Environment

Radioactive Cloud Over Europe

European authorities are providing new details about a cloud of mysterious radioactive material that appeared over the continent last month. Monitors in Italy were among first to detect the radioactive isotope ruthenium-106 on Oct. 3. In total, 28 European countries saw the radioactive cloud.

Based on the detection from monitoring stations and meteorological data, the mysterious cloud — which has since dissipated — has been traced to somewhere along the Russia-Kazakhstan border, somewhere in South Russia.

Authorities say the amount of material seen in Europe was small. It was a very low level of radioactivity and it poses no problems for health and the environment in Europe.

But modeling suggests that any people within a few kilometers of the release — wherever it occurred — would have needed to seek shelter to protect themselves from possible radiation exposure.