About 8:15 in the evening on February 19, 1994, paramedics wheeled a young woman into the emergency room of General Hospital in the southern California city of Riverside. They shot through two sets of double glass doors, veered to their left, and parked her in a small curtained space marked trauma room one. The woman, clad in shorts and a T-shirt, was awake, but she responded to questions with only brief and sometimes incoherent utterances. She was taking shallow, rapid breaths. Her heart was beating too rapidly to allow its chambers to fill before they pumped, so her blood pressure was plummeting. The only thing unusual about her was her age, recalls Maureen Welch, a respiratory therapist who was assisting in the trauma room that night. Most patients who show up in an emergency room with such symptoms are elderly people, Welch says. This woman, the paramedics reported, was 31 years old and had cervical cancer. Her name was Gloria Ramirez.

The medical staff hovering over Ramirez injected her with a host of fast-acting drugs that were part of the standard protocol for her condition: Valium, Versed, and Ativan to sedate her, and agents such as lidocaine and Bretylium to quell her aberrant heartbeat. Welch, meanwhile, forced air into Ramirez’s lungs with an Ambu-bag, a football-size rubber bladder connected to a plastic mask that’s placed over the patient’s nose and mouth, serving as a sanitary alternative to mouth-to-mouth resuscitation. When it became clear that Ramirez was responding poorly to treatment, the staff tried to defibrillate her heart with electricity. They stripped off her shirt and pressed padded electrodes against her chest; at that point several people saw an oily sheen covering Ramirez’s body, and some noticed a fruity, garlicky odor that they thought was coming from her mouth.

To obtain blood for analysis, a registered nurse named Susan Kane swabbed Ramirez’s right arm with rubbing alcohol, inserted a catheter, and attached a syringe. And that’s when the frenetic yet orderly routine of the emergency room began to break down. As the syringe filled, Kane noticed a chemical smell to the blood. Kane handed the syringe to Welch and leaned closer to the dying woman to try to trace the odor’s source. Welch sniffed the syringe and smelled something, too: I thought it would smell like chemotherapy, the way the blood smells putrid when people are taking some of those drugs. Instead, Welch says, it smelled like ammonia. She passed the syringe to Julie Gorchynski, a medical resident who noticed unusual manila-colored particles floating in the blood — an observation echoed by Humberto Ochoa, the doctor in charge of the emergency room, who was helping treat Ramirez.

Kane turned toward the door of the trauma room and swayed. Catch her! someone shouted. Ochoa lunged for Kane, caught her, and gently guided her limp body to the floor. Kane said that her face was burning, and she was put on a gurney and taken from trauma one. Gorchynski too began feeling queasy. Complaining that she was light-headed, she left the trauma room and sat at a nurse’s desk. A staff member asked Gorchynski if she was okay, but before she could respond she slumped to the floor. She was now the second member of the Riverside emergency room staff being wheeled away from the trauma room on a gurney. Gorchynski shook intermittently; over and over again she would stop breathing for several seconds, take a few breaths, then stop breathing again — a condition known as apnea. Meanwhile, back in trauma one, Welch became the third to succumb. I remember hearing someone scream, Welch says. Then when I woke up, I couldn’t control the movements of my limbs.

That surreal night would throw Riverside General Hospital into newspapers and tv news broadcasts for weeks, as the frightening possibility of a human body releasing toxic fumes captured the public’s imagination. It also triggered one of the most extensive investigations in forensic history — medical detectives from ten local, state, and federal outfits examined dozens of potential culprits, from poisonous sewer gas to mass hysteria. So far, all the suspects have beaten the rap, except for one extraordinary hypothesis: a team of researchers think that a chain of chemical reactions may essentially have turned Gloria Ramirez’s body into a canister of nerve gas.

After Welch collapsed, several other staff members began to say they felt ill, and hospital administrators declared an internal emergency. Ochoa ordered the staff to evacuate all emergency room patients to the parking lot outside the hospital. A skeleton crew stayed behind to help him in a desperate struggle to save Ramirez’s life. Her blood pressure continued to drop, and her pulse was growing fainter. Ochoa and three others repeatedly administered electric shocks and drugs, but their efforts to stabilize Ramirez failed. At 8:50 Ochoa pronounced her dead. Two staff members moved the body to an isolation anteroom adjacent to trauma one.

