It is 80 years since the first nuclear weapon test – codenamed Trinity – detonated above the desert in New Mexico. Today the hidden legacy of nuclear bomb tests can still be found in our cells – and is proving surprisingly useful to scientists.

It's in your teeth. Your eyes and your brain too. Scientists call it the "bomb spike" (or "bomb pulse") – and for more than half a century its signature has been present inside the human........

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