WARRENVILLE — Researchers studying the health effects from a devastating South Carolina train wreck and chlorine gas release are seeking more participants.

At a Midland Valley Area Chamber of Commerce luncheon last week, Dr. Erik Svendsen said he would like several hundred people who used to work for Avondale Mills to participate in his Graniteville Recovery and Chlorine Epidemiology Study, the Aiken Standard reports.

On Jan. 6, 2005, a Norfolk Southern train car carrying chlorine derailed and ruptured, releasing a cloud of the poisonous gas over Graniteville and the Avondale Mills textile plant. Nine people died, and thousands were evacuated. Scores of others have needed hospitalization or treatment.

The gas corroded machinery at Avondale Mills, causing damage from which the Georgia-based company said it could never recover, despite spending more than $140 million on cleaning, repairs and damage mitigation. In 2008, Avondale Mills reached an undisclosed settlement with Norfolk Southern after seeking $420 million in damages in a lawsuit.

Svendsen’s study is funded by a $3 million grant from the National Institute of Environmental Health Sciences. Participants receive pulmonary diagnostic tests at no cost.

According to Svendsen, preliminary testing has shown that those closest to the incident experienced aging of their lungs or loss of lung capacity four times faster than the normal rate a year after the accident.

Svendsen said some people are also suffering from post-traumatic stress disorder and react negatively to the sound of a train.

In calling for more participants, Svendsen noted that some people who didn’t show any symptoms have come in for testing, only to have clinical deficiencies discovered in their lung functions.