Biomonitoring of occupational exposure to 5-FU by assaying α-fluoro-β-alanine in urine with a highly sensitive UHPLC-MS/MS method.

5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs handled by healthcare professionals (HCP). To monitor occupational exposure to 5-FU, a highly sensitive ESI-UHPLC-MS/MS method was developed for the assay of its main human metabolite, α-fluoro-β-alanine (FBAL), in urine. After a derivatization step, solid phase extraction was used for the urine.