Effort to clarify number of A-bomb victims who died by the end of 1945

by Toshiko Bajo, Staff Writer

The City of Hiroshima has included an allocation of 9.5 million in the draft of its initial general account budget for fiscal year 2010 for its Statistical Survey of Atomic Bomb Victims. The survey is intended to give a complete picture of the bombing by compiling a list of names in order to determine how many people in Hiroshima were exposed to the bombing and how many died as a result. This is about four times the amount appropriated in the fiscal 2009 budget and far more than has been budgeted in recent years. But no new lists or other materials relating to those who had died by the end of 1945 have been found. This represents the biggest gap in knowledge surrounding the bombing, and efforts to clarify this have come to a standstill. The Chugoku Shimbun looked at the current state of the survey and the issues faced, including the methods the city will introduce next fiscal year as well as to what extent those methods will allow the gap in knowledge to be filled.

Past developments and current status

The city's statistical survey is intended to reveal the extent of the human suffering brought about by the atomic bombing of Hiroshima, focusing on the creation of a list of the names of all those who had died by the end of 1945. The first stage of the Survey of Victims of the Atomic Bombing, as it was then called, began in fiscal year 1979. The name of the survey was changed to the current name with the 2nd stage, which began in 1982.

Through the 6th stage (fiscal 1995-1998), the survey was conducted in three- to four-year stages. But the 7th stage, which began in fiscal 1999, has not yet been concluded. Why?

The main reason is that little progress has been made in determining the number of people who had died by the end of 1945. Although a total of 1,032 were identified in the 6th stage, only 166 more were identified during the 10 years of the current 7th stage through the end of fiscal 2008, bringing the total number of those who died to 89,031. This is far below the estimate of 140,000 (+/- 10,000) that is generally cited.

While the initial budget amount the city appropriated for the survey reached about 30 million in fiscal 1986, the maximum allocation in the 7th stage was 15.7 million in fiscal 1999. Since then the figure has continued to decline, hovering around 2 million since fiscal 2005.


Masahiro Urushihara, director of the city's Atomic Bomb Survivors Relief Department, cites the inability to locate new materials as the reason for the difficulty in identifying others who died in the bombing.

In the 1st stage, various materials were checked against each other. This included data from the Atomic Bomb Damage Survey conducted from fiscal 1969 to 1976 by Hiroshima University's Research Institute for Nuclear Medicine and Biology (now the Research Institute for Radiation Biology and Medicine) and other entities as well as the Hypocenter Reconstruction Study conducted from fiscal 1968 to 1976. Through the 5th stage, materials preserved by neighboring local governments and hospitals were also incorporated into the survey. Names included on more than one list were deleted, and the work of compiling the list steadily moved forward. With the implementation of the Atomic Bomb Survivors' Relief Law in 1995, applications by victims' families for the Special Funeral Benefit for Atomic Bomb Survivors led to the identification of a certain number of victims during the 6th stage.

The materials that have been compiled thus far are diverse and include government materials from municipalities and police departments in the surrounding area as well as lists of mobilized students and company employees who fell victim to the bomb. In recent years there have been no reports of the discovery of a significant amount of other atomic bombing-related materials. "The fact that no more materials have been found should be regarded as an indication of the success of the effort that has been put into the investigation thus far," Mr. Urushihara said.

There are other obstacles to gathering materials. For example, in many cases applications for survivors' certificates include information such as the addresses of relatives at the time of the bombing and whether or not they were living then, which could provide promising leads. But these applications are held by the prefectures to which they were submitted, and it is difficult for other prefectures to provide detailed information to the City of Hiroshima because of the need to protect privacy.

The possibility that many "nameless" victims have not been included in the statistical survey has also been pointed out. One reason for this is the fact that entire families were killed. It is also believed that the identities of many Koreans may have been recorded under Japanese names or they returned to their homeland shortly after the bombing. Thus there is often no clue to their identities. At this point it has become even more difficult to determine the identities of many victims, including military personnel.


Although the city intends to continue its effort to pin down the number of people who died by the end of 1945, in view of these circumstances it has taken the position that it has no choice but to rely on the discovery of new materials or requests for inclusion by relatives of victims.

