RUSSIA has denied that its nuclear power stations in the north-west of the country were responsible for a mild leak of radiation detected in Scandinavia last week.
Rosenergoatom, the power-plant subsidiary of state-owned nuclear group Rosatom, said its installations near St Petersburg and Murmansk were operating normally.
“Aggregated emissions of all specified isotopes in the above-mentioned period did not exceed the reference numbers. No incidents related to release of radionuclide outside containment structures have been reported,” Rosenergoatom said, according to Tass news agency.
The International Atomic Energy Agency, the UN nuclear watchdog, said late on Saturday it had contacted member states seeking more information “and if any event may have been associated with this atmospheric release”.
The IAEA said it had received evidence from international monitoring systems of “elevated” levels of three radioactive isotopes in the Nordic region.
The IAEA’s technical directorate was notified by the Comprehensive Nuclear-Test-Ban Treaty Organization, which maintains independent monitoring systems around the world, that radioisotopes of caesium and ruthenium had been measured well above normal levels by a facility it runs in Sweden. The isotopes do not occur naturally.
Lassina Zerbo, executive secretary of the CTBTO, wrote on Twitter on Friday that its Swedish monitoring unit had detected three isotopes normally associated with nuclear fission that were “higher than usual levels (but not harmful for human health)”. The message included a map of the possible source of the radiation, stretching from north-western Russia across the Baltic to the North Sea.
Mr. Zerbo later added in a second message: “These isotopes are most likely from a civil source. We are able to indicate the likely region of the source, but it’s outside the CTBTO’s mandate to identify the exact origin.”