Radioactivity can be detected at different levels in almost all objects all over the world, including the human body. This omnipresence of naturally occurring radioactivity is of immediate and crucial concern to people who work in the nuclear industry, to state and local authorities responsible for environmental protection and control of nuclear weapons, and to researchers as physics (e. g., interaction in scientific and technological disciplines, such of radiation with matter), chemistry (e. g., management of radioactive wastes), biology Ce. g., radiation bioeffects and risks), ecology (e....