Rapid Quantification of Per- and Polyfluoroalkyl Substances by Combustion Gas Analysis

Highlights of SERDP- and ESTCP-Funded Projects
Oral Presentation

Prepared by I. Abusallout, J. Wang, D. Hanigan
University of Nevada, Reno, 1664 N Virginia St, Reno, Nevada, 89557, United States


Contact Information: [email protected]; 605-690-9243


ABSTRACT

Per- and Polyfluoroalkyl Substances (PFASs) are class of man-made chemicals that have been widely used in various industrial processes and products including fire-fighting foams. In addition to their global widespread application, PFASs are environmentally stable and therefore have been detected in waters, sediments and atmosphere. There is evidence that exposure to PFASs can lead to adverse health outcomes in humans. Therefore, the U.S. Environmental Protection Agency has set health advisory levels for the most two abundant PFASs to protect public health. Sampling and quantifying PFASs is required to remediate contaminated sites, but the process is time-consuming, requires costly instrumentation and expertise (LC-MS/MS), and fails to capture many organofluorine transformation products and precursors that may also pose health hazards for the public. The objective of this study is to develop and validate field-ready instrumentation to quantify total organofluorine through combustion gas analysis.
We will present our initial studies that investigate the use of commercially available Shimadzu TOC instrumentation as the combustion furnace. These instruments are extremely common in environmental engineering and science labs and thus we expect to develop an Application Note with Shimadzu on the modification procedures that were used. We compared two combustion oven temperatures (720 ? vs 900 ?) that are relatively easily modified through Shimadzu software changes, and we investigated multiple carrier gas flow rates and gas flow routing to minimize losses. This presentation will also focus on capturing the combusted fluorine via alkaline impingers. Although our goal is to eventually mate the combustion instrument to a gas analyzer, we first must ensure complete combustion through capturing fluorine as aqueous fluoride and analyzing using simpler ion chromatography or Hach UV/Vis methods. We believe these results will be valuable to many labs who already own a TOC and an IC instrument, because the modifications will allow for total fluorine quantification with a relatively small investment.