Secret World War II Chemical Experiments Tested Troops By Race

Jun 22, 2015
Originally published on June 24, 2015 12:05 pm

As a young U.S. Army soldier during World War II, Rollins Edwards knew better than to refuse an assignment.

When officers led him and a dozen others into a wooden gas chamber and locked the door, he didn't complain. None of them did. Then, a mixture of mustard gas and a similar agent called lewisite was piped inside.

"It felt like you were on fire," recalls Edwards, now 93 years old. "Guys started screaming and hollering and trying to break out. And then some of the guys fainted. And finally they opened the door and let us out, and the guys were just, they were in bad shape."

Edwards was one of 60,000 enlisted men enrolled in a once-secret government program — formally declassified in 1993 — to test mustard gas and other chemical agents on American troops. But there was a specific reason he was chosen: Edwards is African-American.

"They said we were being tested to see what effect these gases would have on black skins," Edwards says.

An NPR investigation has found evidence that Edwards' experience was not unique. While the Pentagon admitted decades ago that it used American troops as test subjects in experiments with mustard gas, until now, officials have never spoken about the tests that grouped subjects by race.

For the first time, NPR tracked down some of the men used in the race-based experiments. And it wasn't just African-Americans. Japanese-Americans were used as test subjects, serving as proxies for the enemy so scientists could explore how mustard gas and other chemicals might affect Japanese troops. Puerto Rican soldiers were also singled out.

White enlisted men were used as scientific control groups. Their reactions were used to establish what was "normal," and then compared to the minority troops.

All of the World War II experiments with mustard gas were done in secret and weren't recorded on the subjects' official military records. Most do not have proof of what they went through. They received no follow-up health care or monitoring of any kind. And they were sworn to secrecy about the tests under threat of dishonorable discharge and military prison time, leaving some unable to receive adequate medical treatment for their injuries, because they couldn't tell doctors what happened to them.

Army Col. Steve Warren, director of press operations at the Pentagon, acknowledged NPR's findings and was quick to put distance between today's military and the World War II experiments.

"The first thing to be very clear about is that the Department of Defense does not conduct chemical weapons testing any longer," he says. "And I think we have probably come as far as any institution in America on race. ... So I think particularly for us in uniform, to hear and see something like this, it's stark. It's even a little bit jarring."

NPR shared the findings of this investigation with Rep. Barbara Lee, D-Calif., a member of the Congressional Black Caucus who sits on a House subcommittee for veterans affairs. She points to similarities between these tests and the Tuskegee syphilis experiments, where U.S. government scientists withheld treatment from black sharecroppers in Alabama to observe the disease's progression.

"I'm angry. I'm very sad," Lee says. "I guess I shouldn't be shocked when you look at the syphilis studies and all the other very terrible experiments that have taken place as it relates to African-Americans and people of color. But I guess I'm still shocked that, here we go again."

Lee says the U.S. government needs to recognize the men who were used as test subjects while it can still reach some, who are now in their 80s and 90s.

"We owe them a huge debt, first of all. And I'm not sure how you repay such a debt," she says.

Mustard gas damages DNA within seconds of making contact. It causes painful skin blisters and burns, and it can lead to serious, and sometimes life-threatening illnesses including leukemia, skin cancer, emphysema and asthma.

In 1991, federal officials for the first time admitted that the military conducted mustard gas experiments on enlisted men during World War II.

According to declassified records and reports published soon after, three types of experiments were done: Patch tests, where liquid mustard gas was applied directly onto test subjects' skin; field tests, where subjects were exposed to gas outdoors in simulated combat settings; and chamber tests, where men were locked inside gas chambers while mustard gas was piped inside.

Even once the program was declassified, however, the race-based experiments remained largely a secret until a researcher in Canada disclosed some of the details in 2008. Susan Smith, a medical historian at the University of Alberta in Canada, published an article in The Journal of Law, Medicine & Ethics.

In it, she suggested that black and Puerto Rican troops were tested in search of an "ideal chemical soldier." If they were more resistant, they could be used on the front lines while white soldiers stayed back, protected from the gas.

The article received little media attention at the time, and the Department of Defense didn't respond.

