A Simple Method to Determine Azobenzene in the Workplace Air

Abstract

Background: In view of the exposure of workers in Poland to azobenzene, there is a need to develop a sensitive method for the determination of this carcinogen in the air. The determination method proposed in this article is simple, using high-performance liquid chromatography with diode array detection.
Material and methods: The method consists of the adsorption of azobenzene using a cellulose filter and silica gel, followed by its extraction with methanol, and an analysis of the received solutions. The methanol as the mobile phase at a flow rate of 0.6 mL min-1 and an Ultra C18 column of 250 mm length at the temperature of 298 K were used for chromatographic separation.
Results: The use of diode array detector at a wavelength of 316 nm makes it possible to quantitatively determine 2 micrograms of azobenzene in a cubic meter of the workplace air (for 120 L air samples) under the conditions of air sampling and determination described in the procedure. The limit of detection is 3.1 ng mL-1, and the limit of quantification is 9.4 ng mL-1.
Conclusions: The method could be useful for determining concentrations of azobenzene in workplace air to assess occupational exposure to this hazardous substance at the workplace.