Sampling of BTX in Hat Yai city using cost effective laboratory-built PCB passive sampler

ABSTRACT

A laboratory-built printed circuit board (PCB) passive sampler used for the monitoring of xylene and styrene in copy print shops was re-validated for detecting benzene, toluene and xylene (BTX) and applied for the sampling of ambient air from Hat Yai city, Songkhla, Thailand, in the month of November 2014. For monitoring, the PCB passive samplers were exposed to target analytes in 16 locations covering high to low exposure areas. After sampling, the samplers were thermally desorbed and the analytes were trapped by multi-walled carbon nanotubes packed into a micro-preconcentrator coupled to a gas chromatograph (GC) equipped with a flame ionization detector. At the optimum GC operating conditions, the linear dynamic ranges for BTX were 0.06–5.6 µg for benzene, 0.07–2.2 µg for toluene and 0.23–2.5 µg for xylene with R² > 0.99 with the limits of detection being 6.6, 6.8 and 19 ng for benzene, toluene and xylene, respectively. The concentrations of BTX in the 16 sampling sites were in the range of N.D.–1.3 ± 1.6, 4.50 ± 0.76–49.6 ± 3.7 and 1.00 ± 0.21–39.6 ± 3.1 µg m⁻³, respectively. When compared to past studies, there had been an increase in the benzene concentration.

KEYWORDS:

• BTX
• passive sampler
• PCB
• polypyrrole
• silver particles
• volatile organic compounds

Acknowledgments

The authors would like to thank Dr. Brian Hodgson for assistance with the English.

Funding

This project was supported by the Prince of Songkla University, Ph.D. Scholarship; Trace Analysis and Biosensor Research Center (TAB-RC); the Center of Excellence for Innovation in Chemistry (PERCH-CIC); Department of Chemistry, Faculty of Science and Graduate School, Prince of Songkla University, Hat Yai, Songkhla, Thailand.