title: Identification of sink spots in two thermal desorption GC/MS systems for the analysis of polycyclic aromatic hydrocarbons.
abstract: Thermal desorption (TD) GC/MS has been used for the analysis of polycyclic aromatic hydrocarbons (PAHs) and other semi-volatile organic compounds. However, thermal desorption recovery of PAHs have not been well studied and the cause of PAH residues in a TD system has not been clearly understood. Our results showed that low volatility of PAHs can lead to their incomplete recovery in a TD system: for the PAHs with low vapour pressures, up to 10% and 3% could be lost in a two-stage (TS) TD system and a short-path (SP) TD system, respectively. Within the TSTD system, the majority of residues were found in the 4-port valve and in the spot where internal trap and the 4-port valve connects. Within the SPTD system, residues were largely confined to the tube needle connecting the sample tube and GC injection port as well as inside the injection port. Since the volatility of PAHs can represent the range typical of semi-volatile organic compounds (SVOCs), our results have a wide implication for the thermal desorption of SVOCs in general.
authors.affiliation: Exposure and Biomonitoring Division, Health Canada, Ottawa, Ontario, K1M2A2, Canada; Shanghai Academy of Environmental Sciences, Shanghai, 200233, China; State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai, 200233, China; College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Li
authors.affiliation: Exposure and Biomonitoring Division, Health Canada, Ottawa, Ontario, K1M2A2, Canada. Electronic address: jiping.zhu@canada.ca.
authors.forename: Jiping
authors.initials: J
authors.lastname: Zhu
keywords: Deposition; GC/MS; Polycyclic aromatic hydrocarbon; Recovery; Thermal desorption