Possible positive effects of chronic low-dose ionizing radiation on human life-span in Talysh, Azerbaijan

Radiation hormesis is the hypothesis that low doses of ionizing radiation (within the region of and just above natural background levels) are beneficial, stimulating the activation of repairing mechanisms that protect against disease, that are not activated in absence of ionizing radiation.The paper describes research results supporting hormesis through exposure to low-dose ionizing radiation conducted in the Talysh region of Azerbaijan.According to the International Committee on Radiation Protection, 40-75% of total human exposure to natural radioactive sources comes from radon and its decay products.Radiometric studies covered five districts of the Talysh region: Masalli, Lankaran, Astara, Yardimli and Lerik.The volume activity of radon in residential areas was measured with radon Scout and radon Scout Plus radiometers from SARAD.Based on the obtained results, maps of the distribution of radon volume activity are constructed separately for each region.According to this map, the Lerik district, known for its long-lived inhabitants, is characterized by a relatively high level of radon.The ECG (electrocardiograph) of cardiac activity is written in the modern cardiograph Cardi Max Fx 8222 produced by the Japanese company Denshi Fukuda.The results of the research showed that there is a certain correlation between the level of radon in homes and life expectancy.According to the current regulatory document, the indoor radon volume activity should not exceed 200 Bq/m³.Based on research results, in villages where centenarians are living, the level of indoor radon varies between 100-200 Bq/m 3 , averaging 150 Bq/m 3 .