Uses of Radioisotopes
Isotope | Radiation Emitted | Half-life | Use |
Carbon-14 | beta | 5730 years | radiometric dating:determination of age of carbon-containing artifacts up to about 70,000 years also used as a biological tracer, for example, in studies of photosynthesis Naturally occurring radioisotope |
Chlorine-36 | beta | 301,000 years | measurement of sources of chloride and determining the age of water up to about 2 million years old Naturally occurring radioisotope |
Lead-210 | beta | 22.3 years | date layers of soil and sand deposited up to about 80 years ago Naturally occurring radioisotope |
Tritium | beta | 12.32 years | measure the age of 'young' groundwater up to about 30 years old Naturally occurring radioisotope Titriated water is used to study sewage and liquid wastes |
Potassium-40 | positron emission | 1.26 billion years | Potassium-Argon radiometric dating:100 000 to several billion years |
Rubidium-87 | beta | 48 billion years | Rubidium-Strontium radiometric dating:millions of years |
Uranium/Lead | U-238 alpha & gamma | 4.5 x 109 years | radiometric dating:millions to billions of years |
Oxygen-18 | stable | biological tracer, for example, in studies of photosynthesis | |
Sodium-24 | beta, gamma | 15 hours | location of leaks in water pipes, studies of body electrolytes Isotope prepared in a nuclear reactor |
Magnesium-27 | beta, gamma | 9.5 minutes | location of leaks in water pipes |
Potassium-42 | beta & alpha | 22 hours | determination of exchanged potassium in blood flow Isotope prepared in a nuclear reactor |
Chromium-51 | alpha | 27.7 days | labelling of red blood cells & quantifying gastro-intestinal protein loss Isotope prepared in a nuclear reactor |
Iron-59 | beta, gamma | 46.3 days | in blood studies, when incorporated into steel it is used to determine the amount of friction in machinery |
Cobalt-60 | beta, gamma | 5.3 years | cancer treatment as tumour cells tend to be more susceptible to radiation than other cells |
Gallium-67 | gamma | 3.3 days | tumour-seeking agent Isotope prepared in a cyclotron |
Krypton-81 | gamma | 13 seconds | Isotope prepared in a cyclotron |
Technetium-99 | beta | 6 hours | Medical tracer used to locate brain tumours and problems with the lungs, thyroid, liver, spleen, kidney, gall bladder, skeleton, blood pool, bone marrow, salivary & lacrimal glands & heart blood pool & to detect infection Isotope prepared in a nuclear reactor |
Iodine-131 | beta, gamma | 8.1 days | Medical tracer to study & treat the thyroid gland & used in the diagnosis of adrenal medullary & for imaging suspected neural crest and other endocrine tumours Isotope prepared in a nuclear reactor |
Iodine-123 | gamma | 13.2 hours | used in imaging to monitor thyroid function & detect adrenal dysfunction Isotope prepared in a cyclotron |
Ytterbium-169 | gamma | 3 days | Isotope prepared in a nuclear reactor |
Uranium-235 | alpha, gamma | 7.1 x 108 years | enriched as a fuel for most nuclear reactors |
Plutonium-239 | alpha, gamma | 24 400 years | fuel for most "fast-breeder" nuclear reactors |
Americium-241 | alpha | 432 years | domestic smoke alarms & neutron gauging Americium-241 is a decay product of plutonium-241 formed in nuclear reactors. |
Copper-64 | gamma | 12.7 hours | studying genetic disease affecting copper metabolism Isotope prepared in a nuclear reactor |
Iridium-192 | beta | 73.83 days | supplied as a wire for use as an internal radiography device |
Molybdenum-99 | beta | 66 hours | used as the 'parent' in a generator to produce technetium-99m, the most widely used radioisotope in nuclear medicine Isotope prepared in a nuclear reactor |
Phosphorus-32 | beta | 14.28 days | treatment of excess red blood cells Isotope prepared in a nuclear reactor |
Samarium-153 | beta | 1.93 days | used in the treatment of pain associated with bony metastases of primary tumours Isotope prepared in a nuclear reactor |
Yttrium-90 | beta | 64.1 hours | liver cancer therapy Isotope prepared in a nuclear reactor |
Thallium-201 | gamma | 3 days | locating damaged heart muscle Isotope prepared in a cyclotron |
Caesium-137 | beta | 30.2 years | radiotracing to identify sources of soil erosion & depositing, also used in thickness gauging |
Gold-198 | beta | 2.69 days | trace factory waste causing ocean pollution and to trace sand movement in river beds and on ocean floors |
Gadolinium-153 | gamma | 240.4 days | used in X-ray fluorescence and bone density guages for osteoporosis screening |
Zinc-65 | gamma | 244.26 days | used to predict the behaviour of heavy metals in effluents from mining waste water |
Manganese-54 | gamma | 312.2 days | used to predict the behaviour of heavy metals in effluents from mining waste water |