Despite months of federal records requests, NPR still hasn't been given access to hundreds of pages of documents related to the experiments, which could provide confirmation of the motivations behind them. Much of what we know about the experiments has been provided by the remaining living test subjects.

Juan Lopez Negron, who's Puerto Rican, says he was involved in experiments known as the San Jose Project.

Military documents show more than 100 experiments took place on the Panamanian island, chosen for its climate, which is similar to islands in the Pacific. Its main function, according to military documents obtained by NPR, was to gather data on "the behavior of lethal chemical agents."

Lopez Negron, now 95 years old, says he and other test subjects were sent out to the jungle and bombarded with mustard gas sprayed from U.S. military planes flying overhead.

"We had uniforms on to protect ourselves, but the animals didn't," he says. "There were rabbits. They all died."

Lopez Negron says he and the other soldiers were burned and felt sick almost immediately.

"I spent three weeks in the hospital with a bad fever. Almost all of us got sick," he says.

Edwards says that crawling through fields saturated with mustard gas day after day as a young soldier took a toll on his body.

"It took all the skin off your hands. Your hands just rotted," he says. He never refused or questioned the experiments as they were occurring. Defiance was unthinkable, he says, especially for black soldiers.

"You do what they tell you to do and you ask no questions," he says.

Edwards constantly scratches at the skin on his arms and legs, which still break out in rashes in the places he was burned by chemical weapons more than 70 years ago.

During outbreaks, his skin falls off in flakes that pile up on the floor. For years, he carried around a jar full of the flakes to try to convince people of what he went through.

But while Edwards wanted people to know what happened to him, others — like Louis Bessho — didn't like to talk about it.

His son, David Bessho, first learned about his father's participation as a teenager. One evening, sitting in the living room, David Bessho asked his dad about an Army commendation hanging on the wall. David Bessho, who's now retired from the Army, says the award stood out from several others displayed beside it.

"Generally, they're just kind of generic about doing a good job," he says. "But this one was a bit unusual."

The commendation, presented by the Office of the Army's Chief of the Chemical Warfare Service, says: "These men participated beyond the call of duty by subjecting themselves to pain, discomfort, and possible permanent injury for the advancement of research in protection of our armed forces."

Attached was a long list of names. Where Louis Bessho's name appears on Page 10, the list begins to take on a curious similarity. Names like Tanamachi, Kawasaki, Higashi, Sasaki. More than three dozen Japanese-American names in a row.

"They were interested in seeing if chemical weapons would have the same effect on Japanese as they did on white people," Bessho says his father told him that evening. "I guess they were contemplating having to use them on the Japanese."

Documents that were released by the Department of Defense in the 1990s show the military developed at least one secret plan to use mustard gas offensively against the Japanese. The plan, which was approved by the Army's highest chemical warfare officer, could have "easily kill[ed] 5 million people."

Japanese-American, African-American and Puerto Rican troops were confined to segregated units during World War II. They were considered less capable than their white counterparts, and most were assigned jobs accordingly, such as cooking and driving dump trucks.

Susan Matsumoto says her husband, Tom, who died in 2004 of pneumonia, told his wife that he was OK with the testing because he felt it would help "prove he was a good United States citizen."

Matsumoto remembers FBI agents coming to her family's home during the war, forcing them to burn their Japanese books and music to prove their loyalty to the U.S. Later, they were sent to live at an internment camp in Arkansas.

Matsumoto says her husband faced similar scrutiny in the military, but despite that, he was a proud American.

"He always loved his country," Matsumoto says. "He said, 'Where else can you find this kind of place where you have all this freedom?' "

NPR Investigations Research Librarian Barbara Van Woerkom contributed reporting and research to this investigation. NPR Photo Editor Ariel Zambelich and reporters Jani Actman and Lydia Emmanouilidou also contributed to this story.

Copyright 2018 NPR. To see more, visit


We have news this morning of a startling episode in U.S. history. It's a moment when the United States military experimented on its own troops with mustard gas.


It happened during World War II. The U.S. was trying to prepare for any possible gas attacks by the Axis powers. And for many years now, the U.S. has acknowledged those experiments on unknowing Americans.

