Real-Time Detection of PFAS in Air Using Chemical Ionization Mass Spectrometry

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Prepared by M. Abou-Ghanem, O. El Hajj, A. Koss, V. Pospisilova, S. Jorga
TOFWERK, 2760 29th St 2E, Boulder, CO, 80301, United States


Contact Information: [email protected]; 720-531-2529

ABSTRACT

Volatile per- and polyfluoroalkyl substances (PFAS) are increasingly recognized as emerging air pollutants due to their persistence, toxicity, and potential for long-range atmospheric transport. While regulatory efforts have primarily focused on PFAS contamination in water and soil, growing evidence indicates that consumer products, industrial materials, and thermal processes can release gas-phase PFAS. Despite this, PFAS in air remain poorly characterized, with limited real-time data on emission dynamics, atmospheric transformations, and the performance of thermal treatment technologies.

Previously, we demonstrated that the Vocus time-of-flight chemical ionization mass spectrometer (ToF-CIMS) enables highly sensitive measurements of a suite of volatile PFAS in air, with limits of detection in the sub–parts-per-trillion to parts-per-trillion range. Here, we expand on this work by demonstrating the versatility of this measurement technique across a range of laboratory and field applications, providing temporal resolution that is not achievable with conventional offline methods.

First, we apply this technique for high-throughput screening of consumer and industrial products, capturing real-time emission profiles of perfluoroalkyl carboxylic acids (PFCAs) and fluorotelomer alcohols (FTOHs). Second, we report results from a deployment at a waste-to-energy facility, where multiple PFAS—including trifluoroacetic acid (TFA), PFBA, PFHxA, and longer-chain analogues—were measured at concentrations ranging from tens to several hundred ppt, well below the detection limits of standard online techniques such as FTIR. Third, we present real-time monitoring of volatile PFAS during thermal remediation of aqueous film-forming foam (AFFF)–contaminated soil, enabling evaluation of treatment efficiency and emission characteristics. For all of these applications, we also discuss sampling challenges and background considerations.

These results highlight the broad utilization of CIMS for measurements of PFAS in air, demonstrating its potential to improve air quality monitoring and mitigation strategies for this group of compounds.