Outside, in the parking lot, hospital staff were treating patients and ill colleagues under the dull orange glow of sulfur lamps. Because of concern that the stricken staff had been felled by a noxious chemical, they were stripped down to their underwear, and their clothes were bundled into plastic bags. Gorchynski continued to experience tremors and apnea. Kane flailed her arms and kicked, and her face still burned. Meanwhile, Sally Balderas, a vocational nurse who had gone back inside to help take Ramirez’s body into the isolation room, began retching and felt a burning sensation on her skin. Soon she was in such bad shape that she too was laid out on a gurney.

In all, 23 of the 37 emergency room staff members experienced at least one symptom. Five were hospitalized for the rest of the night. Balderas endured bouts of apnea during a ten-day hospitalization. Gorchynski, the most severely ill, spent two weeks in intensive care, where in addition to apnea she suffered from hepatitis, pancreatitis, and avascular necrosis, a condition in which bone tissue is starved of blood and begins to die. In her case the avascular necrosis attacked her knees, restricting her to crutches for months. It takes a really damn potent toxin to do all that, says Sheldon Wagner, a clinical toxicologist at Oregon State University.

First on the scene, arriving at the hospital at around 11 p.m., was a Riverside County hazardous materials team. The hazmat team was after a smoking gun — some volatile toxicant that might yet be lurking in the air of the emergency room. They searched for any of a host of noxious chemicals, including hydrogen sulfide (also known as sewer gas), an insidious poison that smells like rotten eggs and at high concentrations can kill a person after one or two whiffs, and phosgene, a gas with a dual identity — on the one hand, a law-abiding ingredient used in the preparation of many organic chemicals, and on the other a terrible weapon for chemical warfare that tears open capillaries in the lungs, drowning its victims in blood. To the relief of hospital administrators, the hazmat crew detected none of these chemicals in the emergency room.

The hazmat team’s lack of suspects was not a relief, however, to the Riverside Coroner’s Office, whose pathologists were now left with the unnerving task of performing an autopsy on Ramirez without a clue as to what the body was harboring — perhaps a fugitive pathogen, a toxic chemical, or nothing at all. Taking no chances, they put on airtight moon suits and disappeared into a sealed examining chamber to work on the body. They emerged 90 minutes later with samples of blood and tissue along with air from the body bag and aluminum crate holding the body.

The coroner’s office has remained tight-lipped about the analysis it conducted in the days that followed. One thing, however, is certain: several days after the autopsy, the Riverside coroner had still found nothing remarkable and had begun to solicit help.

One consulting group was an obscure outfit called the Forensic Science Center, at the Lawrence Livermore National Laboratory. Livermore, situated about 60 miles east of San Francisco, is rooted in the nuclear arms buildup that started shortly after World War II. But in the past decade, as the production of nuclear weapons has tapered off, Livermore and its fellow labs have attempted to find an identity better suited to a post- cold war world. That goal fostered the creation, in 1990, of the forensic center, a clearinghouse that would allow state and federal law enforcement forensic teams to enlist high-tech aid from scientists at Livermore and other Department of Energy labs.

The forensic center took up the Ramirez case in early March, when a Sacramento criminologist put the Riverside Coroner’s Office in touch with the center’s deputy director, Pat Grant. On March 25, after some preliminary discussions, the office officially requested Livermore’s help and shipped autopsy samples, on dry ice, to the lab.

We had a meeting on the very last day of the month to determine our exact game plan, says Brian Andresen, the center’s director. The plan they developed was straightforward: analyze the compounds, both organic and inorganic, in the blood, bile, and tissues from Ramirez’s organs, including her heart, liver, lungs, brain, and kidneys. The team would also check for any gases that may have vented off the samples into the headspace, the pocket of air separating the samples from the tops of their containers.

Andresen suspected that the headspace would be a likely retreat for a noxious gas — particularly in the container holding the bile, a yellowish secretion of the liver, where poisons often concentrate. But when he warmed the bile to body temperature to pull out any gases still lurking in it, all he found was nitrogen, oxygen, carbon dioxide, and argon — normal constituents of air. I was hoping to see a chemical, some small molecule that’s going to knock everybody down, but nothing was showing up there, he says.

