In day-to-day life, in what areas and articles of daily use does one come across radioactivity? What are the other areas where nuclear energy is used?
Radiation has always been present everywhere in the environment. Every human being is also naturally radioactive as potassium is an essential constituent of body tissues and fluids, and contains а small amount of the radioactive isotope К-40. In а small area of land 40 m х 10 m surrounding а typical house there is contained in the soil down to 1 m depth, 2 kg of uranium, б kg of thorium and 0.8 kg of К-40, all of which are radioactive along with associated radioactive daughter products. Of course these concentrations of U and Th are too low for economic recovery! Not only are radioactive materials like uranium, thorium, radium and potassium present in earth everywhere, radiation is constantly streaming towards earth from outer space in the form of cosmic radiation. Our bodies also contain radioactive С-14, which is produced in the atmosphere by the action of cosmic rays and absorbed by living organisms. In aero plane flights passengers are exposed to higher than normal radiation levels
