Radiolab - The Smell of Hell

Episode Date: October 16, 2026

Throughout human history, there’s been one element we’ve always associated with death. Just the smell of it is an alarm bell that says, “something here is dangerous.” But what if our noses have been wrong all along?In this episode of our series Viscera: Gripping Tales of the Human Body, we take you to a live performance in Boston where we reveal how this much-maligned element might be better understood as the smell of life.LATERAL CUTS:Want to see a Viscera show? Join us for Radiolab Presents: Viscera, live in New York City on Thursday, November 5th. All about the sometimes freaky world of organ transplants, with special guest Mary Roach discussing her upcoming book, Replaceable You: Adventures in Human Anatomy. Get your tickets at wnyc.org/events.EPISODE CREDITS:Reported by - Avir Mitra and Matt Kieltywith help from - Mona MadgavkarProduced by - Mona Madgavkar and Matt Kieltywith mixing help from - Jeremy BloomFact-checking by - Rachel Grossand Edited by  - Pat WaltersLiveshow production support - Natalia Ramirez, Sarah Sandbach, Maia Appleby Melamed, and Jeremy Bloom.EPISODE CITATIONS:Videos - Watch the video of Radiolab Presents: Viscera live at WBUR CitySpace (https://zpr.io/PZF3BqnbKKJD)Articles - A possible chemical explanation for the events associated with the death of Gloria Ramirez at Riverside General Hospital (https://zpr.io/sbjXYcPenGSH), the paper explaining Livermore Lab’s hypothesis.Books - The Great Secret (https://zpr.io/PGCmihSFBHj4), by Jennet Conant about the birth of chemotherapy in the laboratory of war. Signup for our newsletter!! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up (https://radiolab.org/newsletter)!Radiolab is supported by listeners like you. Support Radiolab by becoming a member of The Lab (https://members.radiolab.org/) today.Follow our show on Instagram, Twitter and Facebook @radiolab, and share your thoughts with us by emailing [e-mail] support for Radiolab’s science programming is provided by the Simons Foundation and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.  Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

Wait, you're listening. Okay. All right. Okay. All right. You're listening to Radio Lab. Radio Lab. From WNY.

C. See? Yeah. Hey, I'm Molly Webster. I'm Matt Kilty. This is Radio Lab. And I have a cold. And I don't know what we're doing.

Well, come along, Molly. You're in for quite a treat. So, a little while back. Mm-hmm. This thing started. Who is ready to do? for Radio Lab. Avir Dr. Avere Mitra.

Doctor of Radio Lab, yeah. Regular correspondent. A little while back, we went to Boston. Hello, everybody. I did a live show there. WBR at City Space. And I'm Avere Mitra of Radio Lab correspondent. They're very cool, big performance space.

Got it. All for coming out for our live taping of our Radio Lab series, Visera, Gripping Tales from the Body. Yes. And it's a show about one, single element. Like on the periodic table element. Yes, exactly.

An element that is going to be the theme of our show tonight. I'm not going to tell you what it is, yeah. But that element, it's one of these things that when Avere and I started talking about doing this, we realize it like it is one of the most underappreciated, kind of forgotten elements. Underrated. Underrated. That most people just associate with like disgusting, gross, awful, smelly things. Okay.

We're going to do a few stories to hopefully show you that this element that can induce vomiting. That, in fact, it is a beautiful, beautiful, incredible thing that might be vital to our existence here on Earth. So, Molly, today I thought what we would do is I would play for you this Boston show. Okay. And just because I think it's like a pretty cool collection of stories that basically shine a spotlight on this overlooked maligned element. A maligned element that makes me vom. Let's get it. Fantastic.

All right. let's begin. So we're going to begin with a little mystery story. Yeah, that's right. If I didn't mention it before, Avere is an ER doctor. Yeah, so, you know, as an ER doctor, the question I get pretty much anytime I'm in a group setting is like, dude, what's the craziest thing you've ever seen in the ER?

So I'm almost trying to think of answers. But, you know, since I hugely respect patient privacy, HIPAA, and my retirement savings account, I'm not going to tell you the craziest thing I've seen, but I think I've found the craziest thing that's happened in an ER like ever. Do you guys want to hear that story? All right, here we go. So this story starts February 19th, 1994 in an ER in Riverside, California.

