The mysterious fumes that killed one person and sickened nine others inside a McDonald's restroom this week may have brought the most unwanted publicity to the city of Pooler, Ga., since Gen. William Tecumseh Sherman set up Union headquarters there before negotiating the peaceful surrender of Savannah in December 1864.
Local fire officials remained stumped Friday about what toxic chemical or chemical mixture knocked two women unconscious Wednesday at the fast-food restaurant in their east Georgia city of about 19,000. One of the women, Anne Felton, 80, of Ponte Vedra, Fla., died after going into cardiac arrest. Firefighters administered oxygen to Carol Barry, 56, of Jacksonville, Fla., before she was admitted to a Savannah hospital, Pooler Fire Chief G. Wade Simmons said.
"Every one of the 10 people that had some sort of symptoms ... had been or were in that restroom," Simmons said.
No one anywhere else in the restaurant was affected.
He was hoping that results of an autopsy conducted at Georgia's state crime lab in Savannah "will lead us in some direction."
Among other confounding aspects of the case, he said, was how quickly the gas disappeared. "It was there, and then it was gone in the next hour to hour and a half we were doing things at the scene," he said.
By the time a Savannah hazardous materials analyzed air samples from the restroom, they found nothing detectable.
That left law enforcement officials and toxicologists to speculate about what the victims might have inhaled, and how it ended up in the women's room. "We've heard everything from terrorist attacks to carbon monoxide to sewer gas to God knows else," Simmons said.
Much of the speculation centered on the possibility that the women were sickened by a noxious combination of cleaning chemicals. Labels on toilet bowl cleaners, drain openers, window and glass sprays and scouring powders usually caution against using more than one product at a time.
Simmons said that based on employees' routines at the Pooler McDonald's, workers would have cleaned the women's room early in the day, before serving up Egg McMuffins to the morning breakfast crowd. But the initial report of someone choking didn't get called in until just before noon Wednesday, further deepening the mystery of why people suddenly became ill so much later. None of the products on the cleaning cart had spilled, he said, and the cart wasn't even near the bathroom when patrons began developing symptoms.
"Cleaning chemicals are common culprits in bathrooms," said Dr. Kelly Johnson-Arbor, a medical toxicology specialist at Hartford Hospital in Connecticut. "Perhaps the people in the bathroom mixed together bleach and ammonia," which would produce chloramine gas, an irritant. "It doesn't usually cause people to die, but if it's in a high enough concentration and/or the person had underlying cardiopulmonary disease (such as asthma), it could certainly be potentially fatal."
Dr. Marcel J. Casavant, chief of pharmacology/toxicology at Nationwide Children's Hospital in Columbus, said he thought the most likely culprit was hydrogen sulfide, or "sewer gas," which blocks the body's ability to use oxygen. It's called a "rapid-knockdown" gas, he said.
"If the concentration is high enough, just a few breaths could be lethal," he said. "If the restroom has a floor drain connecting to the sewer, and the floor drain has a U-shaped pipe which generally stays full of water, thus keeping the sewer gas out of the restroom, but the water in the U dried up, then gas could freely enter the restroom. "
Although hydrogen sulfide frequently smells like rotten eggs, the gas can knock out the body's smell receptors, "and the smell goes away, so people don't realize they're still in a poisoned atmosphere," Casavant said. "Victims have plenty of oxygen in their blood, but because their cells can't use the oxygen, they gasp, choke, and struggle for air."
Hydrogen sulfide gas is among agents used in so-called chemical suicides, in which people deliberately mix particular household chemicals in an enclosed space like a car to end their lives. Law enforcement officials have seen a growing number of these cases in this country, which followed a spate of cases in Japan in 2008.
Both Johnson-Arbor and Casavant said that another possibility was carbon monoxide, a colorless, odorless gas that could have backed up from a blocked chimney flue, a leak in a ventilation pipe "or someone using gasoline-, propane- or kerosene-powered equipment or generators indoors," Johnson-Arbor said.
Casavant also floated the possibility of a deliberate act. "In this day and age, first responders should also think about the possibility of terrorism and the intentional release of a poison into that atmosphere," he said. "The sarin used in the Tokyo subways in March 1995 caused some people to lose consciousness, and left many people struggling to breathe."
But Simmons said the terrorist scenario was unlikely because people only became sick if they breathed the air in the women's restroom.
Pooler firefighters who arrived at the McDonald's soon learned that people who had tried to help Felton and Barry began falling ill themselves. One of the firefighters treating the women soon began feeling woozy, "like the walls were starting to move in and out on him. He started noticing respiratory problems," Simmons said.
Firefighters then donned special air filtering masks to protect themselves. Three of them were among the 10 people taken to a Savannah hospital for evaluation, although after being checked, all three were back at work Wednesday evening.
But one of the firefighters continued to have some residual effects from the episode. He reported still having a sore throat and irritation in his chest and visited his doctor today as a precaution, Simmons said.
Robert Vazzi, area director of the Savannah, Ga., office of the federal Occupational Safety and Health Administration, said Friday that his office had begun an investigation, which he expected could last a while. OSHA was called into the case to investigate the restaurant workers' potential exposure to the chemicals and to investigate "any safety violations that might have occurred that might have contributed to the accident."
"Hopefully, we'll be coming up with something," Vazzi said. "We may not be able to find anything."