Figure 3.

Chromatograms of phenolic metabolites. SIM chromatograms showing the separation of dihydroxylated (m/z 219) and monohydroxylated (m/z 203) metabolites of PCB3. A representative chromatogram of urine sample treated with sulfatase has been overlaid on the chromatogram of authentic standards to show different dihydroxylated metabolites formed in vivo. Chromatography was performed on a RP C18 column with an isocratic mobile phase of 80% acetonitrile in water (5 mM ammonium acetate) and a flow rate of 1 mL/min. This method could not separate isomers of monohydroxylated PCB3, and all isomers eluted as a single peak at 3.8 min. A peak at 1.9 min resulted from sulfate in the mixture of standards. Concentration of free phenolic forms was significantly lower than that of the conjugated forms in serum, urine, and bile.