# The Impact of Tritium in the Environment
## 6 Summary  
Once released into the environment, tritium is distributed globally owing to its half-life and residence time; therefore, the consequences of its exposure should be considered to ensure the protection of the public and the environment from radioactive discharges. Despite improvements in the operational practices of nuclear plants and in waste management and disposal, several problems remain. The main problems are as follows:  
* An increased content of tritium in the biosphere at about 20 times that at the beginning of the nuclear era. * Insufficient study of the radiobiological impact of tritium: the impact of incorporated tritium on living organisms is estimated to be three times higher than that of \({}^{137}\)Cs, while the local impact (for DNA molecule) may be 300 times higher. * Uncertainty of safe concentrations: world standards for the tritium content in drinking water differ by more than 700 times (from 100 to 76,100 Bq\(\cdot\)dm\({}^{-3}\)), and scientifically based estimates differ by 600,000 times. * Extremely high migration capacity of the aqueous form of tritium: the rate constant of the isotopic exchange of protium for tritium in water is estimated at (1.5 \(\pm\) 0.5) \(\times\) 10\({}^{-4}\) s\({}^{-1}\). * The crucial role of water for living organisms: there is no indication of the biomagnification of tritium in terrestrial systems. * The large amount of contradictory data on tritium accumulation in living organisms. * The fact that there are practically no ways to clean liquid discharges and gaseous emissions of tritium from nuclear facilities; existing methods of hydrogen isotope separation require significant energy costs. * The metastability of tritium emissions from nuclear reactors, which cause a paroxysmal nature of tritium emissions and create obstacles in predicting its distribution in the environment. During the nuclear power cycle, tritium generated in nuclear units and contained in spent fuel may be released into the environment. Present tritium emissions into the biosphere have reached equilibrium, reflecting the exhaustion of the current technological capabilities of nuclear power. Future development of thermonuclear synthesis could increase the tritium inventory by several orders of magnitude, and tritium would thus become the Achilles' heel of fusion. However, despite widespread optimism (since the 1950s, when the first research began), significant obstacles between today's understanding of nuclear fusion processes, technological capabilities, and practical applications of nuclear fusion have not yet been overcome. The supply of nuclear fission energy mainly depends on the limitation of uranium resources. The reserves of uranium-235 used in thermal neutron reactors can be used by humans for decades (according to the 2024 reserve to production ratio), but the plutonium-239 used in fast neutron reactors is converted from uranium-238, and according to the reserves of uranium-238, it can provide humans with nuclear fission energy for thousands of years. This also applies to thorium fuel. So, the timetable for the use of nuclear fusion energy does not depend on changes in the existing energy structure but on the maturity of nuclear fusion technology, as well as economic, social, political, and other factors. Humans have enough time to obtain satisfactory answers in the utilization of nuclear fusion energy. In nuclear fusion reactors, the production or breeder of tritium is used for the continuous use of fusion energy, that is, the production or breeder of tritium is used to consume tritium to produce continuous energy rather than for other products. In addition, the production capacity of tritium can be adjusted through the rational design of nuclear fusion reactors to ensure a reasonable allocation between continuous fusion energy production and minimum storage capacity.