The textbook deals with the basics of radioecology, the basic principles of measuring the radionuclide content in the environment. The migration of radionuclides in aquatic ecosystems, soil, atmosphere, plant and animal organisms is considered. The main methods for calculating doses from external and internal exposure are given.

The textbook is intended for students of higher educational institutions of Ukraine majoring in 101 «Ecology and Environmental Protection», and can be useful to a wide range of environmental services.