Environmental impact of nuclear power 20 other US nuclear plants in recent years, has kindled doubts about the reliability, durability, and maintenance of aging nuclear installations in the United States. Tritium is a radioactive isotope of hydrogen that emits a low-energy beta particle and is usually measured in becquerels (i.e. atoms decaying per second) per liter (Bq/L). Tritium can be contained in water released from a nuclear plant. The primary concern for tritium release is the presence in drinking water, in addition to biological magnification leading to tritium in crops and animals consumed for food. Tritium, the mass 3 isotope of hydrogen is deliberately created
Isotope persisted down to the present because their rate of decay is so slow (e.g. uranium-238 and potassium-40). Post-primordial isotopes were created by cosmic ray bombardment as cosmogenic nuclides (e.g., tritium, carbon-14), or by the decay of a radioactive primordial isotope to a radioactive radiogenic nuclide daughter (e.g. uranium to radium). A few isotopes are naturally synthesized as nucleogenic nuclides, by some other natural nuclear reaction, such as when neutrons from natural nuclear fission are absorbed by another atom. As discussed above, only 80 elements have any stable isotopes, and 26 of these have only one stable isotope. Thus, about two-thirds