title: Quantification of the urinary concentrations of parabens in humans by on-line solid phase extraction-high performance liquid chromatography-isotope dilution tandem mass spectrometry.
abstract: Parabens (alkyl esters of p-hydroxybenzoic acid) are widely used as antimicrobial preservatives in cosmetic products, pharmaceuticals, and food processing. However, weak estrogenicity of some parabens has been revealed from several studies. Human exposure to parabens may be assessed by measuring the conjugated or free species of these compounds or their metabolites in urine. We have developed a method using on-line solid phase extraction-high performance liquid chromatography-isotope dilution tandem mass spectrometry with peak focusing to measure the urinary concentrations of methyl, ethyl, propyl, n- and iso- butyl, and benzyl parabens. This method has good reproducibility and accuracy with detection limits for all analytes below 0.2ng/mL in 100microL of urine, and permits quick and accurate analysis of a large number of samples in epidemiologic studies for assessing the prevalence of human exposure to parabens. Using this method, we detected methyl, ethyl, and propyl parabens, mostly as conjugated species, in 22 urine samples collected from anonymous adults.
authors.affiliation: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Ye
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Kuklenyik
authors.forename: Amber M
authors.initials: AM
authors.lastname: Bishop
authors.forename: Larry L
authors.initials: LL
authors.lastname: Needham
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
mesh_terms: D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D010226:Parabens / Q000032:analysis*; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014556:Urine / Q000737:chemistry
chemical_list: D010226:Parabens