Pathological Effects : Dr. Issei Nishimori
HOME>Pathological Effects : Dr. Issei Nishimori

Dr. Issei Nishimori
Professor Emeritus of Nagasaki University
The following is based on a speech on 29 June 1995 at Nagasaki University .
- Introduction
- At 11:02 a.m., August 9th and after,,,
- Nuclear Bomb Casualties
- Nuclear Bomb Casualties (Continued)
- Epilogue


When the atomic bomb struck Nagasaki fifty years ago, I was a senior in the medical school. I was in the outpatients ward with my professor, giving consultations. Which makes me one of the few survivors from the bombed area. Later as a pathologist I specialized in casualties related to atom bombs. I have studied some 15,000 autopsy cases of bomb victims during the last forty years. Finally as a member of the advisory body to the Health Minister regarding laws to help A-bomb victims, I have seen how the administration side handles this issue as well.

As you can see, my involvement with the atom bomb is many-sided. But today I would like to talk mainly from the pathologist's point of view, beginning briefly with my personal accounts.

As Japan spread the war in China in late-1930s, military doctors became more in need. Correspondingly, medical schools throughout Japan set up additional departments as an emergency measure. At that time, I was in today's equivalent of high school in Kochi Prefecture. In 1938, the government declared Kokumin Sodoin Ho and legalized its absolute power over its citizens by the name of national security. Every Japanese could now be summoned to participate in the war effort.

In 1941 the Pacific War broke out. To speed up graduation in high schools and universities, school system was restructured. Thus I entered university six months earlier, in October 1942. At that time, popular departments were military-related -- engineering and science. On the other hand, most medical schools had vacancies. At Nagasaki Medical College, where I applied along with some thirty other students, the capacity was eighty students per year. There was no entrance examination. I met the Dean, Susumu Tsuno-o, chatted with him for about ten minutes about Torahiko Terada -- a famed scholar who was also from Kochi --, and was accepted on the spot.

At Omura, just off Nagasaki, the Japanese Air Force had a base from where they took off to China. Naturally it became one of the prime targets for the U.S. military. Every time Omura was bombed, we organized a rescue team and headed out.

In Nagasaki there were five U.S. air raids before the nuclear bomb was dropped. When we were attacked for the second time, I was taking my final examination at the surgery department. After the raid, my professor and I did not sleep for two days and two nights. We were treating the wounded that were brought in from the train station and the harbour. Both were packed when the bombing began. Eventually things settled down and I went back to my exam. The professor told me it was no longer necessary.

During the third raid, the Teachers' College in Ohashi-machi was struck down. Then came the fifth, which was the largest. Both Mitsubishi Shipyard and Mitsubishi Steel Manufacturing factories were destroyed, where a major portion of armaments had been produced for the Japanese Army. A number of large bombs fell on our hospital as well, in spite of the big red cross sign on the roof. Three students died, many more wounded. By this time the Japanese military was losing everywhere, but the government was adamant to fight on till the end. Students were no longer exempted from the draft. Those that were not immediately called into service went to work in the military factories. Only the medical students were allowed to finish their studies, but the program was shortened from four years to three, and we had to carry on without any rest. Seven days a week.

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At 11:02 a.m., August 9th and after,,,

On 9 August, 1945 at 11:02 a.m., the atomic bomb was dropped on Nagasaki. That morning I was in a dermatology lab, discussing with my colleagues what we had heard from Dean Tsuno-o on the previous day.(Every month on the morning of 8th -- because the Pacific War broke out on the 8th of December --, students and teachers were to assemble in the school yard and the Dean gave a talk.) On his way back from Tokyo, he had stopped in Hiroshima to study the state of its recent damages. He had said the city was completely destroyed by a special bomb, and we were all making guesses -- that this extraordinary bomb may have used the solar energy, or that it was probably an umbrella-shaped bomb, or that there must have been some application of nuclear technology (which was more or less correct).
Then I saw Prof. Kitamura of the Dermatology Department walking by. So I followed him to the outpatients ward, and stood behind him to study his diagnosis. Suddenly there was a flash, a thunder, and a split second later, I was blown and smashed against the wall. When I opened my eyes, I saw hospital staffs and nurses in a corner. They looked like they were just dumped together.

I thought a bomb had directly hit us. It was hard to breath in the half-collapsed room, so I managed to climb up on what had remained of the roof. All around me there was nothing but destruction. As if the world had come to the end. I struggled down to the hospital entrance, and it was hell. Some were already dead. Others were naked, their clothes peeled off and their whole body burnt. Still others were bleeding. Their entire body. My body was also bleeding, but I could still lend a hand to people trapped in the collapsed building.

