Episode Description

Floy Agnes Lee, known as Aggie, was a hematology technician at Los Alamos. Recruited to the Manhattan Project straight out of college, she collected blood samples from many Manhattan Project scientists, including the renowned physicist Enrico Fermi. Years after the war, she returned to Los Alamos National Laboratory to study the effects of radiation on the human body.

Further reading: 

  • Los Alamos Historical Document Retrieval and Assessment (LAHDRA) Project (Centers for Disease Control and Prevention, 2018) The CDC conducted this project to evaluate releases of materials from Los Alamos National Laboratory that had the potential to cause off-site health hazards. Alongside an independent contractor, the organization systematically reviewed all available documents related to LANL operations and identified records that contribute information about releases of chemicals and radionuclides from the site between 1943 and 2010.
  • The Making of the Atomic Bomb by Richard Rhodes (Simon & Schuster, 1986)
    This book covers people and events from early 20th century discoveries leading to the creation of nuclear chain reactions, through the Manhattan Project and the 1945 bombings of Hiroshima and Nagasaki. This Pulitzer Prize winning book is considered a general authority on early nuclear weapons history.
  • “The Demon Core and the Strange Death of Louis Slotin” by Alex Wellerstein (The New Yorker, 2016)
    This article recounts the tragic death of Louis Slotin at Los Alamos on May 21, 1946. Slotin was demonstrating a risky procedure called "tickling the dragon's tail," involving a nuclear weapon core. During the demonstration, a mishap occurred, and the core went critical, emitting a burst of radioactivity that later killed him.
  • "The Slotin Accident: Inside the Archives" (Los Alamos History)
    This blog post from the Los Alamos History Museum provides scans and a transcript of Manhattan Project physicist Phil Morrison’s official letter reporting on the Slotin accident. The post also contains Burt Sauer’s written narrative of the incident, which brings the event into vivid clarity.

Episode Transcript

Blood, Sweat, and Fears: The Story of Floy Agnes Lee, the Young Woman who Collected blood from Manhattan Project scientists

Floy Agnes Lee: It was in 1945, and the bomb was being developed at that time.

And my assignment was to take, collect the blood from the research men who, scientists who were working on the atomic bomb.

Katie Hafner: This is Lost Women of the Manhattan Project. And that’s the voice of Floy Agnes Lee, who started working at Los Alamos National Laboratory in 1945, a year that defined a before and after. A world before nuclear weapons and a world after.

This special series about women who worked on The Manhattan Project is different from what we usually do. We usually strive to educate while also entertaining you, and we always put our subjects’ stories against the backdrop of how women were regarded and treated at the time in which they lived. But in this special series, the only backdrop you need is the backdrop of urgency. The urgency of war and how female scientists joined the fight.

In this, the second in our series, we shine a light on Floy Agnes Lee, known as Aggie, an indigenous young woman who came from the Santa Clara Pueblo Nation and joined the Manhattan Project straight out of college. Her job was taking and analyzing scientists’ blood. This may sound simple, but Los Alamos was a secretive and dangerous place. Many of those who worked there were not told that what they were in fact helping to build was an atomic bomb. Aggie Lee was one, but she witnessed firsthand the horrific effects of radiation exposure on the human body. It changed her life. She went on to spend most of scientific career studying the effects of radiation. 

Producer Monica Lopez brings us the story.

Monica Lopez: Floy Agnes Lee was born July 23, 1922  the child of a German American mother from Indiana and a father from the Santa Clara Pueblo nation just northeast of  Los Alamos.  Her mother and father met at the Indian Boarding School where they both worked.

Floy Agnes Lee: She came as a teacher to teach in the boarding school in Santa Fe and met my Indian father who was teaching tailoring, which he had learned there.

Monica Lopez: They married in Colorado and sent wedding invitations to relatives in Indiana after the ceremony.

Floy Agnes Lee: Because they knew that my, white relatives would object to her marrying an Indian.

Monica Lopez: One of five siblings, Aggie grew up at the Indian boarding school in Albuquerque and attended classes at St. Mary’s Catholic School.

Floy Agnes Lee: The nuns would come from the east and to teach and. They would talk about the savages at the Indian school because that's all they knew that the Indians were called savages. And that really got to me, you know.

Monica Lopez: But Aggie was proud of her indigenous heritage.  She went on to Albuquerque High School, and then to the University of New Mexico and studied biology. Aggie’s father encouraged her to join the military to help pay for college. She tried out for the Women’s Airforce Service Pilots, or WASP’s, and was accepted into the flight training program. 

