Analysis of Indoor Microbial Volatile Organic Compounds by Solid-Phase Microextraction with GC/MS under Nonequilibrium Situation

• Main Authors: Wan-Chen Lee, 李婉甄
• Other Authors: Shih-Wei Tsai
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/99333002681942536652

碩士 === 國立臺灣大學 === 環境衛生研究所 === 96 === More emphasis has been placed on mold in recent years because exposure to indoor mold can cause adverse health effects in human. Microbial Volatile Organic Compounds (MVOCs) are chemicals generated by molds during their life cycle and can be used as markers for mold growth indoors because they can diffuse through building materials which can not be penetrated by mold spores. And positive associations have also been found between the exposures of MVOCs and asthma or allergy. Therefore, the objective of this research was to develop a dynamic sampling method which is rapid and sensitive enough for the determination of MVOCs with solid-phase microextraction (SPME) technique. Three SPME fibers were evaluated in this study for their suitability in sampling seven commonly seen mold indoors in Taiwan, including 2-methyl-1-propanol, 1-butanol, 3-methyl-1-butanol, 2-hexanone, 2-heptanone, 1-octen-3-ol, and 2-pentylfuran. The dynamic sampling system which produced a constant flow of known concentration of MVOC vapor was used for rapid sampling. After sampling, the SPME fiber was inserted to the injection port of gas chromatograph with mass spectrometer (GC/MS) for thermal desorption and further analysis. Results showed that the Carboxen/PDMS fiber was found to be the most suitable among the three fibers for MVOCs sampling. Sampling with Carboxen/PDMS also presented a good linearity between mass collected on fiber and the magnitude of exposure (in concentration-time units). In addition, when sampling for 40 min from 0.8 μg/m3 to 8μg/m3, no competitive adsorption occurred. And the experimental sampling rates were 0.0884±0.0038 cm3/s for 2-methyl-1-propanol, 0.1231±0.0024 cm3/s for 1-butanol, 0.0268±0.0008 cm3/s for 3-methyl-1-butanol, 0.0355±0.0005 cm3/s for 2-hexanone, 0.1379±0.0062 cm3/s for 2-heptanone, 0.0253±0.0044 cm3/s for 1-octen-3-ol, and 0.0748±0.002 cm3/s for 2-pentylfuran. This study demonstrated the potential of using Carboxen/PDMS fiber for analysis of MVOCs under nonequilibrium conditions, which possesses the advantages of the SPME technique. And the sampling rates determined in this study can possibly be applied in the future for field study.