NATURAL BACKGROUND RADIATION AND ENVIRONMENTAL EXPOSURE

This scientific publication examines natural background radiation as a continuous source of human exposure to ionizing radiation. It provides an overview of the principal natural radiation sources, including cosmic radiation, terrestrial radionuclides, naturally occurring radioactive materials (NORM), and radon and its decay products. Particular attention is given to environmental exposure pathways, external and internal radiation exposure, and the contribution of naturally occurring radionuclides such as potassium-40 (K-40), uranium-238 (U-238), and thorium-232 (Th-232) to human radiation dose. The publication discusses fundamental principles of radiation dosimetry, absorbed dose, equivalent dose, effective dose, environmental monitoring, and radiological assessment. It also considers geographical and geological variations that influence natural background radiation levels and individual exposure. The objective is to provide a scientific and educational reference for understanding environmental radioactivity, evaluating natural radiation exposure, and supporting research and practical applications in radiation protection, nuclear safety, and environmental health.