Soon fires broke out. Those who could escaped to the mountain in back of the hospital. I met one of my colleagues, looking relatively well, who helped me up the mountain side. About half way to the top I found a flat space. It was just under ANA-KOBO, where Kobo-Daishi -- one of the most saintly Buddhist monks -- is said to have stayed. I lay down to rest. I had lost too much blood and soon fell unconscious. When I realized, it was already early evening. The university and the hospital were both completely enveloped in fire. The sun was blurry behind the smoke. I decided to go home. It took a long time, and by the time I reached my room at the back of IRABAYASHI Primary School, the night had long set in. I learned later that nobody survived from the lab, where I had left my discussion group. (This lab was located in the northern half of the hospital building.)

At the medical school, classes were held normally, for the air-raid warning had been reduced to a regular warning. Everyone died behind his desk in the lecture rooms.(*)

(*)Of the 580 registered medical students, 414 were killed by the bomb. Those who survived only did so because they were not at school on that day. In the Pharmacology College, most of the 201 students were working in the military factories -- 1st years were at Mitsubishi Electric in Awanoura, 2nd years at Japan Nitro Engineering in Minamata, Kumamoto, and 3rd years at Takeda Pharmaceutical in Yoshitomi-cho, Fukuoka -- and escaped the bomb. But 36 students and 2 professors, who happened to be at school, lost their lives. In total, 892 students, teachers, nurses, and staffs were killed at the medical school and the hospital. Of the 737 students in the Teacher's College, 320 were in military, 14 had taken leave, and 293 were working in the military factories. 54 students died. Because they were on campus. At Mitsubishi factories in Ohashi-machi and Mori-machi, where some of our students worked, 2,273 were killed. 580 of them were students, 1,358 were regular employees, and the other 335 were other staff members. The bomb also wounded 5,679, of which 1,058 were students, 4,260 regular employees, and 361 other staff members.

When the war ended, I was still in bandage from head to toe. But I wanted to go home, so that if I were to die it would be in my home village. With my late best friend's ashes, I boarded what had been the freight train. It had no ceiling. It was meant to carry coal. At home there was enough to eat, which was a significant improvement to the food situation in Nagasaki. Had I chosen to remain in that city, I don't think I could have sustained my life.

In the mean time, the medical school restored its regular four-year program, and the classes were resumed among the few that had survived. Temporary lecture rooms were set up in the former Omura Marine Hospital, and later at the former sight of Isahaya Spinning Factory (where Kenko Isahaya Hospital stands today). But I could not attend them. I was so severely injured.

In September 1946 there was a humble graduation ceremony at this temporary campus. 33 of us and 4 professors. Our festive treat was 3 steamed potatoes.

Following the order from the General Headquarters (GHQ) the new medical graduates had to go through an internship before going into practice. That same year, the national examination for medical license was also introduced.

Radiation had decreased my white blood cells to 3,000. Also there were over thirty external wounds. I was getting better, but very slowly.

In 1947 I joined the Pathology Department at Nagasaki University. A learned professor, Shigeru Matsuoka, had just come to head the department, and I wanted to work with him. New professors also came from the abolished universities in Manchuria and Taipei, as well as from other universities in Japan. But we had neither medicine nor lab equipment, and for a while the professors were graded based on how well they grew vegetables.

In those days, the lab training was conducted in the basement of the burned hospital building. We had microscopes donated from former students, but only enough to go around to half of the class. So we had two sessions, one in the morning and the other in the afternoon. (The other day I saw my former students from these years -- at a gathering for the retired professors!)

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Nuclear Bomb Casualties

From early on I became involved in the studies of atomic bomb-related casualties. As my mentor, Prof. Matsuoka, was the forerunner of blood vein-related pathology (KEKKANBYORI) our research had been centered around diseases in brain blood vein (NOU KEKKAN BYORI). Then we became part of the special group set up by the Education and the Health and Welfare Ministries to study atomic bomb-related casualties in Nagasaki and Hiroshima.

On the day the bomb struck, very little medical treatment was possible at our hospital. Although we had eleven emergency teams of doctors, nurses, and students, only two were in any shape to operate at all. These were namely: Team No. 6, based in NAMESHI headed by Prof. Shirabe, and Team No. 11 in MITSUYAMA, headed by Takashi Nagai (Dr. Nagai's deeds were recorded in a journal that became widely known when it was discovered twenty-five years later).

Immediately after the bombing, a team of researchers from Kyushu University, Kumamoto University, and Ube Medical College(now part of Yamaguchi University) came to Nagasaki to conduct pathological studies. Similar study was also conducted in Hiroshima by researchers from Tokyo, Kyoto, Osaka, and other Universities. During the four months following the bomb attack, the two teams conducted autopsy of as many as 145 A-bomb victims in Hiroshima and 94 in Nagasaki.

