Some might say that there's an ongoing war to determine the answer to this question.
Edit: but to be clear, I am not part of those "some," and believe Ukraine is Europe! I just don't know the relative scales of Sellafield and Chernobyl in terms of toxicity.
Russia is also Europe, in the traditional sense. Before the Cold War, this was never in doubt. The ruler was literally a "Caesar", elites spoke French and German, holidayed on the French Riviera, and bickered with other European powers in the Great Game.
The elites were trying to fit in into that world extremely hard, but the ruling method was always самодержавие.
Well, until WWI that was largely the ruling method of choice across the entire continent, eh...
It's an interesting question whether Chernobyl or Sellafield are more toxic, especially with all the additional toxic waste that's send to Sellafield all the time.
both are toxic enough
My imagination hears the protesters yell Toxinough! Toxinough!