Airborne radioactivity was detected in Europe during autumn 2017, starting from the last days of September. The source is widely suspected to be in Russia; the Russian government, however, denies that any nuclear mishaps occurred that could have caused the radiation spike. The radioactive isotope detected was ruthenium-106; across Europe, it was found to be in small quantities (from microbecquerels to a few millibecquerels per cubic metre of air), not significant for the health of the population far away from the source.[1][2][3] It is estimated, however, that the radiation released posed a danger to any employees or residents within several kilometers of the currently unknown source.
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