Roshydromet's data on isotope contamination with ruthenium-106 allow us to conclude that the dose that could have been received by a person is 20 thousand times less than the maximum permissible annual dose and does not pose any danger to human health and life.
The first data on the increased values of the volume activity of Ru-106 in the atmosphere was recorded simultaneously in the countries of Western Europe, in Tatarstan, Volgograd and the Southern Urals at the same levels (10-20 mBq / m3). Extremely high concentrations of Ru-106 in the atmosphere were recorded in Slovakia (29-30.09.2017) and in Romania (September 30, 2017), which are located at a distance of about 3,000 km from FSUE “Mayak Production Association”.
The atmospheric pollution by the isotope Ruthenium-106, indicated in the report of Roshydromet, is not related to the activities of the FSUE Mayak Production Association.
Ruthenium-106 can enter the atmosphere in the following cases:
1. In case of violation of the hermetic sealing of the "fuel rod" shell in a nuclear reactor or during the radiochemical processing of nuclear fuel. The option is not possible in this case, since it would have resulted in the emissions into the atmosphere of dozens of other fragmentation radionuclides, which would have been recorded by the radiation monitoring services.
2. In case of production of new sources, the use of existing or recycling of spent ionizing radiation sources on the basis of ruthenium-106. A typical source made of ruthenium-106 has an activity of about 1-10 Ci. With a complete destruction of such a source, the measured concentrations of ruthenium-106 in the atmosphere could be recorded at a distance of up to 500 km, and an increased radiation background and strong radioactive contamination of the atmosphere would be recorded at the site of depressurization of the source.
In 2017, there was no production of the ruthenium-106 sources at FSUE “Mayak Production Association”, emissions to the atmosphere were in the usual regulatory values. Radiation background is normal.
We additionally inform that we haven’t done the separation of ruthenium-106 from the spent nuclear fuel (and have not produced on its basis the sources of ionizing radiation) in our company for many years now."
Thus, FSUE “Mayak Production Association” is not a source of the increased ruthenium-106 content in the atmosphere.