title: Application of CSIA to distinguish between vapor intrusion and indoor sources of VOCs.
abstract: At buildings with potential for vapor intrusion of volatile organic chemicals (VOCs) from the subsurface, the ability to accurately distinguish between vapor intrusion and indoor sources of VOCs is needed to support accurate and efficient vapor intrusion investigations. We have developed a method for application of compound-specific stable isotope analysis (CSIA) for this purpose that uses an adsorbent sampler to obtain sufficient sample mass from the air for analysis. Application of this method to five residences near Hill Air Force Base in Utah indicates that subsurface and indoor sources of tricholorethene and tetrachloroethene often exhibit distinct carbon and chlorine isotope ratios. The differences in isotope ratios between indoor and subsurface sources can be used to identify the source of these chemicals when they are present in indoor air.
authors.affiliation: GSI Environmental, Houston, Texas, USA. temchugh@gsi-net.com
authors.forename: Thomas
authors.initials: T
authors.lastname: McHugh
authors.forename: Tomasz
authors.initials: T
authors.lastname: Kuder
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fiorenza
authors.forename: Kyle
authors.initials: K
authors.lastname: Gorder
authors.forename: Erik
authors.initials: E
authors.lastname: Dettenmaier
authors.forename: Paul
authors.initials: P
authors.lastname: Philp
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D002247:Carbon Isotopes / Q000032:analysis; D002713:Chlorine / Q000032:analysis / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D005740:Gases / Q000737:chemistry*; D006798:Housing; D013750:Tetrachloroethylene / Q000032:analysis; D014241:Trichloroethylene / Q000032:analysis; D014589:Utah; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D002247:Carbon Isotopes; D005740:Gases; D055549:Volatile Organic Compounds; D014241:Trichloroethylene; D002713:Chlorine; D013750:Tetrachloroethylene