Deaths due to the Chernobyl disaster 800 roentgens, twice the normal 50% probability of death dose. The following list is of those directly killed by the explosion and initial radioactivity release, or in the support efforts that followed. Deaths due to the Chernobyl disaster The Chernobyl disaster (, "Chornobylʹsʹka katastrofa", "Chernobyl accident") was considered as one of the worst nuclear disasters in history. It occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the Ukrainian Soviet Socialist Republic, then part of the Soviet Union, now in Ukraine. The scientific consensus on the effects of the disaster has been developed by the United Nations
Effects of the Chernobyl disaster can cause a physiological increase in the rate of pregnancy anomalies, but unlike the dominant linear-no threshold model of radiation and cancer rate increases, it was known, by select researchers who were familiar with both the prior human exposure data and animal testing, that the "Malformation of organs appears to be a deterministic effect with a threshold dose" below which, no rate increase is observed. This teratology (birth defects) issue was discussed by Frank Castronovo of the Harvard Medical School in 1999, publishing a detailed review of dose reconstructions and the available pregnancy data following the Chernobyl accident, inclusive of