Biological monitoring of workers exposed to polychlorinated biphenyl compounds in capacitor accidents.

For biological monitoring of workers exposed to polychlorinated biphenyl (PCB) compounds, a gas-chromatographic method for analysis of PCBs in serum was developed. The quantitation is performed with 15 pure isomers, and extraction and concentration factors are corrected with the aid of asymmetric PCB compounds added to each specimen. By this method, humans with no known occupational exposure to PCB compounds showed PCB levels in serum that were always less than 3 micrograms/l. Workers exposed in capacitor accidents have shown maximal concentrations close to 50 micrograms/l.