Using Passive Samplers to Track per and Polyfluoroalkyl Substances (PFAS) Emissions From the Paper Industry: Laboratory Calibration and Field Verification

Abstract

Per and polyfluoroalkyl substances (PFAS) are becoming more stringently regulated and as such, a more diverse suite of environmental monitoring methods is needed. In this work a polar organic chemical integrative sampler (POCIS) with a nylon membrane and a combination of Oasis WAX and Fluoroflash® sorbents was calibrated in the laboratory and deployed in the field. A static renewal system was used to determine sampling rates for 12 PFAS which ranged between 0.69 ± 0.27 to 5.68 ± 1.80 L/day. POCIS devices were deployed for 10 days in lake Tyrifjorden, Norway which is known to be contaminated by a closed down factory producing paper products, in order to track the evolution of the PFAS contamination in a river system draining into the lake. Th sampling campaign enabled the stretch of the river which was responsible for the emissions of PFAS to lake Tyrifjorden to be identified. Freely dissolved concentrations determined with the POCIS were lowest at the site considered to reflect a diffuse PFAS contamination and highest at the site located downstream the factory. Perfluorooctanesulfonic acid (PFOS), perfluorohexanoic acid (PFHxA) and perfluorooctane sulfonamidoacetic acid (EtFOSAA) dominated the concentration profile at this site. Emissions of PFAS to lake Tyrifjorden were estimated to be 3.96 g/day for the sum of the 12 investigated PFAS.

Field Validation of a Novel Passive Sampler for Dissolved PFAS in Surface Waters

“…In a drinking‐water treatment plant, an average sampling rate of 45 ml day −1 was reported for the classic POCIS‐style sampler (Gobelius et al, 2019); correcting for the surface area (46 cm 2 ), the uptake rate was 0.98 ml day −1 cm −2 . Hale et al (2021) relied on a nylon mesh for the standard surface area (46 cm 2 ), and combined Oasis WAX with fluoroflash sorbent to obtain much greater uptake of 20–60 ml day −1 cm −2 . A modified POCIS sampler set‐up (smaller surface area, greater sorbent amount, and larger pore size in the polyethersulfone membrane than a traditional POCIS to maximize sampling rate) was used in an Australian study, and an uptake rate of 17 ml day −1 cm −2 was derived (270 ml day −1 over 16 cm 2 ; Kaserzon et al, 2012).…”

“…It incorporates a metal ring sandwiching a charged powdered adsorbent which binds the polar compound between two thin (100-200 µm) polyethersulfone membranes (Alvarez et al, 2004). However, the kinetic uptake and sampling rate of PFAS are dependent on the flow rate of the surrounding medium and the sorbent choice (Gobelius et al, 2019;Hale et al, 2021;Kaserzon et al, 2012Kaserzon et al, , 2014. Additional complications of the standard POCIS sampler include the potential of sorption to the polyethersulfone membrane (Endo et al, 2019).…”

A FAIR approach for detecting and sharing PFAS hot-spot areas and water systems

“…PFAS are detected in various environmental media, including drinking water [13], groundwater [14], surface water [15], wastewater treatment plants (WWTP) [16], soils [17], and air [18]. PFAS sources in the environment are associated with various sites, and unknown point sources around those sites [19][20][21][22][23][24][25].…”

Avoiding Artifacts in the Determination of Per- and Polyfluoroalkyl Substance Sorbent–Water Distribution

“…Some convenient methods of PFAS measurement in the environment are passive or grab sampling. − While passive- or grab-sampling methods for PFAS may vary, − a commonality of several is the use of an adsorbent resin binding phase to retain PFAS, either for the sampling itself (field preconcentration) or in later analysis (laboratory preconcentration, e.g., solid-phase extraction). For these purposes, an adsorbent with high affinity for a range of target compounds is usually preferable; though cost, binding mechanism, particle size, or contaminant selectivity may also be considered.…”