Hiroshima Bombing Radiation Was Far More Dangerous Than We Thought

hiroshima bombing
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The Hiroshima bombing was an effective yet absolutely devastating end to Japanese involvement in World War II, and recent research shows just how much radiation victims of this “cruel bomb” were exposed to.

The research regarding the radiation effects of the Hiroshima bombing is a long time coming, with the project first started back in the 1970s. According to Sergio Mascarenhas from the University of Sao Paulo, the X-ray and gamma radiation of the Hiroshima bombing caused bones to become “weakly magnetic” – a phenomenon named paramagnetism.

Back in the 1970s, Mascarenhas obtained a jaw bone from a Hiroshima bombing victim and attempted to figure out how much radiation the bones had absorbed. This most recent study also took samples from the same jaw, but our research methods have come a long way since the 70s – with tools like electronic spin resonance spectroscopy giving us clearer insight into the effects of radiation on these unfortunate victims. In order to get a sense of the magnitude of the damage, the samples were irradiated back to the original level of radiation the bone would have experienced with the dropping of the atomic bomb.

Oswaldo Baffa, the study’s co-author and a professor at the University of Sao Paulo, stated that “we then constructed a curve and extrapolated from that the initial dose, when the signal was presumably zero. This calibration method enabled us to measure different samples, as each bone and each part of the same bone has a different sensitivity to radiation, depending on its composition.”

The effects of the Hiroshima bombing were devastating, but we didn’t have any idea just how devastating until this recent study, which found that the human jaw bone had experienced 9.46 grays worth of radiation. Considering it only takes 5 grays to kill a human, it’s clear that the damage of the Hiroshima bombing extended far beyond the initial explosion – killing many people through radiation poisoning in the days and weeks that followed.

“We used a technique known as electron spin resonance spectroscopy to perform retrospective dosimetry. Currently, there’s renewed interest in this kind of methodology due to the risk of terrorist attacks in countries like the United States…Imagine someone in New York planting an ordinary bomb with a small amount of radioactive material stuck to the explosive. Techniques like this can help identify who has been exposed to radioactive fallout and needs treatment,” Baffa said.

With tools like electron spin resonance spectroscopy, law enforcement officials and medical professionals alike may be better equipped to respond to terrorist attacks and save lives – perhaps reducing the impact of a radioactive attack by taking quick action to address those who are affected before it’s too late. While the likelihood of people experiencing the same sort of devastating attack like we saw with the Hiroshima bombing is pretty low, the application of this technology to the bombing victim’s bones is reassuring in that it gives us tools to address similar situations in the future. While many people were incinerated in the initial blast of the Hiroshima bombing, there were many more that passed away shortly thereafter from the sickening effects of radiation. The fact that the radiation levels were nearly twice what is required to kill a person really drives home the incredible damage that an atomic bomb is capable of.

The results of this study are titled “Electron spin resonance (ESR) dose measurement in the bone of Hiroshima A-bomb victim” and were first published in the journal PLOS One.