are used

In the late 1800s, isotopes puzzled scientists and transformed how science viewed the nature of atoms.  However, the confirmation of  and understanding of isotopes has lead to some incredible possibilities that go beyond scientific experiments. Now, these odd atoms serve as tools in modern diagnostic medicine, in cancer treatments and for everyday life.

What is an isotope?

The term isotope is a derived from the Greek words Isos, which means equal, and topos, which means place.   An isotope is a variant of a basic element, which has the same atomic number, but has a different atomic mass.  While we once thought that every stable atom has an equal number of neutrons and protons, we know now that this is not true.  In some elements, the charge remains balance and many may have one more neutron than proton.  An isotope is that atom that will not have that same balance.

Isotopes can be stable or unstable.  Unstable isotopes, or radioisotopes, emit high-energy particles (radiation) which causes them to decay.  The decay may cause a chemical atom to lose particles and possible become another isotope or another element all together.  Stable isotopes on the other hand, as the name indicates, have become what they will be and no changes will occur to their structures.

Discovery of Isotopes

The term isotope was first used by Margaret Todd, the Scottish doctor and cousin of radiochemist and Nobel Prize Winner Frederick Soddy.  Working with Nobel Laureate Ernest Rutherford,  Soddy, was able to prove that elements transmuted and this is in essence radioactivity.  Working to steps to radioactive materials (radium and uranium), Soddy was able to isolates.

How are they used

The discovery of the isotope was not only useful to chemistry but for many other disciplines. The best known use of the isotope is in nuclear weapons and energy which became reality in the 1940s.  The use of isotopes goes beyond the power of the atom bomb, though.

Read more on what are radioactive isotopes used for.

Household items

Every home has a smoke detector, but few know that smoke detectors that most hold a small amount of the isotope americium-241. By utilizing the radioactive properties americium, smoke from a fire can be detected at a very early stage. The use of this isotope technology has saved many lives.

Food and Agriculture

Certain isotopes, called radioisotopes, can be used to help understand chemical and biological processes in plants.  In the field of food preservation, food irradiation is used.  This process  is a method of treating food that makes it safer to eat and makes it have a longer shelf life. This process is not very different from other treatments such as pesticide application, freezing and canning.  And, it is effective in eliminating growth of disease- causing or spoilage-causing  micro-organisms

Other Sciences

Isotopes are even used in archaeology, the science of humanity and the study of ancient civilizations.   Carbon dating is commonly used to determine the age of artifacts and fossil remains.  The premise is based on the fact that biological organisms are carbon based life forms.  Using this information, carbon decay can be used to age the fossil remains.


With the growth of microbiology and oncology, comes the growth of diagnostic tools and treatment regiments.  Bone and organ imaging is an example of this.  By injecting radioisotopes into the body, a patient’s bones or other systems can be evaluated.  Also, chemotherapy and radiation treatments are common for most cancers.  Basically, radioactive isotopes serve as both curatives and diagnostics.

Energy and Defense

The power of the atom is an incredible thing.  We know this from the stories of the atomic bomb. So much energy is released with the power to level buildings and destroy lives. However, there is another side to the power.  Now, energy from the atom can be harnessed as nuclear power. The isotope, Uranium-235, gets most of the credit for this feat.  Through a process caused fusion, rather than fission, power is released and used to power cities.


It was once thought that atoms were indivisible bits of matter.  Present day knowledge proves this fact to be incorrect. However, from the unstable atom or the odd atom, life saving and life improving inventions and technologies have evolved.

For more information on isotopes and their uses, check out the following resources: