Radiation Linked to Just 1 Percent of Deaths Among Hiroshima and Nagasaki Survivors, Study Finds

High doses of radiation after atomic bombs posed lower risk than previously thought.
Radiation Linked to Just 1 Percent of Deaths Among Hiroshima and Nagasaki Survivors, Study Finds
The aftermath of the atomic bomb in Hiroshima, Japan, in 1945. AFP via Getty Images
|Updated:
0:00

A study has found that, 80 years after the atomic bombings of Hiroshima, Japan, and Nagasaki, Japan, radiation-related deaths among survivors accounted for only 1 percent of total deaths.

Philip Thomas, professor of risk management at the University of Bristol, said that despite the slightly elevated risk the survivors faced as a result of their exposure to radiation in 1945, their lives will, on average, have been “decades longer than those of their forebears.”

On Aug. 6, 1945, and Aug. 9, 1945, the United States detonated atomic bombs over Hiroshima and Nagasaki during World War II.

The study, published in the latest Journal of Biological Physics and Chemistry, states that the Hiroshima bomb fissioned enriched uranium almost 2,000 feet above the ground to produce an effect similar to that of 16 kilotons of TNT exploding.

A plutonium bomb was detonated about 1,600 feet above Nagasaki three days later, unleashing the same power as 21 kilotons of high explosives.

Large areas of the two cities were devastated, and about 200,000 people were killed immediately or shortly afterward.

Most of the deaths were from blast and burn injuries, but about 20,000 people died from acute radiation poisoning within days or weeks.

The study states that those who survived the bombings had received an “instantaneous dose of ionizing radiation of a size that depended principally on their distance from the hypocentre but also on how well they were shielded by buildings and walls.”

It states that the statistical evidence makes it clear that the population of survivors, including those who had received extremely high doses of radiation and suffered acute radiation syndrome as a consequence, “shared in the dramatic increase in longevity that accompanied Japan’s post-war economic boom.”

This means that a little less than 1 percent of all survivors can be expected to die from radiation-induced cancers.

“Even survivors receiving an average dose of 2,250 [milligray], far above the threshold for acute radiation sickness, can expect to live to a median age of 78 years 169 days, nine months more than the life expectancy at birth for an infant born in the UK in 2000, and a year and ten months longer than an American baby born in that year could expect to live,” it reads.

The study comes after thousands of people bowed their heads in prayer last week in Nagasaki to mark the 80th anniversary of the city’s atomic bombing.

Nagasaki Mayor Shiro Suzuki on Aug. 9 warned that current global conflicts could push the world again into nuclear war and that leaders need to show a path toward abolishing nuclear weapons.

“This is a crisis of human survival that is closing in on each and every one of us,” he said.

On Aug. 1, U.S. President Donald Trump ordered the movement of two nuclear submarines in response to what he called “highly provocative statements” by former Russian President Dmitry Medvedev.
Russia will no longer abide by self-imposed restrictions on the deployment of intermediate-range missiles, the Russian Foreign Ministry announced on Aug. 4.
Trump warned on Aug. 13 that there would be “very severe consequences” if Russian President Vladimir Putin refused to end the war in Ukraine after their summit in Alaska on Aug. 15.

When asked about the nature of those consequences, Trump declined to comment.

“I don’t have to say,” he said. “There will be very severe consequences.”

In 2024, the Nobel Peace Prize was awarded to Nihon Hidankyo, a Japanese organization of survivors of Hiroshima and Nagasaki that is known for its activism against nuclear weapons.

Jorgen Watne Frydnes, chairman of the Norwegian Nobel Committee, said the award was made as the “taboo“ against the use of nuclear weapons is ”under pressure.”

Reuters, The Associated Press, Jack Phillips, and Emel Akan contributed to this report.
Google LogoMark Us Preferred on Google
Owen Evans
Owen Evans
Author
Owen Evans is a UK-based journalist covering a wide range of national stories, with a particular interest in civil liberties and free speech.