INSKEEP: What we have today are even more troubling details from an NPR News investigation. The World War II experiments exposed African-American, Japanese-American and Puerto Rican troops to chemical weapons.

GREENE: And they sought to find racial differences that could be exploited on the battlefield. NPR's Caitlin Dickerson reports.

CAITLIN DICKERSON, BYLINE: Rollins Edwards grew up in the segregated South. He says like a lot of black boys his age in Summerville, S.C., he was only allowed to go to school through the seventh grade. So when he was drafted into the U.S. Army at 21, it was a big opportunity. The year was 1944.

ROLLINS EDWARDS: I'm glad I served and I appreciate - well, I don't appreciate what they did - hell, no, I don't - but everybody don't get a chance to serve their country.

DICKERSON: After basic training, Edwards was enrolled in a secret program to test the effects of mustard gas on humans. The testing was brutal. Some days, he says he was locked inside of a wooden gas chamber with about a dozen other black soldiers. A mixture of mustard gas and a similar agent called Lewisite were piped inside.

R. EDWARDS: That's when everybody went crazy. It just felt like you were on fire sure enough. And the guys started screaming and hollering and trying to break out. And then some of the guys fainted and finally opened the door and let us out and the guys were just - they were in bad shape because they just couldn't control themselves.

DICKERSON: Edwards says he didn't have a choice. He had to participate. And if he told anyone about the experiments, his commanding officer said he'd go to prison.

R. EDWARDS: They said we were being tested to see what effect these gases would have on black skins. Now if that ain't the damnedest thing I ever heard.

DICKERSON: The U.S. military tested more than 60,000 World War II troops in secret experiments. These tests were formally declassified in 1993. Now, an NPR investigation has found new details about a set of these experiments. Documents show the military scientists thought people with darker skin might be more resistant to chemical weapons, and they tested that theory on black and Puerto Rican soldiers. This was a time when military officials were worried that the German or Japanese armies would use mustard gas on Americans. Experts NPR spoke with say it appears the military hoped troops with darker skin would make ideal chemical soldiers. So if they were more resistant, they could be put on the front lines. According to family members, Japanese-American subjects were told they were being tested as proxies for the Japanese enemy. Now details of these experiments first surfaced in an academic journal article in 2008, but it received little attention. Until now, the military has never acknowledged these race-based tests, and for the first time, NPR tracked down some of the test subjects and their families.

DAVID BESSHO: It may have been something I noticed hanging up there for a while, but I remember it was probably in an evening in the TV room.

DICKERSON: David Bessho was a teenager when he decided to ask his dad about a commendation from the U.S. Army that was hanging on the family's living room wall.

BESSHO: Because I noticed it was a little bit unusual saying that he volunteered to be exposed to chemical agents.

DICKERSON: The award was presented with a list of names. Bessho's father appears on page 10, followed by a curious similarity - Tanamachi, Kawasaki, Higashi, Sasaki. Forty Japanese-American soldiers are named in all.

BESSHO: I just took that occasion to say, hey, what is this about? And he just responded that, yeah, they were looking for Japanese-Americans to make sure the chemical agents had the same effect on Japanese as they did on white people. I guess they were contemplating potentially having to use them against the Japanese.

DICKERSON: White Americans were used in these experiments. They served as control groups. Their reactions were used to establish what was, quote, "normal" and compared to the minority soldiers, like Juan Lopez Negron, who's Puerto Rican. He says he was used as a test subject in experiments known as the San Jose Project.

JUAN LOPEZ NEGRON: (Through interpreter) There was a siren, and then you had to get under a tree to protect yourself. Check your mask, and get ready.

DICKERSON: He says he and the other test subjects - all of them Puerto Rican - were sent out into the Panamanian jungle, and they were sprayed with mustard gas out of U.S. military planes flying overhead.

NEGRON: (Through interpreter) We had uniforms on to protect ourselves, but the animals didn't. There were rabbits, and they all died.

