AIKEN --- The January 2005 Graniteville train wreck could have an upside, according to a study that advises large cities on how to handle the release of chlorine gas.

"Public health agencies and hospitals across the country can learn a lot from this disaster and be better prepared to help in the next emergency," James Gibson, a co-author of the report released last week, said in a statement.

Dr. Gibson is the director of the Bureau of Disease Control at the South Carolina Department of Health and Environmental Control, which, along with the federal Centers for Disease Control, funded the study.

The study says hospitals need to be able to quickly recognize the signs of chlorine exposure, and it recommends that mechanical ventilators "should be an integral component of emergency planning."

Chlorine gas is an irritating, fast-acting and potentially fatal inhalant, and its use in water treatment and industrial manufacturing makes it one of the most used toxic chemicals.

The U.S. Department of Homeland Security has said that an intentional attack on a chlorine storage tank in an urban area is a concern, listing it among its 15 national planning scenarios.

According to the agency, if a chlorine storage tank in a high-density area were attacked, about 100,000 people would be hospitalized and 10,000 would die.

About 2:30 a.m. Jan. 6, 2005, a freight train carrying three chlorine-filled tankers crashed into a parked locomotive in Graniteville, rupturing one tank and releasing about 60 tons of chlorine. The chemical became a cloud of dense gas that stayed close to the ground and spread to the nearby textile mill, where about 180 people were working the night shift.

Nine people died. More than 500 were treated in emergency rooms and 71 were hospitalized at nine hospitals in South Carolina and Georgia.

"It was a tragic disaster that shows us what a significant challenge a large-scale chlorine gas release poses to health care facilities," Dr. David Van Sickle of the University of Wisconsin, the study's lead author, said in a statement.

While small accidental exposures to chlorine gas are common, the Graniteville accident is one of the largest community exposures in recent history. As a result, the CDC and DHEC sought to learn as much as they could about the health effects from the widespread exposure to chlorine gas, the statement said.

According to the study, several of the people hospitalized showed severe lung damage. Some were admitted to intensive care, and about 10 percent required mechanical ventilation. However, most recovered quickly and were discharged in about a week.

Dr. Gibson said DHEC continues to monitor area residents for long-term effects.

Reach Michelle Guffey at (803) 648-1395, ext. 110, or michelle.guffey@augustachronicle.com.