Quantitation by Portable Gas Chromatography: Mass Spectrometry of VOCs Associated with Vapor Intrusion

Development of a robust reliable technique that permits for the rapid quantitation of volatile organic chemicals is an important first step to remediation associated with vapor intrusion. This paper describes the development of an analytical method that allows for the rapid and precise identification and quantitation of halogenated and nonhalogenated contaminants commonly found within the ppbv level at sites where vapor intrusion is a concern. 1. Introduction Indoor air quality has become an ever increasing topic of interest in light of reports detailing building-related illnesses (“sick building syndrome”) that produce symptoms such as upper respiratory diseases, headaches, dizziness, and fatigue [1]. Indeed, the typical person spends approximately 90% of his day indoors [2]. A number of models have been proposed to address the processes in which indoor air contamination occurs via vapor intrusion [3–6]. In addition, environmental factors have been identified to include the following: proximity to source, presence of shallow ground water, soil type, fractured bedrock, chemical degradation (or oxidation), building construction style, as well as floor/utility line(s) condition [7]. Petroleum-based products and chlorinated hydrocarbons, as well as a variety of other volatile organic compounds (VOCs), can drift great distances above local water tables and enter dwellings via vapor intrusion from sources such as industrial sites or landfills [8–12]. Once an instance of vapor intrusion has been identified, monitoring the volatile organic chemicals contained in indoor air may be accomplished by following the compendium methods of the US EPA [13–15]; thus assisting to survey and mitigate the known hazard(s). These methods, which involve both passive and active sampling techniques, require time-consuming concentration periods and incorporate off-site laboratory analysis of multiple samples resulting in delayed overall analysis time [16]. The Massachusetts Department of Environmental Protection is one of a handful of US agencies to provide guidelines for long-term exposure to contaminated indoor air. Their defined limits, ranging from 0.001 to 187？ppbv per individual contaminate, provide the necessary guidance to incident commanders or super fund site coordinators to determine if a building is indeed fit to occupy once a site has been identified to suffer from sick building syndrome [17]. Field-portable instrumentation has been shown to offer rapid analysis of samples on site. Performing the chemical analysis onsite assists in eliminating sample integrity issues