Identification of benzo(a)pyrene metabolites by gas chromatograph-mass spectrometer.

A gas chromatograph-mass spectrometer was used in an attempt to achieve rapid separation and accurate identification of benzo(a)pyrene and its synthesized derivatives. All derivatives, after being trimethylsilylated, were developed on Dexsil-300 and OV-1 columns. The seven diols and four stereoisomeric 7,8,9,10-tetraols studied were separated successfully. The separation of the 12 phenols was unsatisfactory; 8- and 11-isomers appeared separately but the other 10 isomers made 3 peaks on the OV-1 column. Among the five derivatives reported to be present in animal tissues, 6-, 7-, and 9-phenols were separated, but 1- and 3-phenols were fused on the Dexsil-300 column. Quinones were converted to related dihydroxyl derivatives under silylation. The chromatographic separation of four of the six dihydroxyl derivatives was successful on the OV-1 column, but the 6,12- and 7,10-isomers remained in a single peak. The two diol-epoxides were unstable under silylation and therefore were detected by their breakdown products, 7,8,9-trihydroxy-7,8-dihydrobenzo(a)pyrene and tetraols. Data are listed on the mass spectra and retention times of all benzo(a)pyrene derivatives studied.