ESTIMATED CASUALTIES AND DESTRUCTION CAUSED BY THE ATOMIC BOMBS DROPPED ON THE EFFECTS OF NUCLEAR HIROSHIMA AND NAGASAKI IN 1945 WEAPONS ON HUMAN On 6 August 1945 a 13 kiloton atomic bomb exploded over Hiroshima, Japan. This was followed on 9 August by the explosion of a 21 kiloton bomb over Nagasaki. To date, these have been the only times a nuclear weapon has been used in armed conflict. The following figures reflect the scale of the casualties and damage that resulted from the explosions. HEALTH INFORMATION NOTE NO. 1 Deaths: Hiroshima: 100,000 – 140,000 killed* Nagasaki: 60,000 – 70,000 killed* THE IMMEDIATE AND THE EFFECTS AND Total area destroyed by heat, blast and fire: Hiroshima: 13 sq km (including 4 sq km completely destroyed by a firestorm) LONG-TERM HEALTH CASUALTIES OF THE HEAT Nagasaki: 6.7 sq km CONSEQUENCES OF AND BLAST WAVES NUCLEAR WEAPONS Impact on medical services in Hiroshima: Heat casualties: The earth below the 270 out of 300 doctors killed or injured The atomic bombings of Hiroshima and epicentre of the blast would be heated to 1,654 out of 1,780 nurses killed or injured Nagasaki in 1945 and medical studies a temperature of approximately 7000°C, 112 out of 140 pharmacists killed or injured conducted since that time have shown the which would vaporize all living things National Nuclear Security Administration / Nuclear SecurityNational Administration Office Site Nevada type of immediate and long-term health in that area. Tens of thousands of those * Number of deaths attributable to the atomic bombs by the end of 1945. consequences that can be expected in people who will not have been vaporized Estimates are based on various surveys conducted by the Japanese authorities and by scholars between August 1945 and August 1946. the event of even a limited use of nuclear would be burnt, with most people weapons. The following describes the suffering horrific full thickness skin burns. health effects and casualties that could be Severe burns could occur up to 3 km SUMMARY expected from only one 10 to 20 kiloton from the blast. In addition, many people The explosion of a nuclear weapon nuclear weapon (the size of the bombs looking in the direction of the explosion SOURCES: releases a combination of heat, that destroyed Hiroshima and Nagasaki) would suffer temporary flash blindness British Medical Association, The Medical Effects of Dr. Marcel Junod, “The Hiroshima Disaster”, The United States Strategic Bombing Survey, The blast waves and radiation. These detonated at an altitude of 1 km above a for up to 40 minutes or even permanent Nuclear War, John Wiley & Sons, Chichester 1983. International Review of the Red Cross, 1982. Effects of Atomic Bombs on Hiroshima and Nagasaki, forces have the potential to kill and densely populated area1. eye damage, including retinal burns and Chairman’s Office, 30 June 1946, Washington, United injure massive numbers of people, scarring affecting the visual field, from The Committee for the Compilation of Materials on Lachlan Forrow, M.D., Victor W. Sidel, M.D., Jonathan E. States Government Printing Office, 1946. The intense fireball generated in the looking at the fireball with the naked eye. Damage Caused by the Atomic Bombs in Hiroshima Slutzman, B.S.E., Medicine and Nuclear War: Preventing to obliterate homes, buildings and instant that the nuclear weapon explodes and Nagasaki, Hiroshima and Nagasaki: the Physical, Proliferation and Achieving Abolition, September 10, infrastructure, and to have severe Medical, and Social Effects of the Atomic Bombings, Basic 2007, Paper prepared for “Nuclear Weapons: The Final would trigger the release of heat, blast Blast casualties: The fireball and flash Books Inc, New York, 1981. Pandemic – Preventing Proliferation and Achieving consequences for the environment. waves and radiation. heat would immediately be followed Abolition,” an International Conference Sponsored by by blast pressure waves travelling at International Physicians for the Prevention of International Physicians for the Prevention of Nuclear Whether the explosion is a result supersonic speeds. People would be Nuclear War, Zero is the only option. Four medical and War and the Royal Society of Medicine, London, killed or severely injured by collapsing environmental cases for eradicating nuclear weapons, October 3–4, 2007. of a missile strike during an armed 1 It should be noted that this is a very small weapon by modern 2010. conflict, an act of terrorism or an standards. Many nuclear weapons today are up to 30 times larger. homes, falling buildings or flying debris, accidental detonation, it will have a major impact on the health of those directly affected and on the capacity to provide assistance to survivors in the immediate aftermath. International Committee of the Red Cross 19, avenue de la Paix 1202 Geneva, Switzerland T +41 22 734 60 01 F +41 22 733 20 57 E-mail: [email protected] www.icrc.org For further information, visit