Its nucleus consists of one proton and two neutrons, making it three times as heavy as a hydrogen nucleus with its one proton and one-and-a-half times as heavy as deuterium which contains one proton and only one neutron. Tritium would no longer exist in our environment if cosmic radiation produces it in the atmosphere in very small amounts.
The half-life of the unstable tritium nucleus is of This comparatively fast disappearance means that very little tritium can accumulate in any place. Tritium, like hydrogen, is particularly mobile. It can combine with oxygen to form tritiated water and therefore has the ability to get easily into the human body thanks to the water cycle.
Once inside the body, tritium can lead to internal exposure though the element is eliminated very quickly. Its biological half-life of 10 days is far shorter than the Only one tritium nucleus out of will decay while still inside the human body.
Because of the low emission energy, the beta electron trajectory will not exceed a few microns inside the body. Tritium therefore has a particularly low radiotoxicity dose factor. The World Health Organization, WHO considers that the limit of acceptability of water containing tritium is 10, Becquereles per liter.
This limit is protective. One should drink 2 liters of such water everuyday a day for a year to be exposed to a dose of 0. In February , during the unloading operation of nuclear fuel unloading, tritium contaminated water above normal levels spread under the Indian Wells nuclear power plant near New York. According to the Nuclear Regularity Commission - the US safety authority - this leak did not pose a threat to the environment.
Indeed, tritium the tritium radoactive toxicity particularly little small. Once spilled into the Hudson, the radioactive water was so diluted that tritium became virtually undetectable. The same goes for tritiated effluents from the La Hague plant in France. In biology, tritium is often used to mark hydrogen and thus in the study of metabolism.
As a liquid, tritium moves easily through the environment just like water. Tritium occurs naturally in the environment in very low concentrations. In the mids and early s, man-made tritium was widely dispersed during the above-ground testing of nuclear weapons. The quantity of tritium in the atmosphere from weapons testing peaked in and has been decreasing ever since. Today, sources of tritium include commercial nuclear reactors and research reactors, and government weapons production plants.
Tritium may be released as steam from these facilities or may leak into the underlying soil and ground water. Tritium can also enter the environment from improper handling, or illegal disposal of exit signs in municipal landfills. As water seeps through landfills, it can spread the tritium from the broken signs.
Regulations require that tritium exit signs be returned to a licensed facility for disposal. Tritium emits a very weak beta particle. People are exposed to small amounts of tritium every day, since it is widely dispersed in the environment and in the food chain. Tritium primarily enters the body when people swallow tritiated water, inhale tritium as a gas in the air, or absorb it through their skin.
Once tritium enters the body, it disperses quickly and is uniformly distributed throughout the body. Since tritium is almost always found as water, it goes directly into soft tissues and organs. Tritium is excreted through the urine within a month or so after ingestion. Organically bound tritium tritium that is incorporated in organic compounds can remain in the body for a longer period. Skip to main content.
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