Main Sources of Ionizing Radiation and Its Impact on the Population

Abstract

All sources of ionizing radiation (IR) of human exposure are divided into natural and industrial. Natural sources of radiation are the main sources of human exposure. They include cosmic rays and radiation from natural radionuclides contained in the Earth's crust and atmosphere. Among radionuclides of natural origin, potassium-40 and radionuclides arising from the decay of natural radioactive uranium-238 and thorium-232 are the most important. Potassium, uranium, and thorium present in the earth's crust, when disintegrating, become sources of radiation and form the background external radiation of a person, and entering the body with air, water, and food - internal background radiation. The situation in Ukraine is typical for most countries of the world, although the levels of population exposure from natural sources are somewhat higher than the world average. Industrial sources include sources of both natural origin and those created by man, if they are purposefully used in industrial, scientific, medical and other spheres of human activity with the aim of obtaining a certain benefit. Human exposure to industrial sources can occur in production conditions (professional exposure of workers) and in the living environment. Under normal operating conditions, artificial radiation sources are fully controllable, and exposure from them is predictable. Among all industrial sources of radiation of the planet's population, X-ray diagnostic procedures rank first in terms of dose. A special place is occupied by the exposure of the population and personnel as a result of radiation accidents. Dozens of radiation accidents occur every year in the world, accompanied by the exposure of a small number of people. In some cases, individual radiation doses exceeded several Sieverts and even led to the death of people. The worst radiation accident in terms of the number of people exposed to accidental radiation is Chernobyl. The levels of exposure of a significant part of the population of Ukraine by man-made and enhanced sources of natural origin are determined by certain geological characteristics of the territories. Ensuring radiation safety and anti-radiation protection should be a priority when using sources of ionizing radiation in practice.