This presentation will provide an overview of occurrence and sources of per- and polyfluoroalkyl substances (PFAS) in air with a focus on sampling and analytical techniques to identify and quantify known compounds of concern, and new compounds identified as products of incomplete combustion – an important consideration for emission management and destruction technology development.

PFAS are a group of synthetic chemicals that are used in various products and can be released into the air through industrial processes, waste treatment plants, and other sources. This can include volatile PFAS in the gas phase, or PFAS that have sorbed onto particulate.

Certain PFAS exhibit distinct volatility characteristics based on their chemical properties. For some compounds, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), their ability to partition from water into the air is restricted. Conversely other PFAS contain certain functional groups and properties that enhance their volatility, enabling them to more readily transition from aqueous environments into the atmosphere.

As global efforts intensify to reduce PFAS exposure, innovation in remediation technologies is accelerating. These technologies generally aim to:
• Remove PFAS-contaminated materials from the environment.
• Extract PFAS from those materials.

Once removed, PFAS waste is typically stored, landfilled, or destroyed to prevent re-exposure. Although new destruction methods are emerging, they lag remediation efforts. Industrial incineration, used for nearly a century, remains the most common large-scale PFAS destruction method. However, destruction efficiency (DE) is a key consideration for the implementation of this approach. At lower temperatures, fluorinated products of incomplete combustion (PICs) may form. If released, these PICs reintroduce PFAS into the environment and, as potent greenhouse gas (GHG) compounds, contribute significantly to the GHG impacts of incineration.

To monitor PFAS emissions, the U.S. EPA has developed two methods:
• OTM-45 (2021): Targets long and short chain PFAS using existing water methods and LC-MS/MS.
• OTM-50 (2024): Focuses on PICs and industrial compounds of interest including fluorinated refrigerants using evacuated canisters and GC-MS.

These methods aim to help operators and regulators assess emissions, verify destruction and mineralization, and guide process improvements. ALS has developed a method for non-polar volatile PFAS by canister based on the EPA OTM-50 method compound list and quality control criteria. The presentation will include details of the method development and data from initial field trials.