Chernobyl disaster
4,000 fatalities[1][2] – Chernobyl disaster, Ukraine, April 26, 1986. 56 direct deaths (47 accident workers and nine children with thyroid cancer) and it is estimated that there were 4,000 extra cancer deaths among the approximately 600,000 most highly exposed people.
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Kyshtym disaster
The Kyshtym disaster, which occurred at Mayak in the Soviet Union, 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."[11] 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,[12] 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.[12] 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.[13] The area closest to the accident produced 66 diagnosed cases of chronic radiation syndrome, providing the bulk of the data about this condition.[14]
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Windscale fire
33+ cancer fatalities (estimated by UK government)[15][16] – Windscale, United Kingdom, October 8, 1957. The Windscale fire resulted when uranium metal fuel ignited inside plutonium production piles; surrounding dairy farms were contaminated.[15][16]
Other accidents
17 fatalities – Instituto Oncologico Nacional of Panama, August 2000 – March 2001. Patients receiving treatment for prostate cancer and cancer of the cervix receive lethal doses of radiation.[17][18]
13 fatalities – Radiotherapy accident in Costa Rica, 1996. 114 patients received an overdose of radiation from a Cobalt-60 source that was being used for radiotherapy.[19]
11 fatalities – Radiotherapy accident in Zaragoza, Spain, December 1990. Cancer patients receiving radiotherapy; 27 patients were injured.[20]
10 fatalities – Soviet submarine K-431 reactor accident, August 10, 1985. 49 people suffered radiation injuries.[21]
10 fatalities – Columbus radiotherapy accident, 1974–1976, 88 injuries from Cobalt-60 source.[18][22]
9 fatalities – Soviet submarine K-27 reactor accident, 24 May 1968. 83 people were injured.[18]
8 fatalities – Soviet submarine K-19 reactor accident, July 4, 1961. More than 30 people were over-exposed to radiation.[20]
8 fatalities – Radiation accident in Morocco, March 1984.[23]
7 fatalities – Houston radiotherapy accident, 1980.[18][22]
5 fatalities – Lost radiation source, Baku, Azerbaijan, USSR, October 5, 1982. 13 injuries.[18]
4 fatalities – Mihama Nuclear Power Plant accident, August 9, 2004. Hot water and steam leaked from a broken pipe (not actually a radiation accident).[24]
4 fatalities – Goiânia accident, September 13, 1987. 249 people received serious radiation contamination from lost radiotherapy source.[25]
4 fatalities – Radiation accident in Mexico City, 1962.
3 fatalities – SL-1 accident (US Army) 1961.
3 fatalities – Samut Prakan radiation accident: Three deaths and ten injuries resulted when a radiation-therapy unit was dismantled, February 2000.[26]
2 fatalities – Tokaimura nuclear accident, nuclear fuel reprocessing plant. Japan, September 30, 1999.[27]
2 fatalities - Meet Halfa, Egypt, May 2000; two fatalities due to radiography accident.[28]
1 fatality – Mayapuri radiological accident, India, April 2010.[26]
1 fatality – Daigo Fukuryū Maru March 1, 1954
1 fatality – Louis Slotin May 21, 1946
1 fatality – Harry K. Daghlian, Jr., August 21, 1945 at Los Alamos National Laboratory in New Mexico.
1 fatality – Cecil Kelley criticality accident, December 30, 1958 at the Los Alamos National Laboratory.[29]
1 fatality - Operator error at Wood River Junction nuclear facility, 1964, Rhode Island, Robert Peabody dies 49 hours later
1 fatality – Malfunction INES level 4 at RA2 in Buenos Aires, Argentina, 1983, operator Osvaldo Rogulich dies days later.
1 fatality - San Salvador, El Salvador, 1989; one fatality due to violation of safety rules at 60Co irradiation facility.[28]
1 fatality - Soreq, Israel, 1990; one fatality due to violation of safety rules at 60Co irradiation facility.[28]
1 fatality - Tammiku, Estonia, 1994; one fatality from disposed 137Cs source.[28]
1 fatality - Sarov, Russia, June 1997; one fatality due to violation of safety rules.[28]
