Nuclear and radiation accidents by death toll

There have been more than 20 nuclear and radiation accidents involving fatalities. These involved nuclear power plant accidents, nuclear submarine accidents, radiotherapy accidents and other mishaps.

56 direct deaths (47 accident workers and nine children with thyroid cancer) resulted from the 1986 Chernobyl disaster, and it is estimated that there may eventually be 4,000 extra cancer deaths among the approximately 600,000 most highly exposed people.

Estimates of the total number of deaths potentially resulting from the Chernobyl disaster vary enormously: Thirty one deaths are directly attributed to the accident, all among the reactor staff and emergency workers. A UNSCEAR report places the total confirmed deaths from radiation at 64 as of 2008. The World Health Organization (WHO) suggests it could reach 4,000 civilian deaths, a figure which does not include military clean-up worker casualties. A 2006 report predicted 30,000 to 60,000 cancer deaths as a result of Chernobyl fallout. A Greenpeace report puts this figure at 200,000 or more. A disputed Russian publication, Chernobyl, concludes that 985,000 premature cancer deaths occurred worldwide between 1986 and 2004 as a result of radioactive contamination from Chernobyl.

The Kyshtym disaster, which occurred at Mayak in the Soviet Union on 29 September 1957, was rated as a level 6 on the International Nuclear Event Scale, the third most severe incident after Chernobyl and Fukushima. Because of the intense secrecy surrounding Mayak, it is difficult to estimate the death toll of Kyshtym. One book claims that "in 1992, a study conducted by the Institute of Biophysics at the former Soviet Health Ministry in Chelyabinsk found that 8,015 people had died within the preceding 32 years as a result of the accident." By contrast, only 6,000 death certificates have been found for residents of the Tech riverside between 1950 and 1982 from all causes of death, though perhaps the Soviet study considered a larger geographic area affected by the airborne plume. The most commonly quoted estimate is 200 deaths due to cancer, but the origin of this number is not clear. More recent epidemiological studies suggest that around 49 to 55 cancer deaths among riverside residents can be associated to radiation exposure. This would include the effects of all radioactive releases into the river, 98% of which happened long before the 1957 accident, but it would not include the effects of the airborne plume that was carried north-east. The area closest to the accident produced 66 diagnosed cases of chronic radiation syndrome, providing the bulk of the data about this condition.

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