title: Simultaneous determination of six dialkylphosphates in urine by liquid chromatography tandem mass spectrometry.
abstract: Dialkylphosphates (DAP) are urinary markers of the exposure to organophosphates pesticides. The aim of this study was to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantitative determination of the following DAP: dimethylphosphate (DMP), dimethythiophosphate (DMTP), dimethyldithiophosphate (DMDTP), diethylphosphate (DEP), diethylthiophosphate (DETP) and diethyldithiophosphate (DEDTP). Dibutylphosphate (DBP) was used as internal standard. This method was based on a liquid-liquid extraction procedure, a chromatographic separation using an Inertsil ODS3 C18 column and mass spectrometric detection in the negative ion, multiple reaction monitoring (MRM) mode, following two ion transitions per compound. It yielded a limit of quantification of 2 microg/L for the six compounds and intra-assay coefficients of variation (CV%) lower than 20%. This method was applied to the analysis of urines samples from a small cohort of non-exposed volunteers. At least one of the six DAP was detected in each sample. This result confirmed the feasibility of a LC-MS/MS procedure for monitoring the general population exposure to some frequently employed organophosphate pesticides.
authors.affiliation: Department of Pharmacology and Toxicology, University Hospital, 2 Avenue Martin Luther King, 87042 Limoges, France.
authors.forename: S
authors.initials: S
authors.lastname: Dulaurent
authors.forename: F
authors.initials: F
authors.lastname: Saint-Marcoux
authors.forename: P
authors.initials: P
authors.lastname: Marquet
authors.forename: G
authors.initials: G
authors.lastname: Lachâtre
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004781:Environmental Exposure / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008875:Middle Aged; D010755:Organophosphates / Q000652:urine*; D010573:Pesticide Residues / Q000652:urine
chemical_list: D010755:Organophosphates; D010573:Pesticide Residues