Floy Agnes Lee: I took flying lessons, soloed and was ready to go into the Women's Air Force, but I had one more maneuver to make before I could go, and that was to do cross country.

Monica Lopez: Aggie wanted to continue flight training, but before she was able to complete it, something else came along unexpectedly.

Floy Agnes Lee: When I graduated from university, the professor, who was head of the biology department, asked me to stay another month and then, he asked me would I like to go to Los Alamos and work there. And I did not have a job lined up, so I said yes. So that's how I got to Los Alamos.

Monica Lopez: Aggie joined the Manhattan Project in the hematology lab in 1945 . She became part of what the US Department of Energy described as “one of the country’s single largest wartime enterprises.” Danish Physicist Niels Bohr had once said that for the U.S. to build a nuclear bomb, they’d have to turn the country “into one huge factory.” And they all but did. At its peak, the Manhattan Project employed 130,000 people across several major sites. At Los Alamos in New Mexico the Army took over 54,000 acres, some of which was land where Pueblo Indian tribes had held ceremonies for centuries. And although the Pueblo nation members could not access the land directly anymore, many continued to live near the site while the atomic bomb was being built. 

In 1944, the year before Aggie joined the project, quantities of plutonium large enough to be seen by the naked eye were collected on site for the construction of the bomb. As the head of the Manhattan Project’s medical team put it, “The chief concern of the health group was the interpretation of repeated blood counts on exposed personnel.”

One way of monitoring for both acute and chronic radiation exposure is to look for drops in the blood cells produced by the bone marrow – white cells, red cells, and platelets. That’s why monitoring the scientists’ blood was so important. And for that, they needed technicians like Aggie.

Floy Agnes Lee: I had to learn how to take blood, how to read the blood cells, what type of blood cell, and all that's connected with the hematology.

Monica Lopez: Aggie was assigned to certain scientists. One of those scientists was the renowned Italian physicist Enrico Fermi.

Fermi led a group  that was building an experimental nuclear reactor beneath the football field at the University of Chicago. The reactor was called Chicago Pile 1. And as you heard in the previous episode, it was there that Fermi and his team created the first sustained nuclear chain reaction. In 1944, he became an associate director at Los Alamos and stayed for more than a year.

Because of the highly classified nature of  the Manhattan Project, Aggie had no idea who Fermi was when he came to Los Alamos.

Floy Agnes Lee: I only knew him as a number because they wouldn't give names out. And we got to talking, and we got on the subject of tennis. So we would play tennis. 

This was before the bomb was dropped. Anyway, after the bomb was dropped, the GI's who worked at the laboratory came up and shook my hand and said, “You were the person who stuck the hand of the great Enrico Fermi.” I said, “What? “Yes, Enrico Fermi.”

We didn't know that we were working on the atomic bomb except for the physicists. We thought they were doing chemical warfare.

Monica Lopez: But they did know that the work they were doing was dangerous because so little was known about the effects of radiation, and there had already been one death from radiation exposure before Aggie started her work there.

Just how dangerous became clear to Aggie in the aftermath of a second accident with plutonium. It happened nine months after the end of the war as the research into nuclear weapons continued. 

On the afternoon of May 21st, 1946, a group of scientists was gathered around a metallic sphere in a lab at Los Alamos to observe an experiment. The goal was to cause a plutonium core to generate a short controlled nuclear chain reaction.

One of those scientists was Louis Slotin, a 35 year-old Canadian physicist who had performed many experiments with plutonium. But on this day, Slotin’s hand slipped while running the experiment, causing a burst of radiation in the room.

Floy Agnes Lee: And Slotin, he was completely exposed. 

Monica Lopez: Almost immediately, one of Slotin’s hands turned a waxy blue and developed large blisters. He had internal radiation burns. Aggie was part of a team that took his blood in the days that followed. His white blood cell count plummeted. He slipped into a coma. His body, Aggie recalled, started to swell.

Floy Agnes Lee: Slotin began to increase in size. And it was difficult to take his blood. I finally had to get the, take it from the ear.

His mother and father were called because they knew he wasn't gonna live. It was just nine days after the accident, and his parents came and stood in the doorway and looked in and saw him.

Sure enough, the next day he died of radiation poisoning.

Monica Lopez: After the war, Aggie continued working at Los Alamos. At a party one night, before Fermi returned to Chicago, he approached her.

Floy Agnes Lee: He came over and sat with me and he said, and now that the bomb has been dropped, what are you going to do? And I said, well, I want this to go and study more about what radiation does to living cells.