A patient shows up by the name of Gloria Ramirez, a young woman. She's just 31 years old, mother of two. And she had just been diagnosed with metastatic cancer, hadn't even started treatment. yet. So she arrives in the ER and she's delirious. She's sweaty. She looks so sick and her vital signs are crashing. And so the ER team jumps into action right away as we do. They start bagging her with oxygen. They put the paddles on her, turn it all the way up. They shock her. None of it's working. Of course, the nurse comes up to draw some blood. So she puts the needle in the vein. Blood starts working its way into the tube. The nurse takes the tube and passes it to the resident doctor

behind her. And next thing you know, this nurse passes out, falls to the ground unconscious. The resident doctor holding the tube starts to feel these crazy sensations burning on her face, skin tingling, nausea, lightheadedness, and then she passes out, falls to the ground, unconscious. The respiratory therapist who's bagging the patient with oxygen, she gets wobbly, unconscious, falls to the ground. So it's three people down. Yeah, exactly. And of all the people in the ER, there were 37 people in the ER, there were 37 people in the ER that night, within a few minutes, 23 of them start experiencing these weird symptoms, nausea, tingling,

burning of their skin. The incident that hospitalized six medical workers, including one doctor, was so alarming to the staff at Riverside General Hospital that the emergency room was evacuated to the parking lot. So the hazmat team arrives, they go get all gowned up, go through the hospital, search every pipe, all the machines, trying to find some sort of gas leak, maybe there's carbon monoxide,

maybe something, but they're, They find nothing. And so now the ER staff is stuck outside in the parking lot trying to deliver medical care, and they're all talking amongst themselves thinking, like, what the hell just happened? Yeah. And so they all start to say, well, you know, this all started right around when Gloria Ramirez appeared in the ER. What if this had something to do with Gloria? Investigators are speculating that the workers may have been exposed to a toxin used in pesticides,

or that Ramirez took a suicidal dose. of some poison, but family members disagree. She didn't have the energy to even walk to the bathroom, let alone go look for the, look for any type of pesticide or anything to drink. While all this chaos is going on in the parking lot, a skeleton crew of doctors had actually stayed inside the ER to try and save Gloria, but she did ultimately die that night. So the next step is they conduct an autopsy. The autopsy was done in an airtight plywood chamber built inside the

coroner's office. The people who performed the operation wore hazardous material suits and were hosed down with decontaminants when it was over. Ultimately, after this autopsy, what they found is that Gloria died of kidney failure. Which is weird. Kidney failure doesn't mean like people start passing out. Exactly. So the mystery remained. So at this point, the state of California got involved. They decided to conduct their own investigation. They interviewed everyone, went through all the documents and after months and months, they came out with this theory. This was probably an episode of mass hysteria. That's what they decided. Shared stress. Right. And their reasoning was, you know, look, a lot of the people that passed out, they were women. Oh. This is in the report.

I didn't write the report. This is in a virus. No, I didn't write this. You know, they hadn't taken a lunch break. You know, they're saying they were under a lot of stress. Yeah, you know, I'm always passing out when I don't eat lunch. It's so weird. So, yeah, as you can imagine, like, nobody who worked at this hospital was happy with this. You know, why, you know, these nurses, if you know any ER nurses, they are some of the most grisly seasoned people you could ever meet. We never get lunch breaks.

Like, why would we all of a sudden have this episode of mass hysteria just makes no sense? And even Gloria's family, they weren't happy with this either. It didn't make much sense. So ultimately, they decided to do. a second autopsy. And this autopsy, they send to a pretty fancy lab at the Livermore Labs in San Francisco. And they do something that's not typical for an autopsy. They do something called gas chromatography. So what that is, is they basically take samples of glorious tissues, all the different tissues in her body, and they basically melt away the solid till there's only liquid left.

They burn that liquid. And depending on the color at which it burns and the temperature at which burns, you can kind of get a sense of what's in there. So it's a really good way of looking at a very molecular chemical level of what's going on inside of Gloria. What would Ramirez's blood reveal? Every peak here is a different, unique chemical that was in the blood of Mrs. Ramirez. And things stand out is very obvious. This is all Tylenol or acetaminophen is right here. Cholesterol is here, other drugs, and a very unusual chemical we initially discovered, which was right here. We don't know what it is at this moment,

but luckily we have libraries when you actually search a library in the computer, it will print out what this chemical is. Whatever could our mystery chemical be? I'm so glad you asked. That was the theme of the night. Sulfur.

