DETERMINATION OF DNA-BENZO[A]PYRENE ADDUCTS BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH LASER-INDUCED FLUORESCENCE DETECTION

A method is described for the determination of tetrol metabolites (THBP) of benzo[a]pyrene adducts of DNA by HPLC with laser-induced fluorescence detection (HP-LC-LIF) after acid hydrolysis of the DNA-B[a]P adducts. Absolute detection limits at subfemtomole levels were obtained. Detection limits obtained on standard solutions of THBP using UV, conventional fluorescence detection, and laser-induced fluorescence detection methods are compared. The reproducibility of the HPLC-LIF method for the determination of DNA-B[a]P adducts at levels expected in fish exposed to benzo[a]pyrene was studied. The method was then applied to the determination of DNA-B[a]P adducts in fish injected with benzo[a]pyrene at different levels. Levels from 2 to 8 adducts per 10(8) normal nucleosides were found in fish liver DNA from fish injected with 25 mg of benzopyrene/kg of body weight.