What is ionizing radiation?
Ionizing radiation (hereinafter - IR) is radiation, the interaction of which with the medium leads to the formation of ions of different signs, that is, to the ionization of the medium (see Figure 1). Such properties are possessed by radioactive radiation, high-energy radiation, x-rays, etc. Visible light and ultraviolet radiation are not classified as ionizing radiation.
According to the type of particles that make up the AI, there are 3 main types of radioactive radiation:
-Alpha radiation - is a stream of alpha particles (nuclei of helium atoms). They are highly ionizing particles that quickly lose their energy when interacting with atoms of matter. For this reason, alpha radiation has a small penetrating power (a path in the substance) and is not able to penetrate even through a layer of ordinary paper or human skin. Alpha particles are dangerous only with internal irradiation of organs and tissues.
-Beta radiation - is a stream of electrons. Due to the lower ionizing ability than that of alpha particles, they can overcome a greater distance in matter (2-3 cm in biological tissue).
-Gamma radiation - is not made up of particles like alpha and beta radiation. It, like the light of the Sun, is an electromagnetic wave propagating at the speed of light. The ionizing power of gamma radiation is low. Penetrating ability is the largest (gamma quanta do not linger in biological tissues).
There is also neutron radiation, but more on that later.
What is neutron radiation?
Neutron radiation is nuclear radiation, consisting of streams of particles with a neutral charge (neutrons). The penetrating power of neutrons is very high due to the absence of a charge and, as a result, a weak interaction with matter. But it is important to note that the nature of the interaction of neutrons with the medium strongly depends on the energy of the particles. For this reason, neutrons are divided into groups depending on their energy. The main ones are thermal and fast neutrons. The energy of fast neutrons is billions of times greater than the energy of thermal neutrons. More means better!?
But not in this case. So, fast neutrons, colliding with a significant number of nucleons (the common name for protons and neutrons in the nucleus), slow down, and slower (thermal) neutrons can “quietly” approach the nucleus and be captured by it, as a result, the element transformation reaction occurs. It was this reaction that paved the way for the creation of a nuclear reactor. At present, thermal neutrons are of great importance not only for the operation of nuclear reactors. They are widely used for obtaining radioactive isotopes, studying the properties of nuclei, structural studies of crystals, studying the dynamics of atoms in solids, the properties of molecules, etc.
Radioactivity - is the spontaneous transformation of atomic nuclei, accompanied by the emission of elementary particles or lighter nuclei. The nuclei subject to such transformations are called radioactive, and the transformation process is called radioactive decay. Radioactivity is not a new phenomenon. It has always existed in the universe. Radioactive materials are part of the Earth, and even man is slightly radioactive, because. Every living tissue contains trace amounts of radioactive substances.
Radiation - is an incomprehensible subject for most people. Radiation is invisible and intangible, which is why a person is ready to assume the worst when it comes to the impact of radiation on health. This fear, in turn, is successfully exploited by unscrupulous politicians, environmentalists and the media, who do not care to explain truthfully and adequately to the population what radiation really is; on the contrary, it is often beneficial for them to create a negative, sinister halo around this phenomenon.
And if you look from a scientific point of view - what is known about the effect of ionizing radiation on the human body?
A living cell is 60–70% water. Therefore, the flow of particles of ionizing radiation, penetrating into the body, interacts primarily with water, which leads to its radiation decomposition - this process is called water radiolysis.
Under the action of radiation, foreign chemical compounds are formed in the cells of living organisms. Radiolysis products "attack" the molecular structures of cells, destroy them, and interrupt the normal course of intracellular processes. As a result, the normal functioning of cells is disrupted, and at certain doses they die. But the cells of the human body have the ability to "heal" radiation damage.
Indeed, a person is constantly exposed to natural radiation, and on average is exposed to 3.95 mSv* per year. In addition, there are regions on Earth where the natural background exceeds the planetary average by several times and dozens of times: these include some areas of France, Finland, Sweden, the Altai Territory, coastal areas of southwestern India, and some resorts in Brazil.