Oh, that's our mystery element. This is the element, the theme, the theme of the show, the theme of the night. I associate sulfur with like the environment. Like, I didn't know we could have sulfur in us. Yeah, so it turns out it's a specific type of sulfur called DMSO2. Okay. Now, the interesting thing about DMSO2 is you can find DMSO2 in the human body

because if you eat like asparagus or some raw milk, you can get some DMSO2 into your body. Oh, is that why asparagus makes your pee smell funny? Oh, that's a good question. Don't know. But the amount of DMSO2 that seemed to be in Gloria seemed to be way higher than you could, like, otherwise predict. So they're confused. Like, this isn't normal. Could there be a clue in here?

And so they think and they realize there's a related chemical to DMSO 2 called DMSO. Now DMSO completely different is an industrial degreaser. Wait, what is a de-greaser? It's just like often a spray, you put it on greasy stuff

to cut through the grease, clean things. Wait, why was she using a degreaser on her body? So potentially pain relief. It turns out back in the day and for decades, have used this medicinally. People used to rub this like a bomb on their heads when they had headaches or rub it on their joints if they have joint pain. It's like an old school icy hot. Yeah, exactly. Since fallen out of favor, but people still use this off label. So they start to think,

wait, what if Gloria having cancer, having all this pain may have been using DMSO? And the only difference between DMSO and DMSO2 is a little bit more oxygen. So maybe that DMSO turned into DMSO2. But the problem is neither DMSO or DMSO2 are toxic. So they got to go back to the drawing board. They find another related chemical

called DMSO4. So DMSO4 also related. But the interesting thing about this chemical is this was experimented on as a toxic gas agent. And guess what the symptoms were? Nausea, burning of the skin, fainting.

Lightheadedness, fainting, and in enough dose you could even die. So they think, well, wait, what if Gloria had been using DMSO on her skin for her aches and pains came into the ER, was getting bagged full of oxygen, which converted some of that DMSO into DMSO 2? And then something crazy would have had to happen. A lot of energy would have to go into this to turn DMSO2 into DMSO4, something like turning a defibrillator up to 360 joules,

and shocking her. And then all that need to happen is a nurse comes up to draw some blood, just to drop a blood on the skin, could release enough fumes to cause all the symptoms that we saw in the ER that night. So it's like, woman comes in the ER turns into chemical weapon.

That's the theory. But the truth is, there's a lot of issues. While these things can happen in a test tube, no one has ever shown that this could actually happen in a human body. It's also insane. It's also insane. That's number two.

Number three. Gloria's family, to this day, denies that she ever heard about or used DMSO. And so at the end of the day, the state of California has always stuck with the idea that this is an episode of mass hysteria. While the Livermore Labs states the most likely thing was an airborne toxic event. And the truth is, I think this will always remain a mystery. I don't think we will ever know what really happened that night. But there is one thing that we do know from that night, which is that the medical staff who treated Gloria

reported smelling an odor in the room. Now, you all have a brown paper bag. If you open up that bag, you will find a Ziploc bag with a green dot on it. So we had everybody, we had given them bags with little perfume blotter strips. Okay. We had basically had a perfumer make a lot of different sense

that we were going to use throughout. night. And so we had them pull out this one blotter strip. That's what we call blotter strip. Take that out. Wafed it a little bit. What are we smelling out there? Garlic? We're hearing some garlic? She said specifically Italian garlic. Okay. Love. I'm into it. It's like, but it's really pungent. It's like actually very sharp. It's kind of harsh. And what is interesting is that one of the few things that we can definitively say about what happened that night is that people in the ER, when Gloria Ramirez arrived, reported smelling something sort of garlicky.

Okay, okay. So you are smelling, you are smelling that garlic you smell. Now, this is the important part about it, is that what makes up a lot of that scent is a sulfur compound, which some people say it's a confirmation that, in fact, this crazy transformation had taken place that night. But it doesn't necessarily answer everything because it also sort of supports this idea that the state of California was presenting,

which is that that smell, in and of itself was kind of this like inciting event, an event that would cause this fear to ripple through an entire staff because the thing about sulfur is that we have evolved to be kind of terrified of it. In fact, like, maybe of all the elements, it's the one that we are most terrified of because we are incredibly attuned to it. Our nose can pick up some sulfur compounds at as little as 0.5 parts per billion in the air.

and if that doesn't mean anything to you, which might not. If you were to imagine like 8 billion people of Earth all squish together, that'd be the equivalent to be able to pick out four individuals inside that massive humanity. Like that's how sensitive we are. And we've evolved to be that sensitive because sulfur is death. It is rot. It is decay. When you die, when bacteria starts eating your flesh, your organs, they start pumping out sulfur.