DICKERSON: Military documents found by NPR show more than 100 experiments were done on San Jose Island. The location was chosen for its climate, similar to islands in the Pacific. Not all of those experiments focused on race, but the U.S. government does have a history of race-based experimentation. The most infamous were the Tuskegee syphilis experiments, where treatment was withheld from black sharecroppers so researchers could watch the disease. Dorothy Roberts is a professor of bioethics at the University of Pennsylvania Law School. When told about race-based experiment with mustard gas, she pointed to similarities between the Tuskegee subjects and the minority soldiers used in these tests.

DOROTHY ROBERTS: They were expendable, disposable, allegedly because of their biological difference. But it mirrors, in all of these cases, their social and political status in U.S. society at the time.

DICKERSON: Black, Puerto Rican and Japanese-American soldiers were all confined to segregated units during World War II. They cooked, cleared trash, drove dump trucks and many felt they had to prove themselves.

SUSAN MATSUMOTO: I think lot of our Japanese boys had to.

DICKERSON: Susan Matsumoto's husband, Tom, was another one of the men used. Tom died in 2004. Matsumoto and her family were forced to live in an internment camp during the war. But she says even though her husband was tested as a proxy for the enemy, he was a proud American.

MATSUMOTO: He always loved this country. He said where else can you find this kind of place where you have all this freedom?

DICKERSON: Congresswoman Barbara Lee is a member of the Congressional Black Caucus and sits on a House subcommittee for Veterans Affairs. We showed Lee some of the documents related to these tests.

CONGRESSWOMAN BARBARA LEE: Let me read you a quote from the Army's report. Quote, "It has been suggested that the relative resistance of Negroes may be related to the relatively thick horny layer of their skin." Now that's an official Army report. That's outrageous.

DICKERSON: Now to be clear, horny layer is a technical term. It's a layer of skin that everyone has. It's not thicker in African-Americans. And dermatologists NPR spoke with say that statement by the U.S. government is not scientifically sound.

LEE: We owe those who are still alive, and the families, we owe them a huge debt, first of all. And I'm not sure how you repay such a debt.

DICKERSON: Mustard gas reacts with human DNA within seconds of making contact, causing irreversible damage to the cells. Exposure can lead to life-threatening illnesses, like skin cancer, leukemia, emphysema or asthma. At 93, Rollins Edwards hasn't faced any of those diseases, but he's had decades of pain and discomfort because of the experiments. His arms and legs are covered with thick scabs the size of pancakes, and he scratches them until they bleed.

Your arms bothering you this morning?


DICKERSON: Edwards still lives in Summerville, S.C., the town where he grew up. He's been active in a local chapter of Prince Hall Freemasons for years. During outbreaks, he's had to wear gloves so he could shake hands with people.

R. EDWARDS: My hands would get so bad I couldn't even wash my hands. And they would actually stink.

DICKERSON: Little bottles of lotion and aloe are scattered all over the house so his wife, Juanita, can try to soothe him when the scabs flare up.

JUANITA EDWARDS: You got to take the jacket off and your shift loose for me.


DICKERSON: His skin falls off in flakes that pile up on the floor. For years, he carried around a jar of those flakes to try to convince people of what happened to him. Until now, government officials have never acknowledged these experiments.

COL. STEVE WARREN: The first thing to be very clear about is that the Department of Defense does not conduct chemical weapons testing any longer.

DICKERSON: That Army Col. Steve Warren. He's the Pentagon's top spokesman, and he says these experiments are difficult to even fathom today.

WARREN: The idea of conducting racially-based experiments, it is just not something that we would even consider. Doesn't enter the thought process.

DICKERSON: Col. Warren struggled to come up with a reason why the U.S. military would've done this.

WARREN: It was a terrible, terrible, terrifying time. I don't know that Americans knew what was next as they saw the Japanese and the Germans encircling the world. Everyone had to do their part, and in many cases, a lot was asked.

DICKERSON: He says he thinks all Americans struggle with some of the choices made during that time. Caitlin Dickerson, NPR News.

INSKEEP: By the way, the Department of Veterans Affairs promised more than 20 years ago to provide benefits to veterans injured in mustard gas experiments. And later this week, we will look into the keeping of that promise.

UNIDENTIFIED MAN: This is a bargain we made, and this goes to the essence of can you trust your government? And in this case, I'm afraid the answer is not yet. Transcript provided by NPR, Copyright NPR.