A Nagasaki Survivor And Physician Recounts His Life’s Work

IRA FLATOW: Hey there. It’s Ira Flatow, and you’re listening to Science Friday.

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80 years ago, the US bombed Hiroshima and Nagasaki. So today on the show, an atomic bomb survivor and physician recounts his life’s work and understanding how radiation affects the body.

– I have a fear I should be a leukemia patient. So I finally decided to go to medical school and to learn why leukemia was induced by radiation.

IRA FLATOW: An estimated 210,000 people died instantly or within five months of the bombings of Hiroshima and Nagasaki. Another 210,000 survived and became known as “hibakusha” in Japanese. For decades, hibakusha have been receiving medical care at specialized hospitals designed to care for atom bomb survivors. And to this day, those hospitals are busy and filled with survivors who have suffered the medical consequences of the bombings.

Dr. Masao Tomonaga was a doctor at one of these hospitals. He was just two years old in Nagasaki when the US bombed the city. Years later, he became a physician and ultimately ran a Red Cross hospital in Nagasaki that cared for hibakusha, just like himself. Now he directs a nursing home for hibakusha and still sees patients regularly. Dr. Tomonaga my guest on Science Friday today. Welcome to the show.

MASAO TOMONAGA: Nice to meet you.

IRA FLATOW: Thank you. You were only two years old when the US bombed Nagasaki. What was your first memory of the aftermath?

MASAO TOMONAGA: I have no memory of atomic bombing in Nagasaki, especially what happened in our house. Later, when I became age four or five, my mother explained what happened. My mother was preparing a lunch in the first floor, and I was sleeping on the second floor. But suddenly, the blast came, and our Japanese wooden house half broken, not completely, half broken. So my mother came up to broken second floor and found me in a narrow space under the roof, and she took me out successfully.

If she was not successful to take out me from the space, maybe I was burned by a firestorm firestorm after one hour or two hours. So I was a lucky boy. I was a lucky boy. Yeah. There were many unlucky boys and girls. Yeah.

IRA FLATOW: Your father was a physician. He was a doctor.

MASAO TOMONAGA: Yeah.

IRA FLATOW: Was your father working as a doctor during the bombings?

MASAO TOMONAGA: No, my father actually stationed in Taiwan. He was serving Japanese army air force as a medic. My father first received information about Nagasaki disaster by bombing. He first thought his wife and newborn son already dead. But one month later, a letter from my mother reached him. So he was so glad to read.

IRA FLATOW: So he came back to Nagasaki. Did he take care of the survivors when he returned?

MASAO TOMONAGA: Yeah, he became one of the main doctors who take care of atomic bomb survivors, especially as a hematologist. It’s a blood disease specialist. And later, my father found, among children, acute leukemia case started to increase.

IRA FLATOW: So the leukemia was due to the radiation?

MASAO TOMONAGA: Yeah, this was actually due to radiation because the distance from the ground zero, this distance, the shorter the distance, the increased incidence of acute leukemia among citizens was increased. We call it dose-dependent. Dependency was clearly shown.

IRA FLATOW: So your father was one of the first people to realize that the leukemia he was seeing was becoming more common in the survivors. Correct?

MASAO TOMONAGA: Correct. Correct. that was happening also in Hiroshima city, simultaneously, as if there were two experiments, massive radiation on citizens.

IRA FLATOW: So let’s move a little bit ahead. Why did you decide to become a doctor?

MASAO TOMONAGA: My family was, actually, from my grand grandfather, all doctors. So I was grown up surrounding doctors. So it was my natural will to become a doctor. And more than that, when I became a high school boy, I must prepare for an examination in medical school. My knowledge about atomic bomb-induced leukemia was increased. So I have a fear I should be also becoming a leukemia patient. So I finally decided to go to medical school to learn why leukemia was induced by radiation, atomic bomb radiation. Yeah.

IRA FLATOW: After you graduated medical school, why did you want to study and take care of other survivors? Why was that important to you?

MASAO TOMONAGA: Yeah, when I became a doctor, and I decided to enter hematology to study and treat leukemia patients as a hibakusha care doctor. Yeah, so this continued over entire my life, because the diseases which developed from atomic bomb survivors continued even now, even now.

IRA FLATOW: Are there still any cases, do you think, of illnesses from the radiation, whether it’s leukemia or others, still being discovered left from the bomb?

MASAO TOMONAGA: Yeah. Actually, we first observed leukemia increase in the first 20 years, but leukemia began to decline gradually. We thought this was the end of radiation effect on human beings, but it was not true. Around this 20 years phase, cancer, solid cancer, such as lung cancer, colon cancer, and so on, began to increase among many survivors. So it continues long, very long until present time.

And other than leukemia, we’ve discovered that in 1980s, almost 40 years after atomic bombing, another disease, which is similar to leukemia, but quite different disease of the elderly people. Elderly leukemia began to increase. That’s name is myelodysplastic syndrome. Abbreviation is MDS. This is the first discovery in Hiroshima and Nagasaki. This is continuing now. So after 80 years, radiation effect is continuing.

