Capillary electrophoresis (CE) interfaced with low-temperature (4.2 K) fluorescence line-narrowing (FLN) spectroscopy is used for separation and structural characterization of polycyclic aromatic hydrocarbon-derived DNA adducts. The CE-FLN system is applied to the separation and identification of mixtures of benzo[a]pyrene and dibenzo[a,l]pyrene DNA adducts. Interfacing CE with FLN spectroscopy allows on-line separation and high-resolution spectroscopic identification of CE-separated DNA adducts, providing a new powerful tool for DNA adduct structure characterization.