Radioactivity and life. YK Kudrytski (MD) 1971 Part 20.

Further, the body's response to irradiation depends on the quality conducted; ins dose, duration and spatial distribution of radiation deistviya agent, as well as radio sensitivity of the organism. When opreJ!: Helen combinations of these conditions effect ioniziruyuschei p adpatsii may be pathogenic, causing damage, illness, or be within the physiological norm of reaction, the sst to be harmless, not causing health problems.
BIOLOGICAL SIGNIFICANCE natural background
, Ionizing radiation
Ionizing radiation from natural sources of radiation, I think, is an obligate, a necessary condition for the existence of life on Earth. " Therefore, the study of biological values ​​of natural background radiation is extremely important for understanding its effect on living organisms.
In addition, increased natural radiation background due to artificial sources of ~ creates an environment where no knowledge of the role of natural radiation biologicheskoi extremely difficult to learn and ~ Prices:: b biological effect of additional radiation vozdeistvii from artificial sources.
However, current knowledge on the biological significance of natural background radiation is very limited, due to the very large methodological difficulties ~ during the research
vanii. .
It must first be acquainted with the main natural sources of ionizing radiation. Them for living beings, there are three: the biosphere radioactive substances, radioactive substances in the organisms themselves, and, finally, the cosmic radiation.
Cosmic radiation at ground level is the result of continuous irradiation of the atmosphere the cosmic flow of atomic nuclei, including most of the nuclei of hydrogen atoms - protons, considerably less than the alpha particles and nuclei of heavier elements. These atomic nuclei accelerated in the interstellar electromagnetic fields to speeds prnblizh ayuschihsya the speed of light, and possess enormous energy. They are called primary cosmic rays.
It reached about 30 kilometers from the Earth, most of the primary cosmic rays interact with atoms and molecules of the atmosphere. This raises the so-called secondary cosmic rays, consisting of streams of electrons, positrons, neutrons, protons, mesons, and various
Nogo form of photons. .
Level reaches the earth's surface mostly secondary cosmic rays and nekogoraya part of the primary. The intensity of cosmic radiation at sea level is such that