And that idea has woven itself into culture. Fire and Brimstone. Brimstone is just an archaic way of saying sulfur. Like, this is what we call hell. And in fact, you know, like, when you smell it, we've been evolved to smell it so that it's like a little alarm for us. It's like, something's happening. So, like, when you cook with natural gas, you know, natural gas is actually odorless, they pump sulfur into the gas so that you can detect any faint leak inside your house. It tells you something here is terribly, terribly wrong.

Hmm. Or does it? So to pick apart that question, we're going to welcome out to the stage, author, historian, Jeanette Cohnent. Okay, Jenny, thank you so much. All right, so Jenny wrote this fantastic book, The Great Secret.

And I remember when we first spoke, you had a personal connection to how this all began for you. Yeah, I was writing a book about my grandfather, James P. Conan, and he was the brilliant chemist, president of Harvard, and one of the famous warrior scientists of World War II, he was tapped by President Roosevelt to head the Manhattan Project,

and he was Oppenheimer's boss. He personally oversaw the development of the bomb. Anyway, I finished the book, and I found a really weird fact. After the war, he went on the board of a big hospital, which was weird. He just built a weapon of mass destruction. He really wasn't a warm and cuddly guy. But why a hospital?

So I did some research, and I found a crazy story about the Bari disaster, and it became my next book. Yeah, okay, so let's start that. Bari. Where exactly are we? When are we? So this picture, this is a Nazi photograph, aerial photograph. This is probably taken about the time of the book, which is December 2nd, 1943. I was born in December 2nd. And Bari is a huge Italian harbor on the age of the age of the second. Coast, and it was a major staging area for the planned invasion of France at the Normandy Beachhead. And it was just full of British and American ships. The Allies were relying on this to supply their troops. There had to be like 30 Allied ships packed in there, like sardines lined up one after another.

And there were nine enormous American Liberty ships, and they were carrying all kinds of vital supplies from, you know, ammunition, weapons. fuel oil. All preparing for like the invasion that's about to happen. Yeah, D-Day. And as we've already stated, this is a Nazi aerial photograph. Yeah. So unfortunately for us, the Nazis figured this out. And that night on December 2nd,

they launched a devastating air raid on Bari. And they rained bombs down on the anchored ships, which couldn't escape. So it was just horrific. One ship after another blew up within a matter of, minutes the whole harbor was consumed by thick black smoke and flames. And the surviving crew members had no choice but to jump overboard like a sea of fire and they just swam for it. And, you know, it was just horrible. It was a huge success for the Nazis. They killed a thousand sailors in one

night. They wounded that many. They sunk at least 17 ships. And who knows how many, many civilians were affected. And so the press immediately dubbed the disaster the Little Pearl Harbor. Huh. You said a thousand people are killed. So what comes after this? Well, what the press didn't know was in the next 24 hours, the scope of the disaster would widen horribly

because they plucked hundreds of these young sailors from the water. And they did what, you know, it was a British harbor. The British did what they usually did. disaster. They wrapped them in warm blankets. They gave them strong sweet tea, and they kept them comfortable until the ER doctors, who had run off their feet that night, could take a look at their wounds and their blast injuries. But, you know, very quickly it became apparent that these sailors didn't have the usual blast injuries. And instead of responding well to treatment, they took a turn for the worse. Then by the next morning,

It was really alarming because they had developed blisters the size of balloons. Their eyes had swollen shut. And they had all these really strange delayed symptoms like extreme nausea and vomiting. None of this was normal. And they didn't really know what to do. And in fact, they just labeled all of the injuries a dermatitis NYD, which meant not yet diagnosed. And, you know, within 12 to 48 hours, 12 men had died. And within three days, the wards were filled of hundreds of sailors who were blind and screaming in pain and panicked.

And at that point, the British doctors knew that they were dealing with something really out of the ordinary. And they began to suspect that among the incendiary bombs, the Germans maybe had used some diabolical chemical weapon. Okay, we're going to pause right here because yet again, this is an opportunity for you to smell something. At this point in the show, we had the audience smell. What you are all smelling right now is mustard gas. Mustard gas. Wait, you can do that? Well, we, I kept trying to tell him it was mustard gas.

