Over the years, published estimates of the number of premature deaths from radiation released following the 1986 Chernobyl disaster have ranged from 100 to over a billion, many of them based on little more than hunches. Chernobyl had complex and profound consequences for millions of people, but radiation is easy to measure and its impact on human health has been extensively researched. The consensus of mainstream science, as reflected in reports by the UN Chernobyl Forum of experts from the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), other UN agencies and national experts from the countries most directly concerned, is that up to 4,000 premature radiation-related deaths can be expected to occur over the 60 years following the accident from among a population of 7 million in the affected areas of Belarus, Ukraine and Russia. These deaths are tragic, but they are likely to be dwarfed many times over by the increased deaths from heart disease and cancer resulting from additional atmospheric pollution caused by the substitution of planned nuclear power stations by fossil fuel generation around the world as a result of the accident, and from the long-term impact of the resulting acceleration of climate change.