Radioactive elements are found everywhere in the environment. Detectable amounts occur naturally in soil, rocks, water, air and vegetation and may be ingested if they enter the food chain, or, inhaled. Inhaled and ingested ...

Throughout their lives, human beings are continually exposed to radiation from terrestrial radionuclides particularly 40K, 238U, 232Th and their decay products. The radiation, usually in the form of gamma rays and alpha ...