Development and Applications of Novel DGT Passive Samplers for Measuring 12 Per- and Polyfluoroalkyl Substances in Natural Waters and Wastewaters

Abstract

Extensive and long-term use of per-and polyfluoroalkyl substances (PFASs) has caused their widespread distribution in aquatic systems. A new diffusive gradients in thin-films (DGT) passive sampling method based on weak anion exchanger (WAX) binding layer is developed here for monitoring five perfluoroalkyl carboxylic acids (PFCAs), five perfluoroalkanesulfonic acids (PFSAs) and two PFASs (6:2 FTSA and GenX) in waters. Performance of WAX-DGTs was independent of environmental conditions, namely pH (3.03−8.96), ionic strength (1−500 mM), and DOM content (4−30 mg L −1 ). Diffusion coefficients (D) of the 12 PFASs in the diffusive gels were measured, 9 for the first time. Linear correlations between D and perfluoroalkyl chain lengths (CF 2 ) were established to obtain D for congener chemicals with the similar functional group and structure. The binding capacity of the WAX-DGT sampler was at least 440 μg PFASs per sampler, sufficient for applications in waters across a wide range of conditions and PFASs concentrations. Successful applications of WAX based DGT samplers in a wastewater treatment plant (WWTP) and three rivers has demonstrated that DGT is a powerful tool for monitoring, surveillance and research of these 12 PFASs in aquatic systems, and can be extended to wider suites of PFs in future.

Development and applications of diffusive gradients in thin films for monitoring pharmaceuticals in surface waters

“…Significant advantages of the DGT devices for monitoring organic pollutants were well-documented in previous studies ( Chen et al, 2013 ; Fang et al, 2021 ; Zheng et al, 2015 ). Compared with grab sampling, target analytes preconcentrated in DGT devices reduced matrix interference and improved the accuracy of analytical testing.…”

“…DGT has been applied to the measurement of a broad range of organic pollutants, including pesticides ( Guibal et al, 2017 ), pharmaceuticals ( Challis et al, 2018 ; Chen et al, 2012 ; Chen et al, 2013 ; Xie et al, 2018 ; Xie et al, 2021 ; You et al, 2020 ; You et al, 2019 ), household and personal care products ( Chen et al, 2017 ), synthetic musks ( Ren et al, 2020 ), perfluoroalkyl substances ( Fang et al, 2021 ; Guan et al, 2018 ), endocrine-disrupting chemicals ( Chen et al, 2018 ; Guo et al, 2017b ; Guo et al, 2019 ), illicit drugs ( Guo et al, 2017a ; Zhang et al, 2018 ), organophosphate esters ( Wang et al, 2019 ), brominated flame retardants ( Feng et al, 2019 ), bisphenols ( Zheng et al, 2015 ), bitter agent ( Liu et al, 2021a ), and melamine ( Liu et al, 2021b ). Although these pioneering studies extended the use of DGT to monitor organic chemicals, model contaminants have remained limited.…”

Effects of biofouling on the uptake of perfluorinated alkyl acids by organic-diffusive gradients in thin films passive samplers

“…18 The binding capacity of o-DGT with WAX sorbent for 12 PFAS was at least 40 μg per sampler. 29 Therefore, the sorption capacity of the o-DGT configuration used here is sufficient for typical sampling periods (2–4 weeks) in the field.…”

“…A wide range of dissolved organic matter concentrations (0–30 mg L −1 ) has been found not to affect o-DGT performance for some typical PFAS. 29 Therefore, the effect of dissolved organic matter was not considered in the present study. The lake water (pH = 7.6 ± 0.2) was collected one day before each renewal, and the water temperature was stabilized to 23 °C.…”

Studying the Application and Advances of Diffusive Gradients in-Thin Films Techniques (DGTs) to Constrain Mobility and Bioavailability of Heavy Metals in Soils

“…These includes: Chalex-100, ferrihydrate, Metsorb, zirconium dioxide (ZrO2), 3-mercaptopropyl functionalized silica, AG50W-X8 and XAD18. These DGT binding layers have been extensively evaluated with different materials in several researches for trace elements (Fang et al, 2021). This is done to determine whether these binding materials are capable of accumulating analysts of concern (Uptake).…”