Persistently elevated polychlorinated biphenyl levels from residual contamination of workplace surfaces

A short-term follow-up study was performed on 55 workers in a gear plant exposed to PCB that contaminated the work surfaces. Current work did not involve the use of PCBs. Exposure was to residual PCB left behind by a capacitor company which formerly used the site. Elevated PCB levels were found in production area workers; these elevations persisted on retesting 1 year later. Efforts should be made to identify potentially toxic materials left behind on work surfaces of buildings before remodeling or reuse.