Stationary Source Sampling and Analysis of Semi-volatile Polar and Volatile PFAS – Other Test Methods (OTM) 45 and 50 [Presentation]
On this page:
Per- and polyfluorinated alkyl substances (PFAS) are synthetic chemicals that possess a strong carbon-fluorine backbone and diverse functional head groups that impart unique physical and chemical properties. Such properties have made PFAS useful in food-contact materials, firefighting foams, and stain repellants. Maintained databases of PFAS have cited that there are over 4,700 unique compounds in existence, where at least 1,364 compounds have been identified in commercial uses in the United States. PFAS can also be released into the environment from landfills, chemical production plants, and incinerators. Unfortunately, these fluorochemicals have a widespread presence and persistence in the environment and are associated with adverse health effects. An active area of PFAS investigation is in stationary source emissions from industrial facilities to ensure that PFAS are fully mineralized and that products of incomplete combustion (PICs) which could impact human and environmental health are not released. Sampling methods have been developed by scientists within the U.S. Environmental Protection Agency (EPA) to monitor PFAS emissions from stationary sources. These Other Test Methods (OTMs) are performance-based approaches that assess targeted lists of semivolatile polar or very volatile non-polar PFAS in OTM-45 and OTM-50, respectively. OTM-45 incorporates gaseous and particulate-bound media with liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection for 49 PFAS, including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), and was released for public use in January 2021. While still in development, OTM-50 collects emissions samples in evacuated 6L stainless-steel canisters to quantify 30 volatile fluorochemicals and greenhouse gases, such as tetrafluoromethane (CF4) and 1H-perfluorooctane, using gas chromatography-mass spectrometry (GC-MS). This presentation will provide an overview of each sampling and analytical method as well as best practices and lessons learned from application in the field. The views expressed in this abstract are those of the authors and do not necessarily represent the views and policies of the U.S. EPA.