Next Andresen analyzed the samples using a high-powered tool known as a computer-guided combined gas chromatograph-mass spectrometer. The procedure was as follows: First Andresen inserted a drop of a prepared sample into the chromatograph. The drop, containing hundreds of chemicals, was vaporized and shunted into a chromatography column, where it was slowly heated to 570 degrees. As the vapors grew warmer, chemicals began to migrate along the column, sorting out along the way according to their electric charge and vapor pressure. Andresen measured their concentrations and then piped the vapors into the mass spectrometer chamber, which fires electrons at the chemicals. The electrons shatter the molecules into all types of pieces, says Andresen. The shattering pattern, unique to every substance, is called a mass spectrum.

By studying the mass spectra, Andresen divined the identity of a number of compounds that had been circulating in Ramirez’s system just before her death; among them were the drugs lidocaine, Tylenol, codeine, and Tigan, an antinausea medication. Andresen also found a lot of hydrocarbons, chemicals that had leached into the samples from their sterile plastic containers. Medical personnel think of sterile as being without bugs, not without chemicals, Andresen says. So the products they use are superclean and sterilized but covered in chemicals. A trained forensic eye can quickly dismiss such misleading signals.

Ignoring the red herrings, Andresen found a few interesting anomalies. One was an unidentified amine, a derivative of ammonia, that may have contributed to the ammonia-like smell noted in the emergency room. The investigation by the National Institute for Occupational Safety and Health had also found this amine and had suggested that it was a possible culprit, despite its minuscule levels in the autopsy samples. Andresen’s team had a more likely explanation for the amine, though: they said it formed as Ramirez’s body broke down the antinausea drug Tigan.

A second peculiar find was nicotinamide — a compound, like phosgene, with a dual personality. It’s a B vitamin crucial to human health, but it’s also mixed into illegal drugs like methamphetamines. Since nicotinamide is relatively inexpensive and can cause euphoria, dealers can extend their expensive drugs with it and make a larger profit. It’s an unusual compound for someone to be taking if they’re very, very sick, says Andresen.

A third odd chemical signal defied being pigeonholed as either trivial or important: dimethyl sulfone. Dimethyl sulfone is a molecule composed of one sulfur atom, two carbons, six hydrogens, and two oxygens. It is manufactured as an industrial solvent, but it is also sometimes produced naturally in our bodies from amino acids that contain sulfur. Broken down by the liver, dimethyl sulfone has a half-life in the body of less than three days, so healthy people never have measurable amounts in their system. But in Ramirez’s blood and tissues there was a hefty concentration of tens of micrograms per milliliter, about three times higher than the codeine in the samples. At this point in the mystery, the only unusual thing we’re seeing is dimethyl sulfone, says Andresen.

But dimethyl sulfone itself couldn’t knock out an emergency room, so when Andresen flew to Riverside on April 12 to brief the coroner, his conclusion was that he had found nothing that looked like a poison. Andresen recalls some anxious questioning by the coroner’s office in hopes of finding a smoking gun, but he insisted that it appeared Ramirez had simply taken a lot of codeine and Tylenol, which in large, sustained doses can damage the liver. He also highlighted the findings that had intrigued him: the amine that might have caused the ammonia-like odor, the nicotinamide, and the dimethyl sulfone. There clearly was something unusual going on, but nothing that could have resulted in Ramirez’s death or the emergency room symptoms, Andresen says. He was discouraged. I remember thinking, ‘How could I spend this much time and not find anything?’

The riverside coroner’s office felt it had reached the end of the road, too. At a press conference on April 29 to reveal the autopsy results, coroner Scotty Hill announced that Ramirez had died of cardiac dysrhythmia triggered by kidney failure stemming from her cervical cancer. The investigation into her death, Hill said, was finished. As for the illness in the hospital workers and how that might be linked to Ramirez, Hill concluded that exhaustive toxicological studies have not identified any external toxic substances that would have contributed to her death.

