Scientists at the Lawrence Livermore National Laboratory believe a home remedy may have generated fumes that overcame several emergency room workers at a California hospital last February.
The researchers said the substance, used by some people to relieve muscle soreness, may have been involved in a chemical reaction that produced a gas used as a chemical warfare agent. The gas-DMSO 4, or dimethyl sulfate-was produced by transformations of other substances in the body of a patient dying of cancer at Riverside (Calif.) General Hospital.
The scientists, who studied blood samples from patient Gloria Ramirez, found dimethyl sulfone, or DMSO 2, along with large amounts of painkillers, said Craig Savoye, public information officer for the Livermore, Calif.-based laboratory.
"It seems pretty apparent that the DMSO 2 came from DMSO, or dimethyl sulfide, which is a home remedy. People rub it on their skin and it can go right to a joint. It helps with sore muscles" and is readily transformed in the body into DMSO 2, he said.
DMSO, which is available at veterinary stores, is not approved for human use, he said.
Ms. Ramirez, who was suffering from advanced stages of cancer, had been vomiting for two days and was severely dehydrated. She was given oxygen as she was transported to the hospital. The scientists believe that, "combined with her particular pathology, the oxygen oxidized the DMSO 2" and transformed it into the chemical warfare agent DMSO 4, Mr. Savoye said.
When emergency room workers drew her blood, "they were getting a whiff of a chemical warfare agent," he said.
However, dimethyl sulfate dissipates rapidly, so the hazardous-materials crew that initially investigated the incident couldn't spot the source of the fumes that felled the workers, he said.
"We have to conclude (the report) best represents the most plausible solution to the events that occurred," Dan Cupido, chief deputy coroner of Riverside County, told MODERN HEALTHCARE.
The Livermore scientists are not "automatically indicting DMSO" but are hoping health officials will look into its use, Mr. Savoye said.
The emergency room incident had baffled experts. County and local officials said they couldn't find any leaks or problems at the hospital, and the state Department of Health concluded that shared stress among the workers may have caused a psychosomatic illness (Sept. 12, p. 42).
Meanwhile, Russell Kussman, the attorney for Julie Gorchynski, M.D., the emergency room physician most seriously injured by the fumes, has filed a suit in Riverside County Superior Court against the hospital and county and state officials. The $6 million suit charges negligence in investigating the incident (Aug. 22, p. 16).
The Livermore report "doesn't really change our allegations," Mr. Kussman said.