Radon is a radioactive gas that naturally forms in the environment. It is a product of uranium's radioactive decay which makes it extremely toxic. Radon can remain in the soil, move from the soil to the air or enter groundwater. It is more common in some areas of the United States. Besides being a toxic decay product, radon has several applications, some of them rather surprising.
Identification
Radon is a gaseous and highly radioactive element that, in its gas form, is colorless, odorless and tasteless. Radon is nine times denser than air and therefore the heaviest known gas. Radon is a single atom gas and because of this, its atoms easily penetrate common materials such as paper, leather, plastic bags, paints, gypsum board, concrete, mortar, wood paneling and insulation materials. Radon can dissolve into water and other organic solvents and it can form highly electronegative materials with other molecules. Radon is a noble gas and you can find it in two natural isotopic forms. Radon-220 is a natural product of thorium-232 breakdown and radon-222 is a natural product of uranium-238 breakdown. Radon-222 is the form of radon you most often find in the environment.
Exposure
Inhalation and ingestion are the two most common ways for you to be exposed to radon. You can find radon in igneous rocks and soils, groundwater, well water or building materials used either in your living or working space. After entering a space, radon changes into its breakdown products. These breakdown products are radioisotopes of polonium, lead and bismuth that quickly attach to other airborne materials, such as dust, which make the inhalation of radon easier.
Risks
Radon is the second leading cause of lung cancer in the United States after smoking. According to the Environment Protection Agency (EPA) and the Surgeon General's Office, radon causes more than 20,000 lung cancer deaths and costs the U.S. economy over $2 billion in direct and indirect health cost every year. The EPA recommends a base level of 4 pCi/L of radon, but almost one in three homes tested in seven different states and on three Indian reservations have a radon level higher than that. If you live in a home with radon level higher than 4 pCi/L, you are exposed to more than 35 times more radiation than if you were living next to a radioactive waste site. And if you are a student going to school eight hours a day and 180 days in a year at a school with radon levels over the base level, you are exposed to 10 times as much radiation as if you were spending your time at the edge of a nuclear power plan. Several scientists agree that radon, even at base level, has a one in 100 risk of death and, therefore, there is no safe level of radon gas.
Health Uses
Since the early 1950's, unused gold and uranium mines have been used as health mines and spas. When the health mines and spas first opened, the risks associated with radon were not known, but still today hundreds of people visit these radon spas every summer. Many of the visitors are Amish and Mennonites and they come to the mines and spas to live surrounded by radioactive radon gas, bath in radioactive water and drink radioactive water to improve their health. Radiation levels in the mines and spas can reach 175 times the federal base level, but the visitors claim that the radon mines and spas offer a cure for rheumatoid arthritis, multiple sclerosis, depression and cataracts. Some physicians even recommend these mines and spas for their patients.
Other Uses
Besides health mines and spas, radon is used to study atmospheric transport and to explore petroleum and uranium. Because radon decays rapidly and disappears quickly in the air, radon gas is used in hydrologic research to study interactions between ground water and streams. This finding has led to studies of concentration of radon gas in streams that indicate there is an outlet for groundwater in the stream. Scientists have also found that radon concentrations are increased or are quickly changing around faults and possible earthquake locations, so radon gas can be used to predict earthquakes. In addition, radon can initiate and influence chemical reactions, as well as be used to study surface reactions and detect leaks.