The major effect on the victims of the Bombing of Hiroshima and Nagasaki was mostly the aftermath of the bombs. Harmful radiation caused by both explosions were enough to be fatal to humans. Gamma Rays and radiation at high amounts can damage DNA, and radiation poisoning killed many people in the aftermath of both of the nuclear explosions. The blast was bright enough for many people to lose their vision, and the heat was so intense that it burned people's skin, sometimes even melting off the bone.
Later on, many victims of the bombings of Hiroshima and Nagasaki are prone to developing cancer in the near future. Victims can develop cancers that have never been treated before, to developing multiple cancers at the same time. This is all because of Gamma Rays emitted by the nuclear explosions that damaged the DNA in cells, causing cells to mutate and split uncontrollably
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