Brent Pautler, PhD, Alexander Sweett, and Jeff Roberts coauthored “A field-validated equilibrium passive sampler for the monitoring of per- and polyfluoroalkyl substances (PFAS) in sediment pore water and surface water” in the May 2023 edition of Environmental Science: Processes & Impact.
Brent received his doctorate degree in environmental analytical chemistry in 2013, during which time he gained advanced technical experience in spectroscopy, chromatography, mass spectrometry, passive sampling, and chemistry informatics. Throughout his career, he has worked with scientists, engineers, and consultants, applying his chemistry and information technology expertise to help them solve unique problems in the laboratory and the field.
Alexander is an Analytical Technician in SiREM’s environmental lab. There he focuses on passive samplers. He graduated from University of Guelph with a degree in chemistry, where he gained knowledge on computational research and analytical chemistry.
Jeff is the Operations Manager at SiREM. He brings extensive technical experience in the laboratory assessment and field implementation of soil, sediment and groundwater remediation technologies at sites containing contaminants including chlorinated solvents, petroleum hydrocarbons, emerging contaminants, and other recalcitrant compounds.
Environmental Science: Processes & Impacts is a multidisciplinary journal for the environmental chemical sciences. It is one of 54 peer-reviewed journals published by the Royal Society of Chemistry, which covers the core chemical sciences including the related fields of biology, biophysics, energy and environment, engineering, materials, medicine, and physics.
A simple equilibrium passive sampler, consisting of water in an inert container capped with a rate-limiting barrier, for the monitoring of PFAS in sediment pore water and surface water was developed and tested through a series of laboratory and field experiments. The objectives of the laboratory experiments were to determine (1) the membrane type that could serve as the sampler’s rate-limiting barrier; (2) the mass transfer coefficient of environmentally relevant PFAS through the selected membrane; and (3) the performance reference compounds (PRCs) that could be used to infer the kinetics of PFAS diffusing into the sampler. Of the membranes tested, the polycarbonate (PC) membrane was deemed the most suitable rate-limiting barrier, given that it did not appreciably adsorb the studied PFAS (which have ≤8 carbons) and that the migration of these compounds through this membrane could be described by Fick’s law of diffusion. When employed as the PRC, the isotopically labeled PFAS M2PFOA and M4PFOS were able to predict the mass transfer coefficients of the studied PFAS analytes. In contrast, the mass transfer coefficients were underpredicted by Br− and M3PFPeA. For validation, the PC-based passive samplers consisting of these four PRCs, as well as two other PRCs (M8PFOA and C8H17SO3−), were deployed in the sediment and water at a PFAS-impacted field site. The concentration–time profiles of the PRCs indicated that the samplers deployed in the sediment required at least 6 to 7 weeks to reach 90% equilibrium. If the deployment times are shorter (e.g., 2 to 4 weeks), PFAS concentrations at equilibrium could be estimated based on the concentrations of the PRCs remaining in the sampler at retrieval. All PFAS concentrations determined via this approach were within a factor of two compared to those measured in the mechanically extracted sediment pore water and surface water samples obtained adjacent to the sampler deployment locations. Neither biofouling of the rate-limiting barrier nor any physical change to it was observed on the sampler after retrieval. The passive sampler developed in this study could be a promising tool for the monitoring of PFAS in pore water and surface water.
Learn more about the journal: Environmental Science: Processes & Impacts
Learn more about Brent at: Brent G. Pautler | LinkedIn
Learn more about Alexander: Alexander Sweett | LinkedIn
Learn more about Jeff: Jeff Roberts | LinkedIn