Back in 1994, an ordinary Saturday night at Riverside General Hospital turned into a bizarre medical mystery that baffled health officials and made national headlines.

According to a report published by Discover Magazine in April 1995, at around 8:15 p.m. on February 19, paramedics rushed 31-year-old cervical cancer patient Gloria Ramirez into Trauma Room One.

She was conscious but barely able to speak, hyperventilating, and her blood pressure was rapidly dropping because of an abnormally fast heart rate.

Respiratory therapist Maureen Welch noted that while such symptoms were common among elderly patients, they were unusual in someone as young as Ramirez.

Doctors immediately administered several emergency drugs to stabilise her heart and sedate her, while Welch used an Ambu bag to help her breathe.

When Ramirez failed to respond, the medical team prepared to use electrical shocks to restore her heart rhythm.

After removing her shirt, staff noticed a strange oily sheen on her skin and a distinct fruity, garlic-like odour coming from her mouth.

The situation took an even stranger turn when nurse Susan Kane drew a blood sample. As the syringe filled, Kane noticed an unusual chemical smell. She handed the vial to Welch, who detected an ammonia-like odour before passing it to resident physician Dr Julie Gorchynski.

Gorchynski observed unusual light tan crystals floating in the blood, a finding later confirmed by the attending emergency physician, Dr Humberto Ochoa.

Moments later, medical staff began collapsing.

Kane felt a burning sensation on her face, became lightheaded and lost consciousness.

Gorchynski experienced nausea and dizziness, left the room, then fainted at a nearby desk after suffering irregular breathing. Welch also collapsed and later regained consciousness, unable to control her limbs.

As more personnel reported feeling ill, hospital administrators declared an internal emergency. Dr Ochoa ordered the evacuation of the emergency room, with patients moved to the parking lot.

A small team remained behind in a final attempt to save Ramirez, but despite repeated defibrillation and medication, she was pronounced dead at 8:50 p.m.

Outside, hospital staff were treated in their underwear while their clothing was sealed in plastic bags over fears of chemical contamination.

By the end of the night, 23 of the 37 emergency room workers had developed symptoms. Five were hospitalised, including Dr Gorchynski, who spent two weeks in intensive care suffering from apnea, hepatitis, pancreatitis and severe bone damage to her knees.

Hazmat teams searched the emergency room later that night for hazardous substances, including hydrogen sulfide and phosgene gas, but found no trace of dangerous chemicals. Pathologists conducting Ramirez’s autopsy wore airtight protective suits, yet toxicology tests revealed no obvious poison.

State health officials later concluded that the incident was most likely a case of mass sociogenic illness, commonly known as mass hysteria, triggered by stress and an unusual smell.

The hospital staff strongly rejected the conclusion, arguing that experienced medical professionals do not collectively collapse during a routine emergency response because of stress alone.

Seeking another explanation, researchers at the Lawrence Livermore National Laboratory reopened the case. Led by chemists Brian Andresen and Pat Grant, the team found elevated levels of dimethyl sulfone in Ramirez’s blood, a compound derived from dimethyl sulfoxide (DMSO).

The researchers proposed that Ramirez may have been using a DMSO gel as a home remedy to relieve severe cancer pain, explaining the oily coating on her skin and the garlic-like smell.

According to their hypothesis, oxygen administered by paramedics converted the DMSO into dimethyl sulfone.

The cooler temperature in the emergency room may then have caused the compound to crystallise into the tan particles observed in the blood sample.

They further suggested that electrical shocks or chemical reactions in the bloodstream transformed the compound into dimethyl sulfate, a highly toxic chemical capable of causing paralysis, respiratory failure and organ damage.

Although the Riverside Coroner’s Office accepted the Lawrence Livermore team’s explanation as the most likely cause, the theory remains controversial.

Many organic chemists and toxicologists continue to question whether such a chemical conversion could naturally occur inside the human body, leaving the death of Gloria Ramirez one of modern medicine’s most enduring mysteries.