Studies on an efficient method for determining ethyl carbamate in the workplace air

In relation to the proposal to introduce an occupational exposure limit value for ethyl carbamate (EC) in Poland, a need to develop a sensitive method for determination of this carcinogenic substance in the workplace air was emerged. In the presented paper, a new method for its determination by high-performance liquid chromatography (HPLC) with fluorescence detector (FLD) is proposed. The method is based on the adsorption of EC on the cellulose filter, its extraction with water, further reaction of EC with 9-xanthydrol in acidic solution. Determination of the obtained EC derivative (N-xanthyl ethyl carbamate) was then conducted in a reverse-phase system with acetonitrile and water mobile phase at a flow rate of 1 mL/min on an Ultra C18 column of 250 mm by HPLC–FLD. Measurement range of 0.1–2 µg/m³ for a 1440 L of air sample was appropriate to the established maximum admissible concentration value of 1 µg/m³. The limit of detection is 0.142 ng/mL, and the limit of quantification is 0.426 ng/mL, respectively. The developed quantitative method makes it possible to determine ethyl carbamate in workplace air, which in turn allows determining exposure indicators and facilitates occupational risk assessment for the employees.