The ecological assessment of radon concentration in thermal waters of the Talysh in Azerbaijan.

The article presents the results of the first estimated assessments of the radon level in thermal waters of the Talysh region. The investigation of the 9 natural water outputs in the 7 thermal sources allowed determining of radon values changes in the very wide ranges -- from 3,73 up to 93,3 Bq/L. which are typical to groundwater. They are defined as slightly radon. The dependence of radon content on gas composition/ gas saturation of water is noted: relatively low content of radon is typical for nitric water, the highest -- for acidulous water, intermediate value -- for methane water. The rated depth of aquifer does not exceed 2,4 km. According to sanitary-hygienic standards radon content of thermal water of the Talysh, except the watersource Buludul in the Yardymli District, is not dangerous to human health when taking bath and using as a drinking water. In the water of the Buludul radon content exceeds the maximum allowable concentration in more than 1,5 times adopted for a drinking water.