Although the books on Ramirez’s death were now officially closed, there was no explanation for the outbreak of illness among the hospital staff. The county health department called in California’s Department of Health and Human Services, which put two of its top scientists on the case, Doctors Ana Maria Osorio and Kirsten Waller. They interviewed 34 hospital staff who had been working in the emergency room on February 19. Using a standardized questionnaire, Osorio and Waller found that the people who had developed severe symptoms such as loss of consciousness, shortness of breath, and muscle spasms tended to have certain things in common. Perhaps unsurprisingly, people who had worked within two feet of Ramirez and had handled her intravenous lines had been at high risk. But other factors that correlated with severe symptoms didn’t seem to match a scenario in which fumes had been released: the survey found that those afflicted tended to be women rather than men, as well as people who had skipped dinner that evening rather than those who had a full stomach.

Those findings, coupled with the autopsy results, the hazmat analysis, and unremarkable blood test results from the stricken hospital staff, led to an official report that the health department released on September 2. The conclusion: The hospital staff most likely experienced an outbreak of mass sociogenic illness, perhaps triggered by an odor. In other words, they’d been felled by stress and anxiety. In support of this mass hysteria theory, Osorio and Waller cited the lack of evidence for a poison and the fact that women were more likely to suffer severe symptoms, both hallmark signs of mass hysteria. In addition, they pointed out, neither paramedic who had treated Ramirez in the ambulance became ill — despite the close quarters and their having touched her skin and some of her blood after starting an intravenous line. However, Osorio and Waller did not rule out the possibility that some substance poisoned emergency room staff who had worked directly over Ramirez.

The health department’s report triggered another flurry of news reports; these featured Gorchynski and her lawyer, physician Russell Kussman, who denounced the mass hysteria conclusion. By this time Gorchynski had filed a lawsuit against Riverside General Hospital, the coroner’s office, and several others, seeking $6 million in damages. A report suggesting Gorchynski experienced psychosomatic symptoms would certainly not play well for her in court. The report may be based on politics or ignorance, but it’s not based on science, Kussman told the New York Times. These are all professional emergency room workers. They don’t become hysterical because of a heart attack.

The state report also angered some of the other emergency room staff, including Welch. She was convinced that neither she nor anyone else that night had been party to mass hysteria. She wanted someone to look at the case more closely, and in her opinion Livermore was the only laboratory involved without a vested interest. Welch called Andresen at Livermore and implored him to take another look. To help lure him back to the case, she sent him a copy of a scrapbook of material she had accumulated, including news stories, the Riverside coroner’s report, legal briefs, and toxicology reports.

Andresen asked Grant, his deputy director, to sift through the file. To refresh Grant’s memory of the case, he also showed him his results, including the puzzling compounds he had identified. Andresen laid out a paper with the gas chromatography-mass spectrometry results, a graph with spikes similar to earthquake readings on a seismograph, and pointed at the dimethyl sulfone peak.

Grant was a bit hesitant. I’m a nuclear chemist, and my organic chemistry knowledge truthfully is minuscule, he says. Grant mistook dimethyl sulfone for dimethyl sulfoxide, or DMSO — the only difference between the two chemicals is that DMSO has one oxygen atom, not two. Grant was more familiar with dmso because, he says, I’d used dmso in a former life as an athlete. DMSO is sold in a gel form at hardware stores as a heavy-duty degreaser, and it has long been a folk remedy among athletes for achy muscles and joints. Andresen corrected him, saying the spike was dimethyl sulfone. Grant didn’t get to Welch’s file until a few days later when he was on a flight to a business meeting in Washington, D.C. There were a lot of things we hadn’t seen before, he says. One thing that particularly struck him was a speculation in the autopsy report about the source of the garlicky odor of Ramirez’s body and its oily sheen: DMSO.

DMSO has a checkered past. During the mid-1960s a flurry of research showed it had remarkable healing powers, easing intractable pain and reducing anxiety. But the rise of this potential wonder drug was stopped suddenly when animal tests showed that prolonged exposure to DMSO altered the lens of the eye. Fearing that a DMSO drug might ruin people’s eyesight, the Food and Drug Administration ordered companies to cease clinical trials of the drug in 1965. The FDA later relaxed that policy and in 1978 approved a 50 percent solution of DMSO as a treatment for interstitial cystitis, a condition marked by painful urinary tract lesions that occurs predominantly in women.

Meanwhile, over the past 30 years, DMSO gained an underground following as a home remedy. Not only did Grant use it, but Andresen as well remembers the DMSO rage from his days during the 1970s as a pharmacology professor at Ohio State University. It seemed that everybody in the athletic department was using dmso on injuries, he recalls.