You're all smelly mustard gas. This will be our last radio lab performance ever. It's not actually mustard gas. It's again, it's like a perfumer made a scent based on the description of survivors of mustard gas attacks. I'm just like thinking about the candle company that you would. Yanky mustard gas. Yeah, but I mean, it was really terrible stuff. It was used a lot in World War.

World War I was called the Chemist War. The Germans' favorite weapon was chemical, poison gas, biological weapons, everybody's worst nightmare, accounting for over a million casualties in World War I. And as a result, everyone decided to ban it in the Geneva Protocol of 1925. This is too terrible to use. Too terrible. The cost was too high.

No one wanted to see it again. Unfortunately, neither Churchill nor Roosevelt really believed that the Germans wouldn't use it again. It had been their favorite weapon. They had made tons of it. They had tons of it. And they were afraid that if the war went badly and Hitler's back was to the wall, he would resort to using chemical weapons again. So the Allies had no choice but to study it, make it, and work on antidotes. General Eisenhower, who is head of the Allied forces in Europe,

he insisted on having a chemical warfare expert on his staff, and all of the troops were trained in chemical weapons. They carried little detector kits, and they knew how to smell it. I mean, if you caught a whiff of horseradish or something that tickled your nose in the air, it was mustard. If you smelled freshly moan hay, that would be fosgene. So all of the troops kind of knew this, but it wasn't exactly comforting. And then so they call in, they're like, okay, bari, bari happens.

You have soldiers with blisters, and they're like, okay, we're going to investigate this. It's got to be some kind of chemical weapon. But they don't know what, because nobody can recognize it. And the British, you know, they had all the manuals from World War I. They knew what mustard gas looked like, and this isn't looking right. So they don't know. So Eisenhower sends in his chemical warfare expert, a young American doctor called Lieutenant Colonel Stuart Alexander. There he is.

There he is. And he starts walking the wards of Bari Hospital. And right away, you know, the place is reeking of crude oil and black smoke and other chemicals. But he catches a whiff of garlic. And he's pretty sure mustard gas, right? You smelled it. You're not going to forget it. Well, the British go, no way.

It's not mustard gas. There's no mustard in Bari Harbor. The port authorities say, no, we've studied the port. There's no mustard gas. So he doesn't know what to think. The British doctors say, no, we don't recognize these wounds. So he has to take them at their word. So he orders more tests and he orders more autopsies.

But at the same time, he doesn't entirely buy it. He knows the British have very good reason to deny mustard in Bari Harbor. After all, if Hitler has done it, this is going to mean that America and Britain will have to retaliate in kind. Roosevelt and Churchill said they would. and this could trigger an all-out chemical war. So he's got to be dead certain. So he starts investigating the harbor. He studies where all the ships were located.

He does charts of the casualties where most people died. And what happens is he pinpointed the fact that the epicenter of the contamination at Bari was the John Harvey, an American Liberty ship. He can come to only one conclusion. The John Harvey had to be carrying a secret payload of mustard. gas bombs, probably headed for a secret cache near the front so the Allies could use them if they had to. So it was our, it was our mustard gas.

And then a diver that he had ordered to search the harbor floor, finds the fractured shells. The shells are not from a German bomb, which always has a yellow cross, but an M-47, 100-pound American sulfur mustard bomb. This is the great secret. This is the great secret. So the tragic truth is that when the Luftwaffe bombed the Harvey, they bombed our mustard gas shells. We poisoned in effect our own men. So it's a tragic wartime accident.

Even worse is that the nurses, in wrapping the sailors in blankets, they unwittingly trapped the mustard and oil mixture from the harbor water close to their skin, allowing the men to marinate and the poison. So many more died than they needed to, hence the secrecy, the official cover up, the need for denials. Bari could not have happened. There was no mustard gas accident. Nobody could discuss it because the Germans could not find out. So you just cover it up. But then what comes out of that? Well, the thing is, Alexander, by some crazy coincidence, was probably one of the few doctors in the world that had studied the effects of mustard on laboratory animals.

And he had seen something really striking. So he doesn't want all these men to die in vain. So he starts ordering autopsies, and he sees the same striking result in autopsy after autopsy. What he finds is the white blood cell count has virtually vanished. The lymph nodes are shriveled. As he said, it was like they melted away. And more than that, the bone marrow has been completely decimated.