In that case, what will be done in the new fiscal year? The city has included an appropriation in its initial budget to contract out research to Megu Otaki, a professor of statistics at the Research Institute for Radiation Biology and Medicine. Mr. Otaki will employ several assistants using a subsidy from the central government's Emergency Job Creation Program to help with the compilation and statistical processing of the data that has been accumulated thus far. According to the city, in addition to checking for duplicate names, the aim of the project is to cross-check survey data against data held by the institute in order to improve accuracy.

"Coming up with more accurate figures is not the only goal of the project. We want to determine where each victim was at the time of the bombing," Mr. Urushihara said. "In many cases, the families of the victims are unknown. By organizing the data, we may be able to identify surviving family members in some cases. We will be getting a government subsidy and have the cooperation of Professor Otaki, so we would like to take this opportunity to get a clearer picture of the extent of the human suffering."

Statistical Survey of Atomic Bomb Victims

1st Stage: Fiscal 1979-1981...402,491 (total number of victims)...77,902 (those who died by the end of 1945)
2nd Stage: Fiscal 1982-1984...490,222 (total number of victims)...85,278 (those who died by the end of 1945)
3rd Stage: Fiscal 1985-1987...462,924 (total number of victims)...77,113 (those who died by the end of 1945)
4th Stage: Fiscal 1988-1990...516,611 (total number of victims)...90,104 (those who died by the end of 1945)
5th Stage: Fiscal 1991-1994...522,664 (total number of victims)...87,833 (those who died by the end of 1945)
6th Stage: Fiscal 1995-1998...541,817 (total number of victims)...88,865 (those who died by the end of 1945)
7th Stage: Fiscal 1999-Present...89,031* (those who died by the end of 1945)
*Identified as of the end of fiscal year 2008 (unverified).

Interview with Satoru Ubuki, professor at Hiroshima Jogakuin University: Continuing a careful investigation is vital

Satoru Ubuki, a professor at Hiroshima Jogakuin University, participated in the gathering of materials related to the Statistical Survey of Atomic Bomb Victims through 2001 while working at Hiroshima University's Research Institute for Radiation Biology and Medicine. The Chugoku Shimbun asked him for his analysis of the current state of the survey and the issues faced. Below are Professor Ubuki's thoughts:

It stands to reason that as time passes it becomes more difficult to compile data. And as the survey proceeds, it gets harder to find materials.

But the statistical survey will play a large part in ensuring that the number of victims of the bombing does not end up as some imprecise estimate. Is it acceptable to say that there were "about this many" victims? Hiroshima must not do that.

It is estimated that 140,000 (+/- 10,000) victims died by the end of 1945, but there is debate as to whether or not this figure is really correct. I have doubts about making obtaining this figure the aim of the survey. But I believe continuing the statistical survey is meaningful. It is essential for Japan to take the position that it intends to elucidate the extent of the human suffering wrought by the atomic bombing.

The survey has compiled a list of the names of the victims primarily based on materials belonging to the government. But it should be possible to identify the names of those who died as well as survivors by using private papers, newspaper articles and other similar materials. [With regard to those who died from 1946 on and those who are living,] it is possible that the names of those who were first issued survivors' certificates in other prefectures have not been included. [With changes in the central government's definition], the scope of the area exposed to radiation has also changed. A detailed check must be made to ensure that there are no omissions and to make certain that these things are reflected in the survey.

Even now we do not know where many people died. Clarifying that would be very meaningful for their families and friends. This survey can only be conducted by the government. The city must do what it can to determine exactly how many people were exposed to radiation from the atomic bombing and what effects they suffered.


140,000 (+/- 10,000)
The estimate of the number of those who had died in Hiroshima by the end of 1945 was originally made in 1976 by the Committee for the Compilation of Materials on Damages Caused by the Atomic Bombs in Hiroshima and Nagasaki, which was chaired by Seiji Imabori, then a professor at Hiroshima University. The committee’s estimate for Nagasaki was 70,000 (+/- 10,000). The report was submitted to the secretary-general of the United Nations by the cities of Hiroshima and Nagasaki. Minoru Yuzaki, an associate professor at Hiroshima University’s Research Institute for Radiation Biology and Medicine, served as a member of the committee. He said his figure was based on the population of the city and its environs as well as estimates of those in the city who were from outside the prefecture, military personnel and Korean forced laborers.

(Originally published Feb. 23, 2010)

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