David R. Grimes,physicist and cancer researcher at Oxford University. Thirty years has passed since events in Chernobyl, while Japan marks the fifth anniversary of the Fukushima disaster. We need more than ever to have a reasoned discussion on the issues. It is important also to see these disasters in the wider context of energy production: when the Banqiao hydroelectric dam failed in China in 1975 it led to at least 171000 deaths and displaced 11 million people. Our reliance on fossil fuels is particularly costly, not only to the environment but to human health; each year, at least 1.3 million people are estimated to die from air pollution. Shutdown of the plants in Japan has led to not only increased pollution, but rolling blackouts and protests. By contrast, France has for decades produced 75% of its energy through nuclear, and enjoys the cleanest air and among the lowest carbon emissions of any industrialised nature.