Atomic Bomb Casualty Commission hypocenter acute radiation syndrome Midori Naka LD50 polytraumatic sepsis suppresses the white blood cell count radiation poisoning radiation Nagasaki Hiroshima
An estimated 90,000 to 140,000 people in Hiroshima (up to 39 percent of the population) and 60,000 to 80,000 people in Nagasaki (up to 32 percent of the population) died in 1945, though the number which died immediately as a result of exposure to the blast, heat, or due to radiation, is unknown. One Atomic Bomb Casualty Commission report discusses 6,882 people examined in Hiroshima and 6,621 people examined in Nagasaki, who were largely within 2,000 meters (6,600 ft) of the hypocenter, who suffered injuries from the blast and heat but died from complications frequently compounded by acute radiation syndrome (ARS), all within about 20 to 30 days. Many people not injured by the blast eventually died within that timeframe as well after suffering from ARS. At the time, the doctors had no idea what the cause was and were unable to effectively treat the condition. Midori Naka was the first death officially certified to be the result of radiation poisoning or, as it was referred to by many, the "atomic bomb disease". She was some 650 meters (2,130 ft) from the hypocenter at Hiroshima and would die on 24 August 1945 after traveling to Tokyo. It was unappreciated at the time but the average radiation dose that would kill approximately 50 percent of adults (the LD50) was approximately halved; that is, smaller doses were made more lethal when the individual experienced concurrent blast or burn polytraumatic injuries. Conventional skin injuries that cover a large area frequently result in bacterial infection; the risk of sepsis and death is increased when a usually non-lethal radiation dose moderately suppresses the white blood cell count.
