Russian radiation leak: everything you need to know

'Extremely high' levels of a radioactive isotope were discovered in parts of Russia in September. But where did it come from? And is it dangerous?Russia reports radioactivity 986 times the norm after nuclear accident claimRussia's meteorological service has confirmed that "extremely high" concentrations of a radioactive isotope, ruthenium-106, were found in several parts of the country in late September. Ru-106 is a decay product from nuclear reactions: the initial fuel is typically uranium or plutonium, and this splits into smaller nucleii, which decay through a series of different radioactive elements. Most of the isotopes in the sequence have very short half-lives, meaning they exist for only a few seconds or minutes, but Ru-106 has a half-life of just over a year. That means if it leaks, it sticks around long enough to be detected. Continue reading...