Novel method to analysis benzo[a]pyrene in filter by liquid chromatography/tandem mass spectrometry: Application to assess mouth level benzo[a]pyrene exposure

Abstract

Benzo[a]pyrene (B[a]P) is a well-known carcinogenic compound produced from incomplete combustion of organic compounds. During cigarette smoking, cigarette filters trap a portion of mainstream smoke B[a]P and accurate measurement of B[a]P levels in cigarette filter can be used to estimate human exposure level of this compound. A rapid and sensitive method to quantify B[a]P levels trapped by cigarette filter was developed. The method is based on liquid chromatography/atmospheric pressure photoionization tandem mass spectrometry (LC/APPI-MS/MS). Validation was provided in smoked cigarette filter. The method involved no extensive manual cleanup and concentration steps, hence is easy to use. The limit of detection was 0.064 ng/mL. The recovery ranged from 82.68% to 103.27% and the relative standard deviation (RSD) was less than 7%. A regression model between mainstream cigarette smoke and trapped B[a]P by cigarette filter was established (y = 2.5089x - 0.1851, R(2) = 0.999, n = 6). This model was applied to estimate mouth-level B[a]P exposure of smokers. The LC/APPI-MS/MS method developed in this work had an excellent throughput in estimating the mouth-level exposure under natural human smoking conditions. Mouth-level B[a]P exposure based on a study of three cigarettes (8, 10 and 13 mg tar levels) showed significant positive correlations with B[a]P trapped by cigarette filter measured (y = 2.5456x - 0.5056, R(2) = 1, n = 249).