Purpose The projected existence and magnitude of carcinogenic effects ionizing radiation at low doses low-dose rates is perhaps the most important issue in protection today. Studies childhood cancer natural background have potential to throw direct light on this question, into a dose range below few tens mSv. This paper describes studies that been undertaken their context, discusses some proble...

background: the induction of cancer appears to be the most important effect of low-dose ionizing radiation to occur in an exposed population. in developing countries 94% of human radiation is from natural sources. in iran some high altitude regions such as, chaharmahal & bakhtiari has high levels of the natural background radiation (higher than the worldwide average). therefore, investigation o...

ever since studies on uranium miners established the presence of a positive risk coefficient for the occurrence of lung cancer in miners exposed to elevated levels of 222rn and its progeny, there was a great upsurge of interest in the measurement of 222rn in the environment and considerable data is generated on the levels of 222rn in the environment across the worlds and is periodically reporte...

All living organisms are exposed to ionizing radiation comprising cosmic rays coming from outer space, terrestrial nuclides occurring in the earth’s crust, building materials, air, water and foods and in the human body itself. The exposures are constant and uniform for all individuals everywhere including the dose from ingestion of 40K in food. Cosmic rays are, more intense at higher alt...

the aim of this study was to investigate the radioprotective effect of thymol as a natural product against salivary glands dysfunction induced by ionizing radiation in rats. the rats were treated with thymol at dose of 50 mg/kg before exposure to radiation at dose 15gy. salivary gland function was evaluated with radioisotope scintigraphy and then salivary gland to background counts ratio was ca...

The recent developments in studies of TeV radiation from blazars are highlighted and the implications of these results for derivation of cosmologically important information about the cosmic infrared background radiation are discussed.