Nor has its use been limited to athletes. People use it for a variety of ailments, from arthritis to muscular strains, says George Rutherford, California’s state epidemiologist. But given its potential side effects, it’s a dangerous remedy because in its readily available hardware- store grease-cutting form, it’s 99 percent pure. Alarmed by the growing cult of DMSO users, the FDA issued a warning to physicians in 1980: Counsel patients against purchasing dmso of unknown quality and medicating themselves.

Even if Ramirez had applied DMSO to her body to ease her pain, however, and even if it had combined with oxygen to form the dimethyl sulfone Andresen had found, that still didn’t explain the outbreak among the hospital staff. Grant decided to find out more about DMSO and dimethyl sulfone, so when he got back to Livermore he looked up the two compounds in the Merck Index, a chemist’s bible that describes the characteristics of more than 10,000 chemicals, drugs, and biological substances. Since DMSO can react with oxygen and form dimethyl sulfone, Grant began to wonder what other compounds might be formed when oxygen is added to the chemical. On the same page of the index he had been reading, he found the answer: dimethyl sulfate. It was one of those deals that was pretty fortuitous, Grant says.

In chemistry little changes can sometimes lead to big results. Add one oxygen atom to DMSO and you get dimethyl sulfone — you change one solvent to another. But now add two oxygen atoms to dimethyl sulfone — which in chemical notation is written (CH3)2SO2 — and you get dimethyl sulfate, (CH3)2SO4, a truly nasty chemical. Vapors of dimethyl sulfate, the index explained, kill cells in exposed tissues, such as the eyes, mouth, and lungs. When absorbed into the body, dimethyl sulfate causes convulsions, delirium, paralysis, coma, and delayed damage to the kidneys, liver, and heart. In severe cases, the vapors kill. Like many other chemicals, dimethyl sulfate has a good side and a bad side. Industries use dimethyl sulfate to tack methyl groups onto organic chemicals. But the index also said dimethyl sulfate is a war gas.

Here finally was a chemical that could cause some real damage. Realizing dimethyl sulfate was their best lead yet, Richard Whipple and Jeffrey Haas, chemists at the forensic center, searched among the thousands of papers that have been written about these compounds. One reference was particularly enlightening, if grisly — a classified Department of Defense document, issued in 1987, called the Reference Book on Chemical Warfare Information. It reported that a ten-minute exposure to half a gram of dimethyl sulfate dispersed in a cubic meter of air can kill a person. (Although dimethyl sulfate has been tested as a nerve gas, it has apparently never been manufactured for use in war.)

The Livermore team was able to cull details about the symptoms of dimethyl sulfate exposure from the reference book, as well as from a safety sheet that accompanies any dimethyl sulfate purchased by industry. (A liter of liquid dimethyl sulfate sells for around $32.) The match between the symptoms experienced by the hospital staff and the symptoms of dimethyl sulfate exposure was uncanny. Of the 20 types of symptoms reported by the staff, from the fainting to the convulsions to Gorchynski’s hepatitis, only one — nausea and vomiting — is not a symptom of dimethyl sulfate exposure. When there was such a nice match on the symptoms — that was the first indication that we might really have had something, Grant says.

Still, the forensic team realized they needed to answer some tough questions — and do an important experiment — before they would feel comfortable explaining their theory to the Riverside coroner. And despite their desire to press forward, they had to put the Ramirez case on the back burner for the rest of September. The Livermore scientists had been working on the case for free as a public service, after hours and on the weekends. Now they were under the gun to finish a technical report to the organization paying their bills — the U.S. Department of Energy, Livermore’s parent agency — by September 30.

In early October, when the Livermore scientists took up the Ramirez case again, they first had to decide whether her body could have generated the dimethyl sulfate. That Andresen had found evidence of dimethyl sulfone in Ramirez’s blood and organs pointed to her having first been exposed to DMSO. Other precursors of dimethyl sulfate, like sulfur-bearing amino acids, probably couldn’t produce enough of the chemical to wreak so much havoc.