Their research was compiled into "Pathological Study of Atomic Bomb Casualties (GENSHIBAKUDANSHO NO BYORI)" (Jin MIYAKE and Ryojin KINOSHITA eds.), and was presented at the 12th General Conference of Japan Doctors Association (NIHON IGAKU SOKAI) in 1947. Around this time, however, the GHQ began to object strongly to presentations of A-bomb-related research. With rising tension between the U.S. and the Soviet Union in the Korean Peninsula, the effect of A-bomb on human body was certainly classified information. Consequently the number of reports on this issue dropped to almost none.

Additionally, the U.S. Military took away the organs that had been removed during the autopsy in Hiroshima and Nagasaki. The Japanese researchers had intended on further study, but the organs were shipped back to the United States along with the autopsy data. In 1949, the American Journal of Pathology(AJP) published a report by Liebow, A.A. and others. This "Pathology of Atomic Bomb Casualties" was based on the autopsy data from Hiroshima and Nagasaki. It became the most comprehensive study of the kind.

When Japan Pathological Association held its general meeting in Nagasaki, chaired by Prof. Matsuoka, in 1965, those involved in the A-bomb-related pathological studies held a closed door session on the eve of the general meeting. Some were angry that the United States had taken our colleagues' data produced under extreme difficulty. During this session, I proposed that we request for a partial return of the organs. I had seen them preserved at the American Federal Institution of Pathology(AFIP) in Washington D.C. while I was a visiting researcher at the University of Louisiana (1958 to 1960). After long and complicated negotiations, we finally received our share in 1973, including photographs, copies of written records, and the organs from the autopsy. Research centers were set up in Hiroshima and Nagasaki Universities to keep the material in appropriate condition.

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Nuclear Bomb Casualties (Continued)

The atomic bombs used in Hiroshima and Nagasaki were made with Uranium 235 and Plutonium 239, respectively. They were different in shape and features, but both utilized combustion energy from splitting atoms -- by colliding neutrons against nucleus--, or nuclear fission. Their destructive powers are calculated at roughly 12.5 kt of TNT for the Hiroshima bomb, and 21kt of TNT for the Nagasaki bomb.
When an atomic bomb strikes, it causes:
1. The heat ray of some million degrees centigrade that burns everything near the flashing point.
2. An extremely high atmospheric pressure at the center(several hundred-thousand times the normal pressure), creating blasts that destroy both human bodies and buildings.
3. Release of radioactive rays. Gamma ray and neutrons are the most harmful to human body, but the residual ray also affects organs in countless manners.

The combined effects of heat, blast, and radiation are quite complex, and specific symptoms differ from patient to patient. With respect to radiation, its level is determined by the total volume of gamma ray and neutrons one was exposed to. A closer look would reveal, however, that patients from Hiroshima were exposed more to neutrons than to gamma ray, while the proportion was reverse among the victims from Nagasaki.

Broadly speaking, atom bomb-related casualties can be divided into those that occur during the first four months following the strike ('acute symptoms (KYUSEI BYOHEN)'), and those that appear later on ('late defects (GENBAKU KO SHOGAI)'). The latter naturally includes symptoms that are still developing, as well as hereditary influences on future generations. Our university hospital has a research center dedicated to the studies of this latter type of casualties.
Based on the previous report headed by Miyake and Kinoshita, Liebow's report in the American Journal of Pathology, and our reexamination of the returned data from the U.S., we divide A-bomb casualties as follows:

a. Acute Symptoms
1) Immediate Symptoms(0 - 14 days after the bomb attack):
  In both Hiroshima and Nagasaki, the death toll during these two weeks exceeded all other periods. More than 90% were instantaneous, either from collapsed buildings, enormous pressure, or severe heat. Clinical record also shows that some patients began to suffer from bleeding and decrease in white blood cells, both indications that their hematogenous organs had been affected.
2) Acute Symptoms(15 - 35 days after the attack):
  Major clinical symptoms were all radiation-related -- high temperature, dullness, bleeding of gum, and bloody excrement. As these symptoms worsened, many victims, who otherwise had no fatal wound or burn, lost their lives. Also, a number of patients began to lose their hair -- another effect of radiation. Pathologically, hematogenous dysfunction was the most commonly observed symptom. Production of white blood cells, red blood cells, as well as blood platelets had stopped almost altogether, and the patients' bone marrow came to resemble those with aplastic anemia. This clearly shows that hematogenous organs were the most vulnerable to radiation.
3) 36 - 60 days after the attack:
  Infection, which the damaged hematogenous organs could not prevent, caused many deaths. Some also suffered jaundice. Among the relatively less serious patients, blood producing function began to restore, and their white blood cells and blood platelets started to increase.
4) 61 - 120 days after the attack:
  By this time, most symptoms stopped advancing. Lost hair also began to come back. On the other hand, many died from RUISO or damages in kidney and/or liver.
5) Keloid:
  Heat burns from the bomb often developed into bulbil (NIKUGA), many of which became keloid. This bomb-related type was accompanied by distinctive features. Compared to keloids that sometimes develop from a burn or an operation, a heat burn from the bomb was much more likely to turn into a keloid. The change usually occurred after the first four months, but we classify keloid here because its causes are obviously acute symptoms. After about one and a half years, the keloid would stop growing and would slowly harden, eventually forming permanent marks on the body.

