A solution to the mystery surrounding the detection of radioactivity in various countries of Europe - including Greece - was provided by the French Nuclear Safety Institute (IRSN).
French scientists see a nuclear accident in Russia or Kazakhstan as the cause of radioactivity readings in various regions of Europe, including Greece.
In particular, the French Nuclear Safety Institute estimates that ruthenium 106 was the product of an accident at a nuclear waste management facility at either a nuclear medicine center in Russia or Kazakhstan and that it is by no means a nuclear reactor accident.
The estimate of the French scientists is that the initial leak was between 100 and 300 terra becquerels, adding that if this had happened in France, they would have called for the evacuation of areas several kilometers from the point of leakage, although they claim that the existence of ruthenium in the skies of Europe has had no impact on the health of Europeans.
French scientists have delineated the area in which the nuclear accident may have occurred by studying all the weather data of the period when ruthenium 106 was detected in Europe.
The Russians, however, according to the director of the French institute, have said they are ignorant of such an incident on Russian territory, and the authorities of Kazakhstan have yet to reply.