So what he is seeing, in effect, is that mustard gas has, targeted and virtually decimated the body's ability to produce white blood cells. And he is a doctor in peacetime. And what he is wondering is, can this poison in tiny doses be used to attack malignant white blood cells? For example, leukemia, the most common form of childhood cancer is characterized by runaway white blood cell counts. So here's the age-old question. Can a harmful substance heal? We know throughout time

dangerous poisons like arsenic and digitalis are used as drugs. Why not mustard? Interesting. Okay. So he basically has a strange, horrible human experiment in which he can just pull all these results from. He's got a morgue full of dead bodies. Right.

So, okay, so he then does that, writes it up? He writes it up in a classified report and he sends it to his boss, Colonel Cornelius Rhodes, who is head of the chemical warfare division's medical division. But in peacetime, he's head of a big hospital in New York. He immediately recognizes the significance of Alexander's report that it's a landmark study in proving that mustard is a cell poison. And this immediately propels all of the medical efforts to research cancer forward.

There was a group of doctors at Yale that had done a small but very secret study injecting nitrogen mustard, which is a chemical cousin of sulfur mustard. Right, you swap out the sulfur and a nitrogen goes in its place. Into a few human beings, and they had received incredible results. They had managed to shrink tumors in a couple of advanced lymphoma cases. Unfortunately, the patients all relapsed and died, but together with the Bari report and the hundreds of autopsies, Rhodes now had what he felt was proof of mustard gas's curative potential. So this is Cornelius, right? This is him.

Dusty Rhodes to his friends. And I will just say Dusty Rhodes. Medical Savior, also really, really racist guy. Like Beyond the Beyond, yeah. Yeah, bad stuff. But anyways, like, they have this sort of breakthrough with chemical weapons. And then, incredibly, on August 7, 1945, which is the day the world learned that the atom bomb had been dropped up.

on Japan, Rhodes announces that they're going to start a huge hospital in New York and commit like an all-out war on cancer and try and conquer this thus far incurable disease. And he says he's going to recruit all of the chemical warfare experts to help carry out this revolutionary idea of using not just nitrogen mustard, but a whole array of toxic chemicals to attack cancer, and this would pave the way for a modern treatment known today as chemotherapy.

That's crazy. In this full circle, this is how your grandfather shows up on the board. Jenny, thank you so much. This is great. A little round applause here. You can find her book.

Wherever you get books, I'm going to offer to be like this. More on the element of sulfur after the break. Yeah. Sulfur in your head. Oh, sulfur in my head? After the break, in a good way. Yeah.

Okay. I'm in. All right. Back in a minute. We're back. We're back with Sulfur and Matt. And Molly. And Devere.

And Mona. In Boston. Good. Okay. We got one more story. Yeah, one more story. How are you guys doing? Are you doing okay?

One more? Okay. This story is another bad smell. I'm not going to make you smell it. but it's hydrogen sulfide, which is the smell I like to say of the Jersey Turnpike. Yeah, I'm from Jersey, so I can say this. You know, there's a funky smell around Exit 13 on the Jersey Turnpike.

It's kind of the smell of like a sewer, you know, or if you're at the ocean and it's low tide, that kind of swampy smell. That's hydrogen sulfide, also known as swamp gas. All right. The interesting thing about this is that at high enough doses, it can kill you. Not if you're just smelling it on the road,

but like let's say you're doing a 12-hour shift in a sewer or you're drilling for oil. Like if you get enough hydrogen sulfide, you can die. So third story starts in the year 1989 with a scientist named Werenitia. And he wants to be the guy to figure out how does hydrogen sulfide kill? So he takes a bunch of rats, as you do,

and exposes them to, toxic levels of hydrogen sulfide gas. And then he kills the rats, dissects their brains, and looks in there. And what he finds is that, sure enough, there is this swamp gas in their brains.

So that's interesting, fine. But like any good scientist, he has to have like a control group, right? Some rats that didn't get exposed. He kills them, dissect their brains, and he's surprised because he sees a little bit of swamp gas in their brains too.

So he's thinking, all right, Did I mess up my rats? Did some gas leak from here to there? You know, keeps running the experiment over and over. And every time his control rats have a little bit of hydrogen sulfide in their brains. So he publishes his results that pretty much go unnoticed. Not too many people read the paper.

But the few people that do are trying to figure out, well, why are these rats producing hydrogen sulfide? And they sort of just attribute it to, like, best I could describe is brain farts. you know, every engine creates exhaust, right? Every motor creates fumes, and the brain's doing a lot of work. So maybe it's just, you know, creating fumes. It's farting. It's just doing what it does. And so that was sort of the state of play for like 10 years.

