In Traditional Medicine

• Radon, namely a variation or isotope called Radon 222, is used in radiation therapy since it is generally stable. Auto-immune diseases such as arthritis, and degenerative diseases such as cancer, turn the immune system against the body. This type of therapy works against these types of diseases by exposing patients to low doses of radiation which suppresses the immune system. Likewise, a procedure called "radon seeding," whereby radon is encased in gold or glass tubes and then implanted near a tumor, is used as a part of radiotherapy as well as on its own to treat different kinds of tumors. This method of treatment has fallen out of use, as radon, like other radioactive gases, is toxic and even fatal, with the fatal dosage varying from person to person.
  
  

In Homeopathic Medicine

• For ages, people have been bathing in hot springs to cure a number of ailments, as these springs typically exhibit a high level of radon. In the 1950s, "health mines" began to cater to those suffering from various diseases by offering them exposure to the radon gases and radioactive waters naturally present in the mines. As of 2011, people still frequent these mines in an effort to cure debilitating diseases under the belief that chronic low doses of radiation will work in the same way that Radon 222 works in radiation therapy. This belief, called radiation hormesis, has become highly controversial and is contended by medical professionals. It has yet to be fully substantiated by medical science.
  
  

In Hydrology

• Radon particles can also have the opposite effect, in that they can move downward through the soil and into the groundwater. Hydrology is the study of the various properties of water such as movement, distribution and quality, and the relationship of these properties on the environment. Radon has been used to the advantage of hydrologists who are seeking to study the relationships between streams and groundwater. Due to its rapid loss to air, significant concentrations of radon in streams typically indicate local sources of groundwater. This information is used in ways from creating surface maps of radon in groundwater to predicting when and where radon will be released.
  
  

In Atmospheric Science

• Soil naturally contains concentrations of radon. These radon particles flow towards the surface as barometric pressure falls and reverse as barometric pressure rises. This is used by atmospheric scientists seeking to study atmospheric processes and their effects to track changes in barometric pressure and, to a limited degree, the flow of air masses and the intervals between rainfall. Because radon is an unstable element prone to spontaneous decay and since it has a relatively low half-life of about 3 to 4 days, using radon in this manner is often unreliable and still contended by experts.
  
  

In Geology

• Radon has been used for a number of purposes by geologists. Since concentrations of radon in the soil are higher over faults, radon has been suggested as a means of pinpointing underground faults and as a way to map geothermal gradients or the rate at which Earth's temperature rises at lower depths. Radon levels have also been used in a limited degree to predict earthquakes. The early stages of an earthquake cause vibrations in the rocks containing radon, causing microcracks that release the radon into the groundwater that surges through the cracks due to increased water pressure. The water causes the radon to break down faster. The water is then carried away from the rocks but, as the vibrations die down, the water returns. The newly saturated water then escapes to the surface through the microcracks, causing higher levels of radon on the surface.