Navigating the Challenges for the Analysis of PFAS

Navigating the Challenges for the Analysis of PFAS in Environmental Matrices to Meet TRRP Requirements Charles Neslund, Technical Director TCEQ Environmental Trade Fair, May 16 -17, 2017 Providing comprehensive scientific resources to environmental clients worldwide. www. Lancaster. Labs. Env. com

Polyfluorinated Compounds • Polyfluorinated Alkyl Substances (PFAS) are a class of compounds that have been in use since the late 1940’s, early 1950’s. • PFAS consists of both perfluorinated and polyfluorinated compounds • Perfluorinated – all carbons in the chain are fully bonded to fluorine • Polyfluorinated – not all carbons in the chain are only bonded to fluorine 2

Polyfluorinated Compounds PFAS compounds have been used in many applications. They have been used as additives in fluoropolymer production and as surfactants for numerous consumer applications; • • • Stain resistant coatings for furniture and carpeting Coatings for fast food wrappers and boxes Breathable waterproof fabrics Insecticides Lubricants Chromium Plating (mist suppression) 3

Polyfluorinated Compounds PFASs were also used in Aqueous Film Forming Foams (AFFF). Developed by 3 M and US Navy in the 1960’s. The low surface tension and positive spreading coefficient enabled film formation on top of lighter, less dense fuels. AFFF is a complex, proprietary mix that has been used in large volumes for decades; - Military - Oil and Gas Industry - Airports - Chemical Manufacturing - Fire Training Installations 4

Polyfluorinated Compounds • From mid-60’s to 1976, 3 M sole source supplier of AFFF • Ansul and National Foam became suppliers in 1976 • Since 1994, Angus, Chemguard and Fire Service Plus • Reality is multiple AFFFs used at most sites 5

Polyfluorinated Compounds However, out of these chemistries there are two compounds that have received the most attention; a. PFOA - was used as a surfactant in the manufacture of fluoropolymers – Du. Pont b. PFOS - was the principle component in Scotchgard and AFFF manufactured by 3 M – manufacture by 3 M has been discontinued since 2002 6

PFAS Perfluorooctanoic acid (also known as PFOA) MW = 414 amu BP = 189 -192 °C Density = 1. 8 grams/ml 7

PFAS Perfluorooctane sulfonic acid (also known as PFOS) MW = 500 amu BP = 133 °C at 6 torr 8

PFAS • The fluorine substitution gives this class of compounds unique characteristics • Contain a hydrophobic, fully fluorinated carbon chain • Also contains a hydrophilic functional group • Acids have low p. Ka’s and therefore at environmental p. Hs are soluble to moderately water soluble 9

Polyfluorinated Compounds There are several chemistries that are being looked at; • perfluorinated carboxylic acids • perfluorinated sulfonic acids/sulfonates • polyfluorinated telomer sulfonates • perfluorinated sulfonamides • fluorotelomer alcohols 10

Polyfluorinated Compounds Perfluorobutanoic acid Perfluoropentanoic acid Perfluorohexanoic acid Perfluorheptanoic acid Perfluorooctanoic acid Perfluorononanoic acid Perfluorodecanoic acid Perfluoroundecanoic acid Perfluorododecanoic acid Perfluorotridecanoic acid Perfluorotetradecanoic acid Perfluorohexadecanoic acid Perfluorobutanesulfonate Perfluorohexansulfonate Perfluoroheptanesulfonate Perfluorooctanesulfonate Perfluorodecanesulfonate Perfluorooctanesulfonomide Methylperfluoro-1 -octanesulfonamide Ethylperfluoro-1 -octanesulfonamide 4: 2 Fluorotelomer sulfonate 6: 2 Fluorotelomer sulfonate 8: 2 Fluorotelomer sulfonate 10: 2 Fluorotelomer sulfonate N-methylperfluoro-1 -octanesulfonamidoacetic acid N-ethylperfluoro-1 -octanesulfonamidoacetic acid 2 -(N-methylperfluoro-1 -octanesulfamido)-ethanol 2 -(N-ethylperfluoro-1 -octanesulfamido)-ethanol 11

Polyfluorinated Compounds • PFASs are generally chemically and biologically stable. Resist typical environmental degradation processes • PFASs bioaccumulate and by some estimates are present in blood serum of up to 98% of wildlife • PFOS added to Stockholm Convention list of Persistent Organic Pollutants • Growing library of toxicological and eco- toxicological studies so impacts are becoming better understood. Reference dose values for many compounds still an issue. 12

Advisory Limits • EPA Office of Water established Health Advisory Levels* PFOS = 0. 07 ug/l PFOA = 0. 07 ug/l • Minnesota one of few states with any regulatory action limits PFOS = 0. 3 ug/l PFOA = 0. 3 ug/l PFBS = 7 ug/l PFBA = 7 ug/l • New Jersey preliminary health based guidance** PFOS = 0. 2 ug/l PFNA = 0. 01 ug/l PFOA = 0. 04 ug/l (** 0. 014 ug/l) • Vermont Groundwater Enforcement Standard PFOS = 0. 02 ug/l PFOA = 0. 02 ug/l • EPA Region 4 levels in soils PFOS = 6 mg/kg PFOA = 16 mg/kg 13