That's what people just assumed. Until another scientist came along by the name of Hideo Kumura, Japanese scientist. And he looked at it sort of differently. He said, like, the brain is not just a normal motor. It's way too perfect. It's way too smart. You know, why would a brain just be making farts and marinating in its own farts? He did not like that explanation at all.

She would never do that. She would never do that. So he decides, I want to figure out what hydrogen sulfide is doing. It has to be there doing something. So he decides to study neurons in mice. So as most of you probably know, but the way thoughts and actions and memories happen is neurons, send messages to other neurons. Brain is just full of neurons, right?

And so for something to happen, a neuron has to get a signal, pass that signal to another neuron, pass it to another neuron, and that becomes an action or a memory or a thought, right? So he's studying these connections between neurons, and he's realizing that the more a particular path of neurons gets activated by a particular repetitive thought or repetitive action,

the more those neurons start to produce swamp gas. And the swamp gas, it turns out, goes back to that particular thread of neurons and strengthens the connection. So it's almost like turning a hiking trail into a paved road such that things happen faster, better, if that kind of makes sense. Yeah, yeah, that totally makes sense. So we got really interested in this. So we talked to like a researcher who works in this.

This is what she studies. Her name is Bindu Paul. She did an experiment where she created mice that were incapable of producing hydrogen sulfide. So they had none. And she ran them through a maze. And, you know, when you run a mouse through a maze, basically the first time they run through the maze, they take some time to figure it out. Second time, they get a little better, third time better. And after 10 times, you know, they go straight to the place that they're supposed to go.

You know? The little hole. The little hole. But as she runs these hydrogen sulfide depleted mice, these mice that can't make swamp gas through the maze, she's surprised to find out that every time they run the maze, it's like it's the first time they've ever done it. They don't get any better.

She's looking at these mice and she's like, wow, it's almost like these mice have Alzheimer's. And interestingly, humans who have Alzheimer's produce less hydrogen sulfide than people who don't. So she does another. experiment where she goes and gets some Alzheimer's mice, which you can buy online. You can buy mice with Alzheimer's. Their version of Alzheimer's, so she buys some of these mice.

And she takes these mice and exposes them to hydrogen sulfide gas. She pumps them full of hydrogen sulfide gas. We found that these same Alzheimer's mice, when you inject them with hydrogen sulfide, they are almost as good as the normal mice because, yes, their learning and memory deficits are prevented or even reversed with hydrogen sulfide. Ooh. So hydrogen sulfide gas is essentially reversing and preventing the effects of Alzheimer's in these Alzheimer's mice.

Yeah. Are we now doing it in people rather than just mice? Good question. It's still mouse studies, still a little early to do that. Wait, but then, like, why did you fart on Matt earlier? Oh, well, that's just something we do. I ask for that regardless of what it does to my memory. Everyone warms up for a show differently, okay?

But yeah, you know, not ready for human use yet, but there is this really interesting place where something's going on. I'm talking about Rotorua in New Zealand. So this town naturally has a lot of, like, hot springs, and they just have lots of hydrogen sulfide gas. A lot of gas. Swamp gas everywhere. And when you run the people of this town through finger-tapping tests,

which are like how you can screen for, like, Parkinson's, stuff like that, they do better than the general population. So kind of interesting. Now, that's not to say you have to move to Rotorua. You don't have to move to, you know, the Jersey Turnpike or whatever. I'll take the Alzheimer's please. You can come visit me there anytime. Maybe there's another way.

You can also consume food stuff such as garlic, broccoli, or, you know, Shittake mushroom. I can have these sulfur compounds. So you're saying if you eat more. sulfur in your diet, then your body's able to use those ingredients to make more hydrogen sulfide? Yes. Right now, for me, the safest way to boost your H2S protective way. It's pizza. It's mushroom and garlic pizza. Why not? Why not? Yeah. Incredible. You know, it just, I just think about this a lot. It just boggles my mind that the human body would use a toxic gas in the brain to do something so important as like encoding memory.

It's crazy to me. What is the logic behind that? Right. So to answer this question, we have to go back in evolution, so several eons ago. So at that time, we don't have oxygen. We have hydrogen sulfide instead. So our body still retain the ability to use hydrogen sulfide. Wait, so you're saying like this is like almost like an antique, like ancestral.

process. Yes, it is a very ancestral process and it has been written throughout evolution. Okay, so turns out while Aver was talking to Bindu, I was doing as one does reading about the origins of sulfur and

like Bindu said, if you go back about three billion years ago, you didn't have much oxygen in Earth's atmosphere and instead, and right here, you can Grab your brown paper bag again.

