A cloud of radioactive pollution spread over Europe after a possible “accident” at a nuclear facility in Russia or Kazakhstan, French nuclear safety officials confirmed on Friday.
France’s nuclear safety institute, IRSN, picked up faint traces of ruthenium 106, a radioactive nuclide that is produced when atoms are split in a nuclear reactor and which does not occur naturally, in three of its 40 monitoring stations late September.
Faint traces were also detected in Germany, Austria, Italy and Switzerland.
There has been no impact on human health or the environment in Europe, a French official stressed, but he added that detection of such a cloud was “absolutely not normal”.
IRSN, the technical arm of the French nuclear regulator, said in a statement it could not pinpoint the location of the release of radioactive material but that based on weather patterns, the most plausible zone lay south of the Ural mountains, between the Urals and the Volga river. This could indicate Russia or possibly Kazakhstan, it said.
Graphic: Path of the cloud
At the source of the leak, the quantity of ruthenium 106 released was “major”, between 100 and 300 teraBecquerels, it said, adding that if an accident of this magnitude had happened in France it would have required the evacuation or sheltering of people in a radius of “a few kilometres around the accident site”.
But it said that the probability of importation into France of foodstuffs, notably mushrooms, contaminated by ruthenium 106 near the site of the accident was extremely low.
At a glance | Nuclear incidents and accidents
Measurement from European stations showed high levels of ruthenium 106 in the atmosphere of the majority of European countries, at the beginning of October, with a steady decrease from Oct. 6 onwards.
France picked up traces of the pollution in monitoring stations of Seyne-sur-Mer, Nice and Ajaccio from September 27 to October 13, and has not detected anything since.
Jean-Christophe Gariel, director for health at the…