Lessons Learned During Environmental Forensic Investigation of Chemical Manufacturing and Use of PFAS by Non-targeted Analysis

Advances in High Resolution Mass Spectrometry and Its Emerging Environmental Applications
Oral Presentation

Prepared by M. Strynar
US EPA, 109 Tw Alexander Dr, Durham, NC, 27709, United States


Contact Information: [email protected]; 919-541-3706


ABSTRACT

The intersection between high resolution mass spectrometry (HRMS), non-targeted analysis (NTA) and per- and polyfluoroalkyl substances (PFAS) brings three complex topics together. Over the past several years we have obtained samples of industrial effluent and contaminated surface, ground, and wastewater from numerous collaborations with state and regional EPA offices investigating the presence of legacy and emerging PFAS chemistries. NTA using HRMS (e.g. QTOF or Orbitrap) was used to examine the chemical identities of PFAS within these samples and compare the abundances of legacy and emerging chemical contaminants. Through this approach we have been able to identify legacy contaminants of use, as well as elucidate alternative PFAS used by a variety of chemical manufacturers. These include previously unidentified family of chlorinated perfluoropolyethers (Cl-PFECAs), polyfluorinated side products of polyfluorovinylidine (PVDF), as well as several other novel PFAS fluoroether species exhibiting ether linkages and acid head groups. This presentation will discuss lessons learned while conducting case studies PFAS site investigations. Topics will include decisions concerning sample preparation and analysis conditions, isolation of PFAS from large data files, prioritization of detected chemicals, data reduction strategies, alternative data mining techniques and determination of data analysis completion. In many instances there is no “one size fits all” approach for the above decisions being made. However shared experiences with the greater scientific community may benefit veteran and novice investigators.