Application of CSIA to Distinguish Between Vapor Intrusion and Indoor Sources of VOCs

• Published in: Environmental science & technology Vol. 45; no. 14; pp. 5952 - 5958
• Main Authors: McHugh, Thomas, Kuder, Tomasz, Fiorenza, Stephanie, Gorder, Kyle, Dettenmaier, Erik, Philp, Paul
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.07.2011
• Subjects: Adsorbents; Air Pollution, Indoor - analysis; Applied sciences; Atmospheric pollution; Buildings. Public works; Carbon Isotopes - analysis; Characterization of Natural and Affected Environments; Chlorine - analysis; Chlorine - chemistry; Environmental science; Exact sciences and technology; Gas Chromatography-Mass Spectrometry; Gases - chemistry; Housing; Indoor air quality; Indoor pollution and occupational exposure; Isotopes; Organic chemicals; Pollution; Pollution indoor buildings; Tetrachloroethylene - analysis; Trichloroethylene - analysis; Utah; VOCs; Volatile organic compounds; Volatile Organic Compounds - analysis; United States; North America; Utah; America; United States > US; USA, Utah; Isotopic analysis; Volatile organic compound; Identification; Ethylene(tetrachloro); Organic solvent; Investigation method; Source localization; Chlorocarbon; Stable isotopes; Indoor pollution; Subsurface; Organic compounds; Ethylene(trichloro)
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es200988d

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.