•Perfluorinated carboxylic acids – Significant adsorption seen with chain length 8 and greater. Glass filters show the best performance •Perluorinated sulfonic acids – Significant adsorption seen with chain length 6 or greater. Glass filters show the best performance •Fluorotelomer sulfonates – Only 8:2 FTS shows significant adsorption. 4:2 and 6:2 show little adsorption in matrices measured •Fluorinated phosphonates show very little adsorption, but phospinates show high levels of adsorption, and phosphate diesters •Glass filters show the best performance overall across all analyte and matrix types •AFFF samples show very severe losses for many compounds including PFOS on nylon filters. Use of glass filters results in good agreement with whole water tests •Concentration effects on adsorption were only observed in drinking water analyses, other matrices show no effect of concentration onamount of adsorption

1. Bharat Chandramouli, Coreen Hamilton, Jonathan Benskin, John Cosgrove, Axys Analytical Services, Sidney BC
The Interaction of Polyfluorinated Compounds with Filter Media: Implications for Phase Partitioning Studies
Discussion Acknowledgements
References
Conclusions
bharat@axys.com
Figure 2: Filter Types Studied
Figure1: Analytes of Interest
•Glass Fiber Filter – Sterlitech 0.5 µm porosity, 47 mm
•Teflon Laminated – Sterlitech 0.45 µm porosity , 47 mm
•Nylon- Nalgene filter assembly – 0.45 µm porosity 90 mm
•Polyethersulfone (PES) – Nalgene filter assembly – 0.45 µm
porosity 90 mm
•Polyfluorinated alkylated substances (PFAS) are anthropogenic chemicals of increasing concern due to their chain-length
dependent persistence and bioaccumulation potentials, adverse health effects in lab animals, and widespread
distribution in the global environment (Lindstrom et al., 2011)
•PFAS have different lifetimes and effects in the environment depending on whether they are present in aqueous/particle
phase. Separation of phases in the field/laboratory is therefore a critical step in the accurate analysis of PFAS (Houde et
al., 2011)
•There is emerging data that the sorption of PFAS on filter media can cause significant under-reporting of the PFAS in the
aqueous phase In filtered samples. (Labadie and Chevreuil 2011, Arp and Goss 2008)
•We studied the sorption of a suite of PFAS on a variety of filter media and investigated the role of compound type, chain
length, concentration, sample matrix and filter type on sorption behaviour.
Background and Objectives
Filter Sample (Different filter types)
Aqueous SPE Extraction with WAX Cartridge
Analyze by (-ESI) LC-MS/MS (three runs)
Extraction of Filter by mechanical shaker
Carbon, SPE WAX cleanup
Analyze by (-ESI) LC-MS/MS (three runs)
Method Summary
•Samples were extracted in batches of up to 18 samples which included 1 procedural blank and a spiked reference matrix sample (SPM). All samples
were spiked with isotopically-labeled internal standards prior to extraction and a recovery standard was added prior to analysis to assess matrix effects.
•Drinking water, surface water and effluent were spiked after filtering to eliminate effect of particulate matter on the experiments.
•Sample sizes ranged from 50- 500 mL and varied by analysis, sample matrix and expected sample levels
•Spiked sample analyses were carried out at multiple spike levels and all analyses were carried out in duplicate/triplicate except for some of the AFFF
affected aqueous samples
•Rinsates of filter equipment were analysed in some cases and eliminated as a source of adsorption
•Three separate analytical runs were utilized, one for the PFCAs, PFSAs and FOSAMs, one for the FTS, and one for the PAPs and PFPiA/PFPAs
Protocol Notes
Results
PAP and DiPAP
0.0 0.0 0.0 0.0
33.3
65.7
33.8
55.8
0
50
100
Glass Nylon Glass Nylon Glass Nylon Glass Nylon
Drinking
Water
Drinking
Water
Drinking
Water
Drinking
Water
6:2 PAP 8:2 PAP 6:2 diPAP 8:2 diPAP
PercentFilter
PFOA
0.3 1.4 0.0
15.7
0.5 1.2 0.0
9.5
0.9 1.7 0.0
17.6
4.1
11.6
0
50
100
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
Drinking Water Ambient POTW Effluent AFFF
PercentFilter
PFOS
2.4
27.6
4.2
95.1
7.0
24.3
30.0
86.7
7.8
23.0
18.1
80.4
10.2
93.9
0
50
100
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
Drinking Water Ambient POTW Effluent AFFF
PercentFilter
PFHxS
0.2
5.4
0.0
7.7
0.3
5.2 5.2 3.5 0.5 4.9 3.2 7.4 3.1
42.6
0
50
100
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
Drinking Water Ambient POTW Effluent AFFF
PercentFilter
PFDA
2.9
9.5
2.5
98.3
4.9 7.2 7.8
97.1
5.5 9.3 12.1
74.8
0
50
100
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Drinking Water Ambient POTW Effluent
PercentFilter
8:2 FTS
3.8
10.4 9.9
16.8
7.1
16.4
0
50
100
Glass Nylon Glass Nylon Glass Nylon
Drinking Water Ambient POTW Effluent
PercentFilter
PFOSA
3.0
23.3
32.4
86.8
1.5
7.5 3.5
94.1
3.2
17.2
3.5
88.3
0
50
100
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Glass
Nylon
PES
Teflon
Drinking Water Ambient POTW Effluent
PercentFilter
PFPiA
28.5
71.1
32.4
76.1
41.2
69.1
0
50
100
Glass Nylon Glass Nylon Glass Nylon
Drinking Water Drinking Water Drinking Water
6:6PFPiA 6:8PFPiA 8:8PFPiA
PercentFilter
•Perfluorinated carboxylic acids – Significant adsorption seen with chain length 8 and greater. Glass filters show the best performance
•Perluorinated sulfonic acids – Significant adsorption seen with chain length 6 or greater. Glass filters show the best performance
•Fluorotelomer sulfonates – Only 8:2 FTS shows significant adsorption. 4:2 and 6:2 show little adsorption in matrices measured
•Fluorinated phosphonates show very little adsorption, but phospinates show high levels of adsorption, and phosphate diesters
•Glass filters show the best performance overall across all analyte and matrix types
•AFFF samples show very severe losses for many compounds including PFOS on nylon filters. Use of glass filters results in good agreement
with whole water tests
•Concentration effects on adsorption were only observed in drinking water analyses, other matrices show no effect of concentration on
amount of adsorption
•Filtration of samples can have a significant effect on many fluorinated compounds and needs to be a
consideration in the sampling/analysis of fluorinated compounds.
