Type de document
Communications orales
Date de la conférence
2024-10-21
Langue
Anglais
Nom de la conférence
ISES Annual Meeting 2024
Lieu de la conférence
Montréal, QC
Résumé
O-cresol in urine after hydrolysis is an exposure biomarker for toluene. This biomarker is volatile and routinely analyzed by gas chromatography−flame ionization detection (GC-FID) or gas chromatography−mass spectrometry (GC-MS). However, given the stringent sample preparation procedures required to ensure reliable GC-MS results, high-throughput sample analysis is not possible. In addition, the GC-FID detection limit for o-cresol in urine after hydrolysis is around 0.5 mg/L, while the ACGIH BEI is 0.3 mg/g cr (0.09 mg/L, if creatinine is 0.3 g/L; and 0.9 mg/L, if creatinine is 3 g/L). In other words, overexposure of some workers will not be detected by GC-FID as the detection limit is above the BEI set by ACGIH. Furthermore, GC-FID results are often inconclusive due to interference. This presentation, accordingly, describes a new alternative method that can measure as little as 10% of the ACGIH BEI and offer a throughput allowing results to be communicated to practitioners in less than 5 to 10 business days. O-cresol contain a functional group (hydroxyl group) that can react with dansyl chloride (dansylation reaction). This reaction allows conversion of the volatile o-cresol into non-volatile derivates compatible and enhanced with LC-MS/MS detection. The overall conditions established for this biomarker were validated based on AIHA LAP requirements for limits of detection and quantitation, intra-and inter-day precision, accuracy and recoveries. In addition, Clinchek QCs and interlaboratory proficiency tests from the G-EQUAS program were also performed. To our knowledge, our study is the first attempt to analyze o-cresol in urine after hydrolysis by LC-MS/MS.
Mots-clés
Test d'exposition, Exposure test, Effet biologique, Biological effect, Évaluation de l'exposition, Exposure evaluation, O-crésol, O-cresol, CAS 95487, Dosage dans l'urine, Determination in urine, 1-hydroxypyrène, 1-hydroxypyrene, CAS 5315797, Chromatographie en phase gazeuse, Gas chromatography, Spectrométrie de masse, Mass spectrometry
Numéro de projet IRSST
n/a
Citation recommandée
Gagné, S. et Langlois, É. (2024, 21 octobre). A new era in biological monitoring of toluene biomarker in urine through dansylation of o-cresol and LC-MS/MS analysis [Communication]. ISES Annual Meeting 2024, Montréal, QC.