WRIGHT-PATTERSON AIR FORCE BASE — Five people at the base were contaminated with mercury Friday afternoon after a contractor employee cleaning out a storage container encountered the mercury, a base spokeswoman said.

The contractor employee and four firefighters who responded from the Wright-Patterson Air Force Base fire department were contaminated with the mercury, base spokeswoman Rachel Castle said.

The five were decontaminated at the scene and appeared to be OK, Castle said. Their health will be monitored as a precaution, she said.

The employee was cleaning sludge out of the container before realizing that it contained mercury, Castle said. The accident occurred shortly before 4:30 p.m. while the employee was working in a manhole outside Building 18, a propulsion technology complex in the base's Area B, Castle said.

Wright-Patterson sent firefighters and its hazardous-materials response team to the scene.

Exposure to mercury can affect the nervous system, causing weakness, fatigue and loss of appetite. It can also damage the kidneys.