Advisory Limits - Update * The U. S. Environmental Protection Agency (EPA) is issuing a lifetime drinking water Health Advisory (HA) for PFOA of 0. 07 micrograms per liter (μg/L) based on a reference dose (Rf. D) derived from a developmental toxicity study in mice; the critical effects included reduced ossification in proximal phalanges and accelerated puberty in male pups following exposure during gestation and lactation. EPA Document Number: 822 -R-16 -005 May 2016 The U. S. Environmental Protection Agency (EPA) is issuing a lifetime drinking water health advisory (HA) for PFOS of 0. 07 micrograms per liter (μg/L) based on a reference dose (Rf. D) derived from a developmental toxicity study in rats; the critical effect was decreased pup body weight following exposure during gestation and lactation. EPA Document Number: 822 -R-16 -004 May 2016 14

Tier 1 Groundwater PCLs Compound CAS # Conc ng/l Perfluorooctanoic sulfonic acid 1763 -23 -1 560 Perfluoroundecanoic acid 2058 -94 -8 290 Perfluoropentanoic acid 2706 -90 -3 93 Perfluorohexanoic acid 307 -24 -4 93 Perfluorododecanoic acid 307 -55 -1 290 Perfluorooctanoic acid 335 -67 -1 290 Perfluorodecanoic acid 335 -76 -2 370 Perfluorodecane sulfonic acid 335 -77 -3 290 Perfluorohexane sulfonic acid 355 -46 -4 93 Perfluorobutyric acid 375 -22 -4 71, 000 Perfluorobutane sulfonic acid 375 -73 -5 34, 000 Perfluoroheptanoic acid 375 -85 -9 560 Perfluorononanoic acid 375 -95 -1 290 Perfluorotetradecanoic acid 376 -06 -7 290 72629 -94 -8 290 754 -91 -6 290 Perfluorotridecanoic acid Perfluorooctane sulfonamide 15

Analytical Methodology There is only one EPA “sanctioned” method for the analysis of perfluorinated compounds – EPA Method 537, Version 1. 1 • Drinking water method – prescriptive list of compounds • Uses LC/MS/MS which is the analytical technique of choice • Has some limitations in the range of compounds that can be accommodated 16

Analytical Methodology • ISO Method 25101: 2009 often referenced, more amenable to surface water and wastewater • ASTM Methods D 7979 -15 addresses water and ASTM D 7968 -14 addresses sludges and soils but have not been subject to an EPA validation • No established method for soils, so often certify to lab SOP 17

Analytical Methodology • These methods are typically fit for the stated purpose, but may fall short as list of compounds and matrices increases. • In general, water methods use solid phase extraction (SPE) for the removal of PFASs from aqueous matrix • Soil methods involve extraction with solvent and/or water mix 18

Analytical Methodology • EPA Method 537 uses an SDVB solid phase extraction cartridge, which is adequate for the compounds listed. Falls short with additional compounds like the C 4 and C 5 acids. • EPA 537 uses 3 surrogate compounds and 3 internal standards. • Calibration is a typical internal standard calibration, which can be impacted by ion suppression observed with some matrices 19

UCMR 3 Unregulated Contaminant Monitoring Rule Perfluorinated Compounds (PFCs): EPA Method 537 included as UCMR 3 List 1 Contaminants; Compound Perfluorooctanesulfonic acid Perfluoroctanoic acid Perfluorononanoic acid Perfluorohexanesulfonic acid Perfluoroheptanoic acid Perfluorobutanesulfonic acid MRL ug/l 0. 04 0. 02 0. 03 0. 01 0. 09 20

UCMR 3 • Compounds are selected from the Contaminant Candidate List • Measures contaminants with no health standards under the Safe Drinking Water Act • Used to determine whether or not to regulate. Typically requires > 30 -40% detects • Focused on large water supplies (serving >10, 000 people) • Approximately 4% of UCMR 3 water samples had PFAS detections above MRLs 21

Analytical Methodology • ASTM D 7979 -15 avoids extraction by using direct injection • Use 9 isotopically labeled compounds as surrogates • Uses external standard calibration • Covers a much broader list of PFAS compounds – up to 21 • Reporting limits in the 5 ng/l to 25 ng/l range for most compounds 22

For Comparison… Water Reporting Limits LOQ (ng/L) Soil Reporting Limits LOQ (ng/g) Analyte Acronym Perfluorohexanoic acid PFHx. A 2 0. 4 Perfluoroheptanoic acid PFHp. A 2 0. 6 Perfluorooctanoic acid PFOA 2 0. 6 Perfluorononanoic acid PFNA 2 0. 4 Perfluorodecanoic acid PFDA 2 0. 4 Perfluoroundecanoic acid PFUn. DA 3 0. 6 Perfluorododecanoic acid PFDo. A 2 0. 6 Perfluorotridecanoic acid PFTr. DA 2 0. 6 Perfluorotetradecanoic acid PFTe. DA 2 0. 6 Perfluorobutanesulfonate PFBS 2 0. 6 Perfluorohexanesulfonate PFHx. S 2 0. 6 Perfluoro-octanesulfonate PFOS 6 0. 9 8: 2 fluorotelomersulfonate 8: 2 Ft. S 10 0. 9 23

Analytical Methodology • For our applications, we are tasked with a broader list of compounds and a wider range of matrices - Water/wastewater - soil/sediment - tissue • Use of weak anion exchange for extraction/clean-up • Incorporated the use of 18 isotopically labeled compounds as surrogates and isotope dilution quantitation 24

Instrumental Analysis

Analytical Methodology • Added in the use of several injection standards for monitoring and comparing instrument vs extraction performance • Target list of compounds increased to 27 “native” covered by 18 labeled compounds • As manufacturers provide more labeled analogs, will be a complete isotope dilution technique 26

Instrumental Analysis

Instrumental Analysis

Recent Updates EPA is releasing a document titled, “Technical Advisory-Laboratory Analysis of Drