title: Analysis of dialkyl phosphate metabolites in hair using gas chromatography-mass spectrometry: a biomarker of chronic exposure to organophosphate pesticides.
abstract: The aim of our study was to develop and validate an analytical approach for the quantitative determination of three dialkyl phosphate (DAP) metabolites, dimethyl phosphate (DMP), dimethyl thiophosphate (DMTP) and diethyl phosphate (DEP), of organophosphate pesticides (OPs) in hair samples. The proposed methodology comprises a decontamination step, solid-liquid extraction, followed by liquid-liquid extraction, pentafluorobenzyl bromide derivatization, clean-up on Florisil/PSA column and analysis by gas chromatography-mass spectrometry (GC-MS). Extraction recovery, obtained from 50 mg hair samples spiked at two concentration levels, ranged from 56.1 to 107.9% and the within-day precision ranged from 13.5 to 17.5%. Limits of detection (LODs) ranged from 0.02 to 0.10 ng mg(-1). The results obtained from the analysis of hair samples of 30 agricultural workers show the suitability of the proposed method for monitoring people occupationally exposed to OPs. The most frequently detected compound was DEP followed by DMP. This is the first report on the detection of dialkyl phosphates in human hair which reflects the ability of hair testing to assess chronic exposure to OPs.
authors.affiliation: Department of Medicine, Centre of Toxicological Sciences and Research, Medical School, University of Crete, Heraklion, Crete, Greece.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Margariti
authors.forename: Aristidis M
authors.initials: AM
authors.lastname: Tsatsakis
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D009943:Organophosphorus Compounds / Q000633:toxicity*; D010575:Pesticides / Q000633:toxicity*; D010710:Phosphates / Q000032:analysis*; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D009943:Organophosphorus Compounds; D010575:Pesticides; D010710:Phosphates