Acrylonitrile and N,N-dimethylformamide – Determination of S-(2-cyanoethyl)mercapturic acid and S-(N-methylcarbamoyl)mercapturic acid in urine by LC-MS/MS

Biomonitoring Method – Translation of the German version from 2026

Elisabeth Eckert¹ (Method development)
  Thomas Göen¹ (Method development; Head of the working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
Rosa Mercadante² (External verification)
Franco Catuogno² (External verification)
Silvia Fustinoni² (External verification)
  Andrea Hartwig³ (Chair of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
  MAK Commission<sup>4

1</sup> Friedrich-Alexander-Universität Erlangen-Nürnberg, Institute and Outpatient Clinic of Occupational, Social, and Environmental Medicine, Henkestraße 9–11, 91054 Erlangen, Germany
² Laboratory of Environmental and Occupational Toxicology, Department of Clinical Sciences and Community Health, Dipartimento di Eccellenza 2023-2027, University of Milan, Via Francesco Sforza 35, 20122 Milano, Italy
³ Institute of Applied Biosciences, Department of Food Chemistry and Toxicology, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, Building 50.41, 76131 Karlsruhe, Germany
⁴ Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Germany

Abstract

The working group “Analyses in Biological Materials” of the German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) developed and verified this biomonitoring method for the simultaneous determination of the mercapturic acid of acrylonitrile (S‑(2‑cyanoethyl)mercapturic acid, CEMA) and that of N,N‑dimethylformamide (N‑acetyl-S‑(N‑methylcarbamoyl)cysteine, AMCC) in urine by LC‑MS/MS. For determination, the urine samples are buffered to a pH value of 2.5 and online enrichment is performed. Using integrated, automatic column-switching, the analytes are transferred in back-flush mode onto the analytical column and quantified by tandem mass spectrometry. Calibration is carried out using calibration standards prepared in pooled urine and processed analogously to the samples. The isotope-labelled mercapturic acids, CEMA‑D₃ and AMCC‑D₃, are used as internal standards. The method provides reliable and accurate analytical results, as shown by the good precision data with standard deviations no greater than 10%. Good accuracy data were obtained with mean relative recoveries in the range of 102–105%. Limits of quantitation of 6.0 μg CEMA/l and 7.5 μg AMCC/l were calculated. The method thus enables the biomonitoring of acrylonitrile and DMF in occupational and environmental exposure ranges.

---

---