CRYSTAL CITY, Mo. -- Chlorine gas poured from a freight car at a chemical plant near St. Louis after a hose ruptured Wednesday, causing a toxic cloud that forced the evacuation of hundreds of residents and left 28 people hospitalized.
The leak happened at around 9:30 a.m. at DPC Enterprises near Crystal City, about 30 miles south of St. Louis. Throughout the morning, yellowish clouds poured from the car but appeared to hang close to the ground near the site. About 80,000 pounds of gas were in the tank when the rupture occurred.
Emergency workers wore protective suits to keep the chlorine from coming in contact with their skin. The leak was stopped shortly after noon. Federal investigators and the Missouri Department of Natural Resources were investigating.
About 50 people, including plant workers and nearby residents, complained of breathing problems, "nothing real serious," Jefferson County Sheriff's Department Capt. Chris Pigg said. All of the 28 who were hospitalized -- plant workers and people living near the plant -- were in fair condition.
Variety of uses for chlorine
Chlorine is a chemical with a variety of manufacturing uses. It is also used to help sterilize drinking water and pool water. In small doses, the gas can cause eye and skin irritation, health experts said. Larger exposures can cause respiratory problems.
"In extreme situations your lungs can fill with water and death can result," said Dr. Becky Tominack of the Missouri Regional Poison Center in St. Louis.
Authorities estimated that 300 to 500 residents of the Blue Fountain mobile home park were evacuated to a school, as were residents of a second mobile home park near the scene. Weather conditions helped -- wind was light, keeping the cloud from spreading too far, and a steady rain helped to knock down the toxic cloud.
A section of Interstate 55 was closed briefly, but U.S. 61 near the scene remained closed by late afternoon Wednesday.
Several calls to the DPC office were met with busy signals. But plant manager Jason Wisdom told the St. Louis Post-Dispatch that officials were uncertain what caused the line to break.
DPC operates chlorine packaging plants throughout the United States, Wisdom said. He said the Jefferson County plant had been operating for about 30 years.
Residents said rescue workers came to their neighborhood with bullhorns telling them to evacuate the area.
"When the firefighters come to your door with gas masks on, it's like World War III," Rosemary Benson said.
Adrian Goodwin, 21, was working at a nearby construction company when he was hit by the greenish-yellow cloud. He told the Post-Dispatch he immediately felt burning in his throat and could not speak. Then, it became hard to breathe.
When Goodwin reached the parking lot of Jefferson Memorial Hospital, he jumped out of the car and fell to the ground, unable to breathe or walk any further. He was later feeling fine and breathing regularly, but said his throat "still felt like it was on fire."
Leo Malone, a chemistry professor at Saint Louis University, said chlorine is a dense gas that "tends to hug the ground" rather than spread over a wide area.
The first sign of exposure to chlorine is irritated eyes, Tominack said.
"If there's no eye-burning, chances are you won't get a sneak attack in your lungs," she said.
For those who are concerned they might have been exposed, Tominack suggested removing all clothing and taking a shower. If eyes seem irritated, she suggested using a wash cloth to wash them out. Anyone with persistent symptoms should go to an emergency room, she said.
The chlorine could kill grass and other nearby plants, but Tominack said cleanup won't be necessary.
"There will be no contamination -- it will dissipate," she said. "Because this is a gas, Mother Nature will clean up."
DPC was the site of another chlorine leak in 1999, when a cylinder of the chemical ruptured after being dropped by a crane operator. More than 100 people were evacuated and more than a dozen were hospitalized.