Zirconium radioactive

Zirconium radioactive - isotope of zirconium. Zirconium (Zirconium, Zr) is a chemical element of group IV of the periodic system of D. I. Mendeleev. Serial number 40, atomic weight (mass) 91,22. Radioactive isotopes of zirconium - fission products U235 on slow neutrons. The main isotopes - Zr93 (T = 9,5·10s years), Zr95 (T = 65 days) and Zr97 (T=17 hours). The greatest biological danger Zr95 emitting ' -quanta with a total energy of the collapse of 0,728 MeV and?-particles with an energy 0,364-0,404 MeV. As a result of disintegration Zr95 formed a "child" radioactive isotope Nb95 (T=35 days), is also dangerous ' - and beta-emitter. The share Zr95 in a mixture of instant products division may reach 15% of total radioactivity.
Due to radioactive fallout produce nuclear weapons testing Zr95 detected in the environment and humans. When entering through the respiratory system, the period of the biological half-life Zr95 of light does not exceed 35 days, but Zr95 long delayed in the lymphatic glands. When entering through the gastrointestinal tract, the absorption coefficient is 0,01-0,05%. Basically Zr95 is deposited in the skeleton (30-40%), and less in the liver, kidney, spleen, and sex glands. Effective half-life of the body - 56 days. Zr95 can pass through the placenta to the fetus.
Intravenous Zr95 LD50/30 rats is 7 km mccoury/year With long-term intake were impaired in blood-forming organs (decrease in the number of cells and neutrophils)and lymphoid tissue. Education possible osteosarcoma. In the rat osteosarcoma are formed in 8-12 months after the intravenous administration of 1 - 4 mccoury/g Zr95.
Maximum permissible concentration of Zr95 in the water of open reservoirs - 2·10-8 Curie/l, and in the air of working premises - 3·10-11 Curie/L.