It is all explained here "in a calm rational scientific manner". Refs * Japan nuclear threat: The tsunami is the bigger tragedy By David Spiegelhalter, Professor of the Public Understanding of Risk, Cambridge University * Pakistan miners feared dead - for anyone who thought that coal was safe. * Why Fukushima made me stop worrying and love nuclear power - George Monbiot * Jurrassic Park is a triumph for dino theme parks: Build more dinosaur theme parks now! * JEB on some back-of-the-envelope calculations of radiation risk