We also had people pull out a little smell strip. Yeah, so what you are smelling is a sulfurous volcanic ash. Oh, what did that one smell like? Very earthy, earthy and smoky. And like there's a sharpness to it. Now, what's going on is you had sulfur coming from the molten core rushing up, exploding out of the earth's crust and into the atmosphere. But more importantly, if you went deep,

Down, down, down. To the ocean floor. You also had sulfur coming up in these deep sea vents. Now, you've probably seen these. These are kind of considered to be the origin of life. What you had is you had tiny little basic simple microbes that were hanging out near these vents. And what they were doing is they were using the sulfur

that was coming out of them as their source of life, of energy, in order to sustain themselves grow. And about 500 million years later, when oxygen does show up and kind of revolutionizes everything, sulfur manages to stick around. But sulfur, because it's so important, it gets incorporated into these complex cells. It becomes a part of, like, amino acids and proteins.

In fact, it is a thing that gives hair, that little curl, like Aver and Mona's beautiful hair. It's also, it is a thing that, like, helps your genes turn on and off. It's a part of a molecule that prevents your cells from just breaking down, decaying too fast, so it kind of prevents you from aging too fast. Scientists have actually found sulfur literally in almost every matter of life here on Earth, which is why.

There are astrophysicists currently using the James Webb Telescope in order to look deep out into space, millions and millions of layers of ways. And they're looking for a faint trace of sulfur, this little signal possibly of life somewhere else out there in universe. And so the next time you find yourself walking around and maybe Central Park if you want to come down to New York City, great city, or you're walking through the Boston Commons and you catch a whiff of just something that's like, you know, rotten eggs. Just take a moment. plant your feet and breathe it in and smile knowing,

that's the smell of life, baby. Okay. Thank you, thank you, thank you so much. Okay, these smells were brought to you today by senior producer Matt Kilty, Dr. Aviramitra, producer, Mona McGalker, with... Yeah, a special shout out. Thank you to our guest, Jeanette Conant. You can check out her book, The Great Secret.

Thank you to the Radio Lab team who helped make this live episode possible. Mona McAulker, Pat Walters, Sarah Sandbach, Natalia Ramirez, Jeremy Bloom, Harry Fortuna, Molly Webster. Did I? I? I guess so. Gabby Santas. Arienne Wack, David Gable. Maya Appleby, Milamid, Jason Saul, fact-checking by Rachel Gross.

Special thanks to Dr. Sarah Seeger, Justin Cox, Imran Umer, Chris Collin, Sophia Colette, Eric of Olfactory Heritage Consulting, and Gus, who developed a lot of the scents that our audiences smelled. person. We should tell people if they like this element show, they should go listen to our element show. Oh yeah, yeah, yeah. That would be so fun. Yeah. If you like this element sulfur, we actually have a whole episode about other elements. Called elements. Okay. Do we do everything? We did everything for this episode, but we do have another Visera show coming up next month is November 5th, New York City. Go to WNYC.org slash events for details and buy some tickets. Thanks for listening. Bye. Hi, I'm Maya, and I'm from London.

And here are the staff credits. Radio Lab is hosted by Lulu Miller and Lativ Nasser. Soren Wheeler is our executive editor. Sarah Sandbach is our executive director. Our managing editor is Pat Walters. Dylan Keith is our director of sound design. Our staff includes Jeremy Bloom, W. Harry Fortuna, David Gable, Maria Paz Gutierrez,

Sindu Naina Sanbandan, Matt Kielte, Mona Maud Gauke, Alex Nissen, Sara Cari, Natalia Ramirez, Joanna Strogatz, Anisa Vizza, Ariane Wack, Molly Webster and Jessica Young. With help from Maya Appleby Malamid, Laura Carpas and Olivia Rose Greco. Our fact checkers are Nora Belblydia, Hillary Elkins, Rachel Gross, Diane Kelly, Emily Krieger, Natalie Middleton and Sophie Semai. Hi, I'm Monica, and I'm calling from Mexico City. Leadership support for Radio Lab Science Programming is provided by the Simon's Foundation and the John Templeton Foundation. Foundational support for Radio Lab was provided by the Alfred P. Sloan Foundation.