The researchers could think of two scenarios that would explain how Ramirez had been exposed to DMSO. In one, Ramirez spread a cream on her skin that contained phencyclidine (better known as PCP, or angel dust) dissolved in a DMSO carrier base (a common way to take the drug). According to an August report on the Riverside incident by Tam Smalstig, an industrial hygienist with California’s Department of Industrial Relations, the Riverside Coroner’s Office had told the department, without elaborating, that Ramirez’s body had indications consistent with phencyclidine use. This scenario would explain the presence of the nicotinamide that Andresen had found in Ramirez’s blood and tissues — it had been mixed in with the PCP to extend it. But if Ramirez had taken PCP, someone should have found some traces of the drug itself. No one had, and so the Livermore team decided that this scenario was impossible.

Rather, the Livermore team thought the more likely event was that Ramirez had rubbed DMSO on herself to relieve the pain from her cancer. That would account for the oily sheen and garlicky odor observed by the staff. Ramirez’s family has since denied she was using DMSO or PCP before her death, but if she did use a DMSO gel for her pain, it would have been far from unusual — it’s been estimated that two-thirds of cancer patients use some kind of unprescribed home remedy for their disease.

When Ramirez collapsed (presumably from cancer-related kidney failure) and was put in an ambulance, the paramedics put an oxygen mask on her face. Oxygen molecules flooded her bloodstream, combining with the DMSO in her system, the researchers hypothesized, to form high levels of dimethyl sulfone. The higher the concentrations of the ingredients required, the more efficiently chemical reactions will run; thus, with so much oxygen, no DMSO was left untransformed.

Now the Livermore team needed to figure out the next step: how the relatively harmless dimethyl sulfone could have been converted to the extraordinarily harmful dimethyl sulfate. This is where we were afraid we might find a showstopper that would kill the theory, says Grant.

They conducted an experiment to see how much dimethyl sulfone could accumulate in the blood at normal body temperature. They dissolved the compound in a transparent liquid called Ringer’s solution, which is basically all the ingredients of blood minus red blood cells. We found we could load it up in the Ringer’s solution to an appreciable extent without any sweat, says Grant. (The autopsy, the researchers note, had found that Ramirez had a urinary tract blockage. That could have aggravated the buildup of dimethyl sulfone by preventing it from being flushed out of her system.)

When they cooled a vial of this Ringer’s solution crammed with dimethyl sulfone to room temperature (about 70 degrees), they were greeted by a good sign. The solution became supersaturated, and dimethyl sulfone began to form beautiful white crystals, says Whipple, who did the experiment with Grant. In real blood those crystals might have appeared manila-colored. Thus this process could have produced the crystals that had been observed in the syringe in the hospital, particularly since emergency rooms tend to be cooler than most rooms — about 66 degrees.

So far, so good. But how did the dimethyl sulfone convert to the nerve gas dimethyl sulfate? The Livermore chemists envision a reaction — which hasn’t yet been observed — in which some of the molecules of dimethyl sulfone in Ramirez’s blood broke apart. What had been (CH3)2SO2 became CH3, CH3, and SO2. Sulfates (SO4) are common in the body, so the two CH3 molecules may have linked up with them to form (CH3)2SO4 — dimethyl sulfate. But in her warm blood, the dimethyl sulfate was unstable and quickly fell apart into its hydrocarbon and sulfate components. There was not yet a sufficient amount of nerve gas to harm the paramedics.

When Susan Kane drew blood at the hospital, however, the cool temperature had slowed the breakdown of the dimethyl sulfate. Appreciable amounts of it built up in the syringe, and some of it vaporized out of the blood. This was the gas that poisoned the emergency room staff. Dimethyl sulfate doesn’t vaporize easily — the Merck Index lists its boiling point as 370 degrees. Nevertheless, according to Grant and other chemists, some fraction will still vaporize at room temperature. The crystals of dimethyl sulfone turned into dimethyl sulfate as well and vanished from sight. In the end, all of the dimethyl sulfate either vaporized or broke back down in the blood into its constituents. And thus the macabre chemistry of that night hid most of its traces from investigators.

It’s a really clever piece of detective work, says Oregon State toxicologist Frank Dost. It would seem to me that it would take a hell of a lot of DMSO, but in that stage of fighting for her life, Ramirez may have really overloaded on it, he says. The Riverside Coroner’s Office apparently agrees — it released the Livermore report last November, hailing its conclusion as the probable cause of the hospital workers’ symptoms.