•For most analytes including PFCAs and PFSAs, adsorption on the glass filters is within analytical error and is
appropriate for use in multiphase sample analyses.
•The use of filtration for phosphinic and phosphate ester compounds needs to be considered carefully as
significant losses are seen on all filter types
•Aqueous samples affected by AFFF application show high losses on certain filter types that can be
attributed to their surface activity/emulsion formation. The use of glass filters if necessary can reduce these
losses to within analytical error.
•Study of filter adsorption and similar analytical artefacts should be a part of method development
protocols
Figure 4: Effect of PFOS concentration in AFFF samples on filter
adsorption
Figure 3: Filter adsorption as measured by percent of analyte on filter by analyte, filter type and matrix
PFOS-Nylon Effect of concentration
0
20
40
0 100 200 300 400 500 600
Spiked Concentration (ng)
PercentFilter
Drinking Water
Ambient
POTW Effluent
PFOS - AFFF Effect of concentration
0
25
50
75
100
0 1000 2000 3000 4000 5000 6000
Total Concentration (ng)
PercentFilter
Glass Nylon
•Spiked drinking water
•Spiked ambient surface water
•Spiked POTW effluent
•Ground/surface water impacted by AFFF
Matrices Studied
•We thank the Jennifer Field research group at Oregon State University for their
collaboration on AFFF affected aqueous samples
•Lindstrom, A. B., Strynar, M. J. & Libelo, E. L. Environ. Sci. Technol. 45, 7954–7961
(2011)
•Houde, M., De Silva, A. O., Muir, D. C. G. & Letcher, R. J. Environ. Sci. Technol. 45, 7962–
7973 (2011).
•Labadie, P. & Chevreuil, M. Environmental Pollution 159, 3634–3639 (2011).
•Arp, H. P. H. & Goss, K.-U.. Atmospheric Environment 42, 6869–6872 (2008).
Experimental Protocol
Perfluoroalkyl acids (PFAAs)
19 congeners monitored
Perfluoroalkyl acid-precursors (PFAA-precursors)
8 congeners monitored
Perfluoroalkyl phosphonic/ phosphinic
acids
(PFPiAs/PFPAs)
6 congeners monitored
Perfluoroalkyl carboxylates (PFCAs)
9 congeners monitored
Perfluoroalkyl sulfonates (PFSAs)
3 congeners monitored
Fluorotelomer sulfonates
(FTSs; PFCA-precursors)
3 congeners monitored
Polyfluoroalkyl phosphate esters
(PAPs; PFCA-precursors)
4 congeners monitored
Perfluorooctane sulfonamides
(FOSAMs; PFOS-precursors)
1 congenor monitored
F F
F
F
F
O
O
-
n
F F
F
F
F
S O
-
O
O
n
R2
OHR1
O
P
O
O
6:2 PAP
8:2 PAP
6:2 diPAP
8:2 diPAP
n=3, PFBS
n=5, PFHxS
n=7, PFOS
R1=C2H4C6F13
R2=H
R1=C2H4C8F17
R2=H
R1=C2H4C6F13
R2=C2H4C6F13
R1=C2H4C8F17
R2=C2H4C8F17
n=3, 4:2 FTS
n=5, 6:2 FTS
n=7, 8:2 FTS
F F
F
F
F
S O
-
O
O
n
R1
R2 OH
P
O
PFHxPA
PFOPA
R1=OH
R2=C6F13
R1=OH
R2=C8F17
R1=OH
R2=C10F21
PFDPA
R1=C6F13
R2=C6F13
R1=C6F13
R2=C8F17
R1=C8F17
R2=C8F17
6:6 PFPiA6:6 PFPiA
6:8 PFPiA6:8 PFPiA
8:8 PFPiA8:8 PFPiA
n=2, PFBA; n=3, PFPeA; n=4, PFHxA;
n=5, PFHpA; n=6, PFOA; n=7, PFNA;
n=8, PFDA; n=9, PFUnA; n=10,
PFDoA
R2
R1
NS
O
O
F17C8
R1=H
R2=H
FOSA