Which of the following is a naturally occuring radioactive substance in the body in small quantities?
Sources of radiation exposure are: Natural sources and Manmade sources. The natural sources include cosmic rays, environmental (terrestrial and atmospheric) radiation, internal radiation (Potassium - 40 & Carbon -14) Man-made Radiation: Medical and dental: X rays, radioisotopes Occupational exposure Nuclear Misc: TV, Radio-active dial watches, Luminous markers Park's Textbook of Preventive and Social Medicine, 25th Edition, Pg 803
Radium 226
Bismuth 60
Iodine 131
Potassium 40
Environment and health