But-2-enal. Determination in workplace air

Abstract

But-2-enal (crotonaldehyde) is a colourless liquid with an unpleasant suffocating odour. But-2-enal occurs naturally in food. It is mainly used for the production of sorbic acid, a food preservative. But-2-enal is a very toxic, highly irritating and allergenic substance – it is suspected of causing genetic defects. The aim of the study was to develop a method for determination of but-2-enal, which will enable determination of concentrations of this substance in the workplace air in the range from 1/10 to 2 MAC values. The tests were performed using a liquid chromatograph (HPLC) with a diode array detector (DAD), equipped with an Ultra C18 column (250 x 4.6 mm; 5 μm). The method consists in retaining the but-2-enal on a silica gel coated with 2,4-dinitrophenylhydrazine. The sample is extracted with acetonitrile and analyzed by HPLC. Validation of the method was carried out in accordance with the requirements of the European standard EN 482. The measuring range of the method is from 0.1 to 2 mg/m3 for a 12 l sample of air. The following validation parameters were obtained: limit of detection: 1.26 ng/ml (0.21 μg/m3), limit of quantification: 3.77 ng/ml (0.63 μg/m3), the overall accuracy of the method: 5.08%, expanded uncertainty: 22%. The developed analytical method enables selective determination of but-2-enal in workplace air at concentrations ranging from 0.1 mg/m3, i.e. from 1/10 of the MAC value in the presence of co-occurring substances. The method is characterized by good precision and accuracy and meets the requirements of the European standard PN-EN 482 for procedures for determination of chemical agents. The developed method of determining but-2-enal has been recorded as an analytical procedure (see Appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.