A hospital in Hiroshima after © ICRC, February 2013 www.icrc.org/eng/war-and-law/weapons/nuclear-weapons 4132/002 02.2013 the August 1945 bombing ICRC Archives Info Note #1 EN The effects of nuclear weapons on health.indd 1 22/05/2013 07:12 or from being thrown through the air. THE CASUALTIES AND Many of those who survive the heat Even if people survived the immediate THE EFFECT ON MEDICAL These consequences were highlighted Injuries would include ruptured organs, LONGER TERM EFFECTS and blast effects of a nuclear explosion dangers or exposure to radiation, they TREATMENT AND by Marcel Junod, a delegate of the compound fractures, fractured skulls OF RADIATION AND would fall victim to radiation sickness in would face an increased risk of developing ASSISTANCE International Committee of the Red and penetrating wounds. A significant the weeks and months that follow. This certain cancers, such as leukaemia and Cross, who was one of the first foreign number of people would be left deaf, RADIOACTIVE FALLOUT unique consequence of nuclear weapons thyroid cancer. Over time, many more The medical needs of the wounded doctors to arrive in Hiroshima and assess owing to ruptured eardrums. RELEASED BY A NUCLEAR would affect persons located outside the lives would be lost. and sick in the aftermath of a nuclear the effects of the atomic bombing. It EXPLOSION immediate proximity of the explosion, bomb explosion would be enormous. An was immediately clear that the human The accompanying firestorm: as those close to the explosion are likely In Hiroshima and Nagasaki the fatalities overwhelming number of people would suffering and loss of life there were The fireball and heat would raise The immediate effects of radiation include to have died from fatal burn and blast attributed to the bombings had, by 1950, need immediate treatment for severe catastrophic, as was the impact of the temperatures to such levels that many the following: injuries. Radioactive fallout may also be risen to 200,000 and 140,000 respectively.3 and life-threatening wounds, but no such explosion on the medical infrastructure objects and structures not immediately carried considerable distances downwind, Leukaemia incidence increased during treatment or assistance would likely be and medical services. vaporized would burn. The combination ● central nervous system dysfunction (at exposing a much larger population than the late 1940s and reached a peak in the available in the short term.5 of the heat and blast would cause fuel very high doses); that affected by blast and fire. mid-1950s before decreasing to a lower As noted by Junod, and indicated in storage tanks and flammable liquids to but still elevated level. The risk of cancer The explosion of a nuclear weapon exacts the table above, Hiroshima’s medical explode. As a result, large numbers of ● nausea, vomiting, and diarrhoea from Many affected individuals would not of the breast, oesophagus, colon and lung a heavy toll on the medical services. In infrastructure was devastated by the fires would ignite and potentially create damage to the gastrointestinal tract, be aware that they have received a also rose, particularly in people exposed the area affected by the explosion most bombing, with most of its skilled medical an immense firestorm as winds and leading to potentially fatal dehydration potentially lethal radiation dose until to high levels of radiation.4 Even today, medical personnel would be dead or personnel killed or injured. Structurally, intense heat combine the individual fires. and nutrition problems; and days or weeks after the explosion, when radiation-related illness and death are wounded and most medical facilities a Japanese Red Cross hospital, located A firestorm consumes all nearby oxygen the damage to their blood system would seen among the now elderly survivors. would be destroyed or unable to function. 1.5 km from the epicentre, remained and many seeking safety in shelters ● destruction of the body’s capacity to become evident from bleeding from the Any medical supplies that survived the largely intact. However, it could no above or below ground would be likely to produce new blood cells, resulting in gums, or from uncontrolled infections or 3 The Committee for the Compilation of Materials on Damage Caused explosion (e.g. fluids, bandages, antibiotics longer function as a medical facility as by the Atomic Bombs in Hiroshima and Nagasaki, Hiroshima and die from asphyxiation. Those that survive uncontrolled bleeding (because of the wounds that fail to heal.2 Nagasaki: the Physical, Medical, and Social Effects of the Atomic and pain medicines) would quickly be used its equipment was unusable, a third of the lack of oxygen would be at risk of absence or severe reduction of platelets) Bombings, p. 369. up. There would be no electricity for X-ray its staff had been killed and there was no 4 British Medical Association, The Medical Effects of a Nuclear War, pp.