IRA FLATOW: Is that surprising? Was that surprising to you?

MASAO TOMONAGA: Yes, surprising, surprising. So we decided to begin research on why such a long time induction of malignant diseases by radiation actually happens. There must be some mechanism for this. We finally discovered that those radiation causes genetic abnormality in each cells of organs. And some of the such cells are called stem cells. Very primitive cells, which everyday produce red cells, white cells, and so on. But still, these cells are not leukemia cells. This condition continues for more than 60 years, 70 years. Some of them began to develop actual MDS.

And MDS is also a lethal disease, because after four or five years of mild clinical course, many MDS patients develop acute leukemia, and finally die. The treatment is very inactive. So we must say leukemia and other cancers related to radiation are lifelong effect of atomic bombing.

IRA FLATOW: Wow. Those are the long term effects.

MASAO TOMONAGA: Very long term. Very long term.

IRA FLATOW: Yeah, they certainly seem surprising. Who would have thought that 80 years later?

MASAO TOMONAGA: No one. No one. Actually, we didn’t at all.

IRA FLATOW: Yeah. But there were those short term, immediate effects from the bomb itself. Right? We had miscarriages, birth defects, not to mention the severe burns.

MASAO TOMONAGA: Yeah, severe burns was the most popular injury given by atomic bomb heat rays. Those who died of severe burn, the number was the greatest among the deaths of hibakushas.

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IRA FLATOW: Coming up after the break. How the atomic bomb lives on.

MASAO TOMONAGA: She said, I was confident that atomic bomb is surviving in my body, deep, deep, deep body.

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IRA FLATOW: What about the psychological effects?

MASAO TOMONAGA: Yeah. We doctors responsible for hibakusha care began to see many hibakushas who are exposed to high dose radiation begin to complain every year during the atomic bomb season. That starts about June, July, August. They often complain of sleeplessness, anxiety, and the flashback of atomic bomb experience. And their psychological condition deteriorates remarkably. So we performed 8,000 large scale psychological examinations by using WTO questionnaires, which is powerful scoring methodology.

12 is a large, highest scores. So we found within 1.5 kilometers from the ground zero, almost all survivors showed very high scores over 10 to 12. So this was our surprise. That was done in the 1995. 50 year anniversary of atomic bombing, we performed this large scale study.

IRA FLATOW: What about now?

MASAO TOMONAGA: Yeah, I begin to feel that their memory is fading, fading out. In their 50s, 60s, their memory was a very clear, and they always complained of their experience. But recently when they got over 80 years, their memory seemed to be fading, fading, fading. So that is a maybe good point for them to– they have been relieved from the anxiety and depressive states. They are now very spending calm days.

IRA FLATOW: Yeah, and that you followed them, because I understand you run a nursing home for other survivors. Tell me about that. How many people there?

MASAO TOMONAGA: 450, 450, in total. And every day, I examine 20 to 30 patients who suffer from transient fever, diarrhea, and sometimes coronavirus infection, influenza, and so on. But among such daily diseases, we sometimes find MDS and cancer in cases of short-distance survivors.

IRA FLATOW: I read that some patients describe it like the atom bomb is still in their bodies.

MASAO TOMONAGA: Yeah, that was an astonishing moment for me when I conveyed my diagnosis, acute leukemia, to patients. She was 76 years old at that time, and she said, I was confident that the atomic bomb is surviving in my body deep, deep, deep body.

IRA FLATOW: Tell me more. What did she mean by that?

MASAO TOMONAGA: She meant not radiation itself. Most hibakushas have no such residual radiation, except plutonium. About 20 years ago, one of our researchers at Nagasaki University found plutonium particles deposited in several organs of autopsied cases of atomic bomb survivors, most often, lung and bones. Those calculated from this deposited plutonium particles was so small, very tiny amount. So it is impossible to suspect their after bombing reduction of cancer was maybe negligible.

IRA FLATOW: Negligible. Do you have a message for those of us on this 80th anniversary of the bombing?

MASAO TOMONAGA: Yes. 80 years is enough period if we can understand the atomic bomb is an inhumane weapon. When a large scale nuclear war happens, the human being could be a cessation. So why our society cannot abandon nuclear weapons? That is my largest problem. I’m working for the realization of a nuclear weapon-free world. And I want to talk to leaders of nuclear weapon states. And I urge their decision to make the nuclear weapon be abandoned.

Yesterday, I met some youth at the United Nations, and I talked, and they clearly understood. But how these new generations will protest to their government, especially in nuclear weapon states government, that is very unclear. Yeah, that is the biggest problem.

IRA FLATOW: Dr. Tomonaga, I want to thank you for joining us today.

MASAO TOMONAGA: You are very much welcome. Yeah.

IRA FLATOW: Dr. Masao Tomonaga is a survivor of the atomic bombing of Nagasaki and Director Emeritus of the Japanese Red Cross Nagasaki Atomic Bomb Hospital. Special thanks to Laura Pellicer for her help with this interview.

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This episode was produced by Rasha Aridi. I’m Ira Flatow. Thanks for listening.

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