PFASsive™: A diffusion-based equilibrium passive sampler for sediment pore water and surface waters


Per- and Polyfluoroalkyl Substances (PFAS): PFAS are a large group of compounds found in aqueous film-forming foams, used for fire suppression and in everyday consumer products, and are made up of a chain of linked carbon and fluorine atoms. The length and branching of the carbon-fluorine chain varies between PFAS chemicals, but as the carbon-fluorine bond is strong, PFAS persist and have the potential to undergo long range transport in the environment. Until now, effectively monitoring and measuring PFAS at low, environmentally relevant concentrations in aquatic environments was difficult.

PFASsive™: A diffusion-based equilibrium passive sampler that has been developed and validated for targeted PFAS in sediment pore water and surface water. Upon retrieval, the water from PFASsive™ is treated as a water sample and the PFAS can be concentrated and measured using traditional EPA laboratory methods without the need for additional extraction steps required when sorbents are present. The result is a concentration (in ng/L). As the accumulation of PFAS into the sampler is based on molecular diffusion, the inclusion of a reverse tracer allows for the determination of the extent of equilibrium during the deployment and used to estimate the freely dissolved equilibrium concentration (Cfree) in the environment. Cfree has been shown to relate better to bioavailability, toxicity, and risk assessment models than conventional grab samples.

Experience the SiREM Difference: As is the case with SiREM’s other passive samplers (SP3™ and SPeeper™), PFASsive™ is offered as an end-to-end service where SiREM provides the samplers, optional support for diverless deployment, analytical chemistry (in partnership with Eurofins Environment Testing) and modelling of the final data to deliver the equilibrium concentration of PFAS. Overall, this sampler is easy to use, field evaluated and can be adapted to the growing list of PFAS chemicals of concern as both the regulations and analytical techniques evolve.


Anh Pham, Ph.D., Assistant Professor

Anh Pham is an Assistant Professor in the Department of Civil and Environmental Engineering. He obtained a B.S. degree in Chemical Engineering from Hanoi University of Technology (Vietnam), and M.S. and PhD degrees in Civil and Environmental Engineering from the University of California, Berkeley (USA). Prior to joining the University of Waterloo, Anh was an Assistant Professor in the Department of Civil and Environmental Engineering at Carleton University (Jan 2015- Dec 2018), and a Postdoctoral Associate at Duke University (2012 – 2014). His research group applies aquatic chemistry and geochemistry principles and employs analytical chemistry tools to investigate contaminant fate and transformation. The current research focuses on developing novel technologies for the remediation of contaminated soil and groundwater, treatment of various industrial waste streams including oil sands produced water, and removal of emerging contaminants.

Brent Pautler, Ph.D., Chemistry Services Manager

Brent received his Ph.D. in environmental analytical chemistry in 2013 where 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. His role includes managing and advancing SiREM’s passive sampling portfolio and analytical testing services while supporting Compound Specific Isotope Analysis (CSIA) business development.

More Information

Download information about PFASsive™: PFASsive™ Sampler for Per- and Polyfluoroalkyl Substances
For consultation regarding PFASsive™, contact Brent at