Development of Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry Methods for Determination of Urinary Metabolites of Benzene in Humans

Dr. Melikian and colleagues at the American Health Foundation developed and validated a novel, practical method for assaying metabolites of benzene in humans methods using a technique known as Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry (LC-ESI-MS/MS) to measure benzene metabolites in human urine. The investigators measured S-phenylmercapturic acid (S-PMA) and trans,trans-muconic acid (t,t-MA) simultaneously; three other metabolites—p-hydroquinone (HQ), catechol (CAT), and 1,2,4-trihydroxybenzene (BT)— were assayed at the same time using a modification of the LC-ESI-MS/MS method. Because cigarette smokers have higher levels of some benzene metabolites than individuals not exposed, Dr. Melikian made preliminary assessments of the utility of her assays of benzene metabolites by measuring urinary levels in a group of smokers and in a control group of nonsmokers.