He said, you come to the University of Chicago.

Monica Lopez: And so she did.

Aggie began her PhD studies in zoology at the University of Chicago in 1946, while also working at the Metallurgical Laboratory, which would become Argonne National Lab.

That was where she met – and soon married – fellow scientist Clyde Stroud. But when their daughter was just two years old, Stroud died of cancer.

Yet Aggie was determined to continue her studies.

Floy Agnes Lee: I decided I went to Chicago to get my PhD and I'm gonna get it.

It took me about 14 years to get the PhD, and I was in my forties when I got it. But I did it.

Monica Lopez: Aggie’s interest in the effects of radiation on the human body never waned and became central to her further research. She researched the use of radiation for treating cancer, she saw how it could be used for good.  And in the 1960’s while working at the Jet Propulsion Laboratory in Pasadena, California, she pioneered a method of  analyzing chromosomes using an electron microscope and a computer the size of a large room. 

In the 1970s, Aggie returned to Los Alamos, where it all started, to work in the health research laboratory as a radiobiologist. What motivated her was, in part, personal.

Floy Agnes Lee: I think the worst effect of Los Alamos, not just on the Pueblo, but the surrounding area is the radiation that has caused leukemia. I have four relatives. Two are my sister and my brother died of leukemia. And, a cousin, two cousins have died of leukemia.

So there, I think that the radiation has something to do with it, you know. I have no way of proving that. Or it's just a speculation of radiation is bad.

Monica Lopez: She retired from Los Alamos aged 62.

Floy Agnes Lee: After I retired,  I really retired. I played tennis, I played golf. 

Monica Lopez: Until her eyesight failed. 

Floy Agnes Lee: I had to quit golf because of my eyesight. I couldn't see where the ball went.

Monica Lopez: The interview you’ve been hearing was conducted in 2017, when Aggie was 94. It took place in Santa Fe, where she was living at the end of her life. It’s clear from the interview that she had suspicions about her own health and the effect of having spent years examining living cells for radiation. 

Floy Agnes Lee: I have a feeling that perhaps maybe the exposure to all that light coming from radioactive material and the light from the microscope had something to help develop my blindness.

Monica Lopez: Aggie also made it clear in that interview from six years ago that although she was all too aware of a nuclear weapon’s destructive power, she didn’t doubt that the atomic bomb had to be built – and used. As it turned out, that pivot at an early age, from a dream of flying airplanes to the Manhattan Project, came to define the rest of her life.

Dr. Floy Agnes Lee, determined student and accomplished research scientist, died on March 6, 2018 at the age of 95. 

Katie Hafner: This has been Lost Women of the Manhattan Project. Monica Lopez produced this episode, with help from Deborah Unger, Mackenzie Tatananni, and Danya AbdelHameid.

Lizzy Younan composes our music and Paula Mangin creates our art. Thanks to Amy Scharf, Jeff DelViscio, John Marks, Eowyn Burtner, Lauren Croop, Molly Alexander, Carla Sephton, Sophia Levin, Jeannie Stivers, and to the folks at Los Alamos National Laboratory who are helping us snatch the story of the women who worked on the Manhattan Project from the jaws of historical obscurity. Lost Women of Science is funded in part by the Alfred P. Sloan Foundation and Schmidt Futures. We’re distributed by PRX and produced in partnership with Scientific American. For more about Lost Women of Science, please visit us at lostwomenofsicence.org. And think about hitting that donate button. I’m Katie Hafner.

Speaker: Juanita Wagner.

Speaker: Rosa Curtis.

Speaker: Melba Johnson.

Speaker: Kay Manley.

Speaker: Alice Martin.

Speaker: Laura Fermi.

Speaker: Margaret Keck.

Speaker: Donna Robinson.

Speaker: Beverly Lewis.

Speaker: Dorothy Wallace.

Speaker: Mary Parrish.

Speaker: Eleanor Rees.

Katie Hafner

Host & Executive Producer

Katie Hafner was a longtime reporter for The New York Times, where she continues to be a frequent contributor. Katie is uniquely positioned to tell the stories of lost women of science. Not only does she bring a skilled hand to complex narratives, but she has been writing about women in STEM for nearly 30 years. She is the author of six books of non-fiction, and her first novel, The Boys, was published in July 2022 by Spiegel & Grau. Katie is also the host and executive producer of Our Mothers Ourselves, an interview podcast that celebrates extraordinary mothers.

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