Radon water, also called radium water or radioactive radon water, is hot mineral water containing radon. It is the most unique type of therapeutic water. It is potable and can be used for bathing, and it has anti-inflammatory effects and can be used to treat endocrine disorders, the peripheral nerve system, gynaecological diseases and urinary disease. It is particularly effective for curing skin diseases. The water of the Tengchong Hot Spring in Yunnan Province contains 209 becquerel/L of radon, which has curative effect on more than 40 kinds of diseases.