MOSCOW, December 8. /TASS/. The inter-departmental panel of inquiry has found no traces of ruthenium-106 in test samples taken at the Mayak Combine in the Chelyabinsk Region.

"Examination of test samples identified no presence of ruthenium-106. The strength of gamma radiation and the intensity of beta rays are at the natural background level," the findings say.

The panel of inquiry exposed no violations in the system of radiation monitoring at Mayak.

Earlier, Greenpeace Russia speculated there might have been a leak of ruthenium-106 from Mayak. The plant’s press-service has said that "no sources have been manufactured from ruthenium-106 at the plant in 2017." Mayak pointed out that no works to extract this isotope from spent nuclear fuel and manufacture sources of ionizing radiation on its basis had been carried out at the plant for many years.

Ruthenium-106 affair

Earlier, Germany’s Federal Office for Radiation Protection (BfS) said it had registered slightly elevated levels of ruthenium-106 in the air on September 29 - October 3. BfS stated the concentration of the isotope was very insignificant and posed no threat to health. Also, German specialists said they were certain the higher levels of ruthenium-106 in the air were not due to an incident at a nuclear power plant. A short while later BfS speculated that a leak from a facility in the Southern Urals might have been the source of the isotope.

The Russian weather watching service Rosgidromet reported a greater than usual presence of ruthenium-106 at two monitoring stations in the Chelyabinsk region (Argayash and Novogorny) on September 25 - October 1. Ruthenium-106 is used for radiation therapy. Also, it may be emitted in the process of recycling nuclear fuel.

The Russian state atomic energy corporation Rosatom said it found no traces of ruthenium-106 in air samples taken at different sites in Russia except for those provided by one monitoring point in St. Petersburg. Rosatom also said that Russia’s nuclear power industry enterprises cannot be regarded as sources of the isotope. Rosatom quoted IAEA data showing that in the same period of time the level of ruthenium-106 in Romania was 145,000 microbecquerels per one cubic meter, in Italy, 54,300 microbecquerels, and in Ukraine and Slovenia, 40,000 and 37,000 microbecquerels per one cubic meter respectively.