A simple and high collection efficiency sampling method for monitoring of carbonyl compounds in a workplace environment

Abstract

A simple and high collection efficiency sampling method was developed for the monitoring of carbonyl compounds, i.e., formaldehyde, acetaldehyde, benzaldehyde, acetone and butanone. The determination is based on the reaction of these compounds in a sensitive absorbing solution of 2,4–DNPH. After the completion of the reaction the derivatives were analyzed by the HPLC system without any post sample preparation. The operation conditions of the proposed method were optimized to obtain the highest sampling efficiency within a short analysis time. The collection efficiency for all compounds was in the range of 95 ± 3 % to 99 ± 4 % and the relative standard deviations (n = 15) were less than 10 %. This method was validated and applied to monitor carbonyl compounds in air samples from an occupational environment, the adhesive industry. Formaldehyde was found to be the most abundant carbonyl compound (64 ± 8 to 250 ± 20 ppbv), followed by acetaldehyde (ND to 24 ± 6 ppbv), acetone (ND to 21 ± 5 ppbv) and benzaldehyde (ND to 27 ± 7 ppbv). The sampling of air directly into the absorbing solution was compared with the conventional method of using an adsorbent cartridge, and the results were in good agreement (P > 0.05).

Keywords:

• Carbonyl compounds
• 2,4–dinitrophenylhydrazine
• absorbing solution
• HPLC

Acknowledgments

This project was supported by The Royal Golden Jubilee PhD–Program supported by The Thailand Research Fund; Center for Innovation in Chemistry (PERCH–CIC), Commission on Higher Education, Ministry of Education; The National Research University Project of Thailand, office of the Higher Education Commission; Trace Analysis and Biosensor Research Center, Graduate School, Faculty of Science, Prince of Songkla University, Hat Yai, Thailand. The authors thank Dr. Brian Hodgson, Prince of Songkla University, Hat Yai, Songkhla, Thailand for English proofreading.