Most synthetic radioisotopes are extremely radioactive and have a short half-life.

Most sources of these are synthetic radioisotopes.

Synthetic radioisotopes also can be detected in silt.

Some synthetic radioisotopes are extracted from spent nuclear reactor fuel rods, which contain various fission products.

Galium-68's preparation as a pharmaceutical is chemical and the radionuclide is extracted by elution from germanium-68, a synthetic radioisotope of germanium, in gallium-68 generators.

A synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time.