An alternative method to 32P-postlabeling has been proposed for sensitive detection and quantitation of deoxyguanosine monophosphate - benzo[a]pyrenediol epoxide (dGMP-BPDE), a biomarker for human exposure to carcinogenic polycyclic aromatic hydrocarbons (PAH), using capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). A modified CE-LIF instrument was adjusted to operate with a He/Cd UV laser (325 nm) for native fluorescence detection from BPDE adducts. The method was linear over three decades in concentration, with the detection limit of 2.5 × 10-9 mol L-1 at the signal-to-noise ratio of three after consecutive dilution of the dGMP-BPDE standard. At this level, recovery of 1 adduct per 10(7) normal nucleotides was possible. The RSD values for inter- and intra-day determination were better than 7% and recovery studies at three different levels yielded values around 50%. This method has been validated and for the first time applied to determination of dGMP-BPDE in blood samples from Brazilian rural workers, which were exposed to PAH in sugar-cane plantation harvesting and charcoal-production ovens.
BPDE; carcinogenic risk; capillary electrophoresis; environmental exposure
