Secret World War II Chemical Experiments Tested Troops By Race While the Pentagon acknowledged years ago that it used American servicemen in World War II mustard gas experiments, NPR found new details about tests that grouped subjects by the color of their skin.

Secret World War II Chemical Experiments Tested Troops By Race

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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.

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