Mixed Halogen Dioxins and Furans in Controlled Burn Samples Determined Using Gas Chromatography-Ion Mobility
Oral Presentation
Prepared by D. Stevens, A. Ladak
Waters Corporation, 34 Maple Street, Milford, MA, 01757, United States
Contact Information: [email protected]; 15084824672
ABSTRACT
Halogenated dioxins and furans are widely monitored persistent organic pollutants produced from a range of sources. They represent a highly varied group of compounds with respect to both degree of halogenation and position of chlorines and bromines. For risk assessment, the ability to determine the array of congeners present in samples is of particular interest. Here we propose the use of ion mobility separation (IMS) with QTof MS to characterize and isolate specific congener groups following GC separation. Complex burn site sample extracts containing mixed groups of dioxins and furans were used to assess this approach.
Atmospheric pressure ionization gas chromatography (APGC) with a 60m DB-5MS column was coupled to an IMS-QTof MS. Commercial standards of mixed halogen dioxins and furans were analyzed to determine retention times and accurate mass fragments. Controlled burn site samples from firefighter training were extracted using previously established methods for co-planar halogenated compounds.
Work completed so far demonstrates chromatographic separation of available standards using a single GC column. From these standards, accurate mass measured, fragment ions were acquired and their respective formulae confirmed from existing data or deduced for the first time. Additionally, drift times were measured for each analyte. Calibration of the IMS cell allowed collisional cross section (CCS) values to be determined resulting in an additional characteristic parameter associated with each analyte. Sample analyses were performed on the burn study extracts. Multiple congeners, in addition to those characterized from the available solvent standards, were observed. By using CCS, RT, parent and fragment accurate masses, combined with isotope patterns, the identification of additional congeners was possible. Spectral clean-up was also made possible by removing all spectral peaks that did not share the same drift time as the selected analyte. Combining GC with IMS and QTof demonstrates valuable new capabilities for this field of research.
Oral Presentation
Prepared by D. Stevens, A. Ladak
Waters Corporation, 34 Maple Street, Milford, MA, 01757, United States
Contact Information: [email protected]; 15084824672
ABSTRACT
Halogenated dioxins and furans are widely monitored persistent organic pollutants produced from a range of sources. They represent a highly varied group of compounds with respect to both degree of halogenation and position of chlorines and bromines. For risk assessment, the ability to determine the array of congeners present in samples is of particular interest. Here we propose the use of ion mobility separation (IMS) with QTof MS to characterize and isolate specific congener groups following GC separation. Complex burn site sample extracts containing mixed groups of dioxins and furans were used to assess this approach.
Atmospheric pressure ionization gas chromatography (APGC) with a 60m DB-5MS column was coupled to an IMS-QTof MS. Commercial standards of mixed halogen dioxins and furans were analyzed to determine retention times and accurate mass fragments. Controlled burn site samples from firefighter training were extracted using previously established methods for co-planar halogenated compounds.
Work completed so far demonstrates chromatographic separation of available standards using a single GC column. From these standards, accurate mass measured, fragment ions were acquired and their respective formulae confirmed from existing data or deduced for the first time. Additionally, drift times were measured for each analyte. Calibration of the IMS cell allowed collisional cross section (CCS) values to be determined resulting in an additional characteristic parameter associated with each analyte. Sample analyses were performed on the burn study extracts. Multiple congeners, in addition to those characterized from the available solvent standards, were observed. By using CCS, RT, parent and fragment accurate masses, combined with isotope patterns, the identification of additional congeners was possible. Spectral clean-up was also made possible by removing all spectral peaks that did not share the same drift time as the selected analyte. Combining GC with IMS and QTof demonstrates valuable new capabilities for this field of research.
