| Title: | Matrix-effect-free determination of BTEX in variable soil compositions using room temperature ionic liquid co-solvents in static headspace gas chromatography mass spectrometry |
| Author(s): | Varona-Torres E; Carlton DD; Hildenbrand ZL; Schug KA; |
| Address: | "Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington TX, USA; Affiliate of the Collaborative Laboratories for Environmental Analysis and Remediation (CLEAR), The University of Texas at Arlington, Arlington TX, USA. Affiliate of the Collaborative Laboratories for Environmental Analysis and Remediation (CLEAR), The University of Texas at Arlington, Arlington TX, USA; Inform Environmental, LLC, Dallas TX, USA. Electronic address: zac@informenv.com. Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington TX, USA; Affiliate of the Collaborative Laboratories for Environmental Analysis and Remediation (CLEAR), The University of Texas at Arlington, Arlington TX, USA. Electronic address: kschug@uta.edu" |
| DOI: | 10.1016/j.aca.2018.03.017 |
| ISSN/ISBN: | 1873-4324 (Electronic) 0003-2670 (Linking) |
| Abstract: | "Concerns about the environmental impact of shale energy exploration (i.e., hydraulic fracturing and other well stimulation techniques) have risen due to its rapid expansion in the United States and other countries. Soils in shale basins engaged in unconventional oil and gas development can become contaminated by volatile organic compounds (VOCs), such as benzene, toluene, ethylbenzene, and xylenes (BTEX) through mishandling of chemical additives, products, and/or waste fluids. In this study, room temperature ionic liquids (RTILs) were evaluated as solvents in an effort to increase sensitivity and to reduce and normalize matrix effects associated with varying soil compositions during analysis. Headspace gas chromatography mass spectrometry (HS-GC-MS) experiments demonstrated that hydrophilic RTILs 1-ethyl-3-methylimidazolium ethyl sulfate [EMIM][ESO(4)], 1-ethyl-3-methylimidazolium diethyl phosphate [EMIM][DEP], and tris(2-hydroxyethyl) methylammonium methylsulfate [MTEOA][MeOSO(3)] normalized the response for BTEX compounds between 2 different soils, sandy loam and sandy clay loam. Furthermore, the optimization of the HS equilibration time to 30?ª+min resulted in the reduction of matrix effects in certified reference soils of sand, clay, and loam textures. Limits of detection and limits of quantification were in the sub- to mid- pg g(-1) level in soil. For determination at 1?ª+g of certified BTEX reference soil, the relative standard deviation was within 10% and percent recoveries were above 80% for toluene, ethylbenzene, and xylenes. This method reduces the need to characterize and matrix-match soil texture for calibration purposes. It also reduces the analysis time and increases precision and accuracy for the quantification of BTEX in variable soil matrices relative to standard methods" |
| Keywords: | Btex Environmental analysis Hydraulic fracturing Ionic liquids Matrix effects Soil; |
| Notes: | "PubMed-not-MEDLINEVarona-Torres, Emmanuel Carlton, Doug D Jr Hildenbrand, Zacariah L Schug, Kevin A eng Netherlands 2018/04/24 Anal Chim Acta. 2018 Aug 27; 1021:41-50. doi: 10.1016/j.aca.2018.03.017. Epub 2018 Mar 20" |
