Analytical methods for the determination of biomarkers of exposure to phthalates in human urine samples

This study presents an overview of the analytical methods for the determination of biomarkers of exposure to phthalates in human urine samples. Phthalates are nonpersistent chemicals; hence, urine is the ideal matrix for biomonitoring besides being noninvasive and simple to collect. Phthalate monoesters and oxidative secondary metabolites are the suitable biomarkers of exposure to short- and long-chain phthalates, respectively. The determination of urinary phthalate metabolites significantly reduces the “phthalate blank problem,” which arises due to the ubiquitous presence of this chemical compound in laboratory atmosphere. Sample preparation and analytical methodologies for the determination of urinary phthalate metabolites by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography- tandem mass spectrometry (LC-MS/MS) techniques were discussed. Issues on the validity of urinary phthalate metabolite data, such as intra- and interpersonal variations, variability in population subgroups, and variability due to time and type of urine sample collection, are discussed. Measures to minimize uncertainties associated with urinary phthalate metabolite concentration are also suggested.