OKLAHOMA CITY (AP) -- Blood samples taken from workers at an Army ammunition plant that makes bombs for the U.S. military show workers have been exposed to a powder explosive that causes anemia, despite efforts to curb the exposure.
Officials with the McAlester Army Ammunition plant said Tuesday that workers on the bomb line that makes the 2,000-pound "bunker-buster" bombs for the Air Force have tested positive for TNT exposure, said Mark Hughes, plant spokesman.
Operations on the bomb line shut down Tuesday, according to a news release from the plant. Exposure levels of TNT were well below federal U.S. Occupational Safety and Health Administration guidelines. But the bomb-making line was shut down after blood tests showed workers had low levels of oxygen in their blood, caused by exposure to TNT.
This comes after nearly $350,000 in improvements were made to the building were the bombs are filled, including the addition of an air scrubber that was supposed to remove the powdered explosive from the air.
"We did not achieve all the results we had hoped to achieve with the measures we put in place," said a news release from the plant.
Anemia can cause fatigue, headaches and reduced stamina. Ammunition plant officials say they don't expect workers to have any lingering health problems.
Workers first tested positive for TNT exposure in September, just a month after they started making the bunker buster bombs for the Air Force. The production line closed after 34 employees tested positive for TNT-related anemia.
An employee's visit to his private physician for back trouble alerted plant officials to the TNT exposure.
At the time, plant officials believed dust laden with explosive powder settled on workers who were sweating in the non-air conditioned building at the ammunition plant in southeastern Oklahoma. As result of the exposure, workers were required to shower before leaving work.
Bomb production in the building resumed in January after improvements were made to the building. Workers were then required to wear respirators, gloves, hats and long-sleeved coveralls. Only the backs of their necks and their checks would have been exposed while they worked 10-hour shifts filling bombs.
"Despite significant improvements in ventilation, architectural design and administrative controls...we detected unexpected trends toward abnormal blood...values in our workers," the release said.
The ammunition plant makes bombs for the U.S. military and employs about 1,400 people from McAlester and the surrounding areas.
The bunker buster line is the only bombing making line at the plant that fills the bomb casings with a powder explosive. The rest of the lines use a clay-like explosive, Hughes said.