b. Late Defects
Atom bomb- (especially radiation-) related diseases also developed after the first four months, of which cancer and leukemia are the most problematic. Because there is no distinctive feature to differentiate them from the cancer and leukemia that are not related to the bomb, it is very difficult to prove that the atom bomb was their cause.
1) A-bomb Cataract:
  Usually cataract is a common disease among the old, but A-bomb victims from near the flashing point often suffer this disease from relatively young age. This type of cataract is easily detected by opaque spots in lens that do not follow the pattern of regular cataract patients'. However, when an A-bomb victim develops cataract after reaching a certain age, it is difficult to determine whether or not this is related to the bomb.
2) Leukemia:
  About five years after the attack, leukemia became alarmingly noticeable among the A-bomb victims, as had been feared, for it was known that doctors and nurses who work with X ray are more prone to leukemia than an average person. The data shows strong correlation between the level of radiation one was exposed to and one's proneness to leukemia (see chart 1 below).
As for myeloma, Prof. MICHITO ISHIMARU of Nagasaki University pointed out in his research that bomb victims that were of old age and had been exposed to a significant amount of radiation were likely to develop this disease. Our analysis of autopsy data also supports his research.
3) Cancer
  a. Thyroid Gland Cancer: Thyroid Gland is one of the sensitive organs to radiation. After about eight years and onwards, many female victims from the bombed center -- and those that were young -- became afflicted with this cancer.
b. Breast Cancer: Another sensitive organ to radiation. Numerous studies all point out that the younger the victim was, the more prone she became to this cancer.
c. Studies on cancers in liver and digestive organs are still under way, since all cancers do not come out at the same time.
4) Radiation Effects on Fetus:
  Most of the victims that had been less than 18 weeks pregnant at the time of bomb strike had miscarriages or stillborns. The few babies that did survive were liable to suffer from overall growth defects or mental disorder. Sometimes the baby's head would be smaller than an average child's (This is called GENBAKUSHOUTOU SHO). In Nagasaki one such patient lived until the age of 16, in spite of serious growth defects in the cerebrum.
5) Hereditary Influence:
  It is reported that in animal tests, if the parents are contaminated by radiation the abnormality in children is more common than average. However, there is no report from Hiroshima nor Nagasaki that there are radiation-related defects in children of bomb victims. Some suggest that human hereditary influences take into account other environmental factors and are more complex, so that the effect of the bomb might be concealed. Others say they need to trace five to six generations in order to reach a meaningful conclusion. Research shall continue in this field, although this is no easy task. For the privacy of victims must be protected, and the victims are spread out.
Heterochromosomes are reportedly more prevalent among the bomb victims than the average, but this does not necessarily result in a disease. What is more, it must be noted that the children of bomb victims do not carry heterochromosomes.

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For forty years, I have done what I could to report on the effects of atom bomb as a medically-trained professional. To me it seemed to be the most effective means against the spread of nuclear arms. Before I close today, may I remind you that what I just talked about is the aftermath of an atomic bomb from 50 years ago -- when the bomb was still infantile. Today's nuclear arms are much, much more powerful. Yet the arms race continues, ignoring people's cry against it. I hope my brief report has shown you how even a baby bomb could, and continues, to this day, to damage so many lives. We really must work towards a nuclear-free future. Thank you.

Dr. Issei Nishimori and
his bloodstained lab coat.

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All Pages of this series were translated by Masako & Hiroki Ichinose.






  The Medical Effects of Atomic Bombing  
  Atomic Bomb Rescue and Relief Report:Dr.Takashi Nagai  
  Pathological Effects : Dr. Issei Nishimori  
  My Experience and Damages : Dr. Raisuke Shirabe  
  Dr. Raisuke Shirabe's Survey Sheets  
  Final Report of Manhattan Investigation  
  Materials and Data  
  A-bomb experiences of medical staffs  
  Exhibition Room  
  Atomic Bombing Q&A for Kids  
  Atomic Bomb Survivor Database  
  ABDI 50th Anniversary exhibition:Investigation just after the bombing  
  Takashi Nagai 60 years Memorial Celemony after his death  
  30th Anniversary Meeting for Establishment of Database  
  Doctors' Experience of Atomic Bombing -60th Memorial Ceremony -  
  Division of Scientific Data Registry
Biostatistics Section
Tissue and Histopathology Section
Research Reports