Abstract
Formaldehyde was monitored in the workplace environment of an adhesive manufacturer producing formaldehyde and urea-formaldehyde resin using a cost-effective sol-gel-based sensor. The sensor was first evaluated by comparing its performance to the conventional 2,4-dinitrophynylhydrazine-devivatization method (2,4-DNPH) followed by high-performance liquid chromatography coupled to a UV detector. The formaldehyde concentrations obtained by both techniques were not significantly different. The cost-effective sol-gel-based sensor was then used for monitoring formaldehyde levels in the laboratories, production areas and storage room. Formaldehyde concentrations in this adhesive manufacturer workplace environment were lower than the limit value of, 0.75 ppm for an 8-h time weight average and 2 ppm for a short-term exposure (15 min). However, the cancer risk for employees who worked in the laboratories, (1.7±0.7)×10−4–(5±2)×10−4, were higher than the acceptable cancer risk recommended by the US EPA (10−6). Therefore, some precaution should be taken to reduce the risk, such as an increase of ventilation to dilute the levels of formaldehyde and use air cleaners to remove formaldehyde.
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 assistance with the English.