Amines – Determination of N,N-dimethylethylamine, N,N-dimethylisopropylamine, N,N-dimethyl-n-propylamine and triethylamine in workplace air using ion chromatography (IC)

Air monitoring method – Translation of the German version from 2024

Christiane Kaus¹ (method development)
Wilhelm Krämer² (external verification)
Ralf Schmitt² (external verification)
  Ralph Hebisch³ (Head of the working group “Air Analyses” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
  Thomas Helmut Brock⁴ (Head of the working group “Analytics”)
  Andrea Hartwig⁵ (Chair of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, Deutsche Forschungsgemeinschaft)
  MAK Commission<sup>6

1</sup> Institut für Arbeitsschutz der DGUV (IFA), Deutsche Gesetzliche Unfallversicherung e.V. (DGUV), Alte Heerstraße 111, 53757 Sankt Augustin, Germany
² BASF SE, Carl-Bosch-Straße 38, 67056 Ludwigshafen, Germany
³ Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA), Friedrich-Henkel-Weg 1–25, 44149 Dortmund, Germany
⁴ German Social Accident Insurance, Institution for the raw materials and chemical industry, Prevention - Department of Hazardous Substances, Biological Agents and Analytical Chemistry, Kurfürsten-Analge 62, 69115 Heidelberg, Germany
⁵ Institut für Angewandte Biowissenschaften, Abteilung Lebensmittelchemie und Toxikologie, Karlsruher Institut für Technologie (KIT), Adenauerring 20a, Geb. 50.41, 76131 Karlsruhe, Germany
⁶ Ständige Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Germany

Abstract

The working group “Air Analyses” of the German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) developed and verified the presented analytical method. This analytical method is a validated measurement procedure for the determination of N,N-dimethylethylamine [598-56-1], N,N-dimethylisopropylamine [996-35-0], N,N-dimethyl-n-propylamine [926-63-6] and triethylamine [121-44-8] in workplace air. The concentration ranges cover one tenth up to twice the currently valid occupational exposure limit values in Germany (OELV) of 6.1 mg/m³ for N,N-dimethylethylamine, of 3.6 mg/m³ for N,N-dimethylisopropylamine and of 4.2 mg/m³ for triethylamine. For N,N-dimethyl-n-propylamine the same OELV as for trimethylamine was anticipated. For sampling, a defined volume of air is drawn through an acid-impregnated quartz fibre filter. The flow rate is set to 0.5 l/min and sampling duration is 2 hours (which corresponds to a sampling volume of 60 l). The amines are extracted with 10 mM methanesulfonic acid solution and subsequently analysed using ion chromatography with conductivity detection. The quantitative determination is based on a cubic calibration function. The limits of quantification are between 0.022 and 0.047 mg/m³ based on an air sample volume of 60 l and an extraction volume of 10 ml. The recoveries are between 77 and 86%. The expanded uncertainties for the validation range are between 13.2 and 16.8%.

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