But the theory has provoked a backlash from other scientists. Several organic chemists have scoffed at the step-by-step change of DMSO into airborne dimethyl sulfate. I’m pretty skeptical, says Hans Reich, an organic chemist at the University of Wisconsin at Madison. Reich doubts that dimethyl sulfone would split apart in the human body’s relatively cool environment. I have used it as a solvent up to at least 300 degrees, he says. Other scientists don’t see a match between the symptoms of the hospital staff and some of the symptoms of industrial workers who have been accidentally exposed to dimethyl sulfate. The stuff is like tear gas, says Jack de la Torre, a physiologist and professor of neurosurgery at the University of New Mexico. When you’re exposed to dimethyl sulfate vapors, the first thing that happens is it makes you start to cry. None of the hospital staff reported tearing or other eye irritation. Furthermore, many other known effects of dimethyl sulfate usually take several hours to hit, and yet the fainting spells and other symptoms at the hospital began to occur minutes after the supposed exposure.

One of the harshest critics of the Livermore theory is a scientist who did much of the clinical research on DMSO in the early 1960s. Stanley Jacob, a physician and medical researcher at the Oregon Health Sciences University in Portland, doubts that significant quantities of the suspect chemicals could have been produced from dmso. In fact, Jacob says, the Livermore scientists should never have allowed the Riverside coroner to release their report. It’s like that silliness with cold fusion, except this has the potential to hurt people, he says. His office has received dozens of calls from worried women being treated with DMSO for interstitial cystitis. I just tell them the dimethyl sulfate theory is a chemical impossibility, says Jacob.

But other scientists come to Livermore’s defense. Marc Micozzi, director of the National Museum of Health and Medicine in Washington, D.C., is one. Micozzi is a forensic pathologist who has helped investigate dozens of unusual deaths. He points out that forensic investigations often fail to find the actual smoking gun, but they can still come to valid conclusions. No one clue gives a perfect fit to explain a death, but when all the clues are added up, you get a pattern. Sometimes it’s a pattern that we’ve never seen before, he says, such as the Riverside case. But even though there’s no way to prove Livermore’s scenario, I think they gave us a report that’s quite interesting and analytical, he says.

Andresen thinks some of the backlash was avoidable. We just wanted the coroner’s office’s opinion, and they took it and said, ‘This is the answer.’ It caught us way off guard. We’ve never said this is what happened, just that people should look into it. And people still go nuts.

Nevertheless, he thinks the hypothesis is a good one. I’ve gotten messages on my answering machine from chemists who say it’s an impossible conclusion, says Andresen. But most hadn’t even read our report, and some of them change their minds after I explain our hypothesis. It is true, he notes, that no one has done experiments to show that dimethyl sulfate is produced when dimethyl sulfone breaks apart and recombines with the body’s sulfates. Yet chemists have on several occasions discovered that seemingly impossible reactions turn out to be quite possible.

Andresen’s team is going to conduct more experiments and check Ramirez’s blood again; soon they hope to turn their preliminary report into a paper they will submit to a refereed forensic journal. Then, thanks to the publicity of the Riverside case, they’ll have no problem shifting from one eldritch tale to another. They’re swamped with calls and letters urging them to get to the bottom of a host of mysteries, from Gulf War syndrome — the symptoms suffered by some U.S. soldiers who fought in the Persian Gulf — to sudden infant death syndrome. People are frustrated and want us to look at these cases from a chemistry point of view, says Andresen.

Fourteen months after the incident, the Riverside case’s legacy remains peculiar and shadowy. If Andresen’s team is right, one has to wonder whether the outbreak was unique. For now, researchers can’t find a similar poisoning in the medical annals, nor can they say whether hospitals should fret about future cases. The Livermore scientists do offer a cautionary note in their report, which recommends that hospitals be made aware of the possible consequences of such a chemical reaction occurring in their emergency rooms. Other scientists are more convinced that action is necessary. This is likely to occur again — DMSO is not uncommon, asserts Barry Taylor, a microbiologist at Loma Linda University School of Medicine who has followed the case closely.

In the end, the Riverside case leaves us with a warning and a puzzle. The warning is that the human body can be a place where bizarre — and potentially deadly — chemistry can occur. The puzzle is that if the Livermore investigators are wrong, then what did happen in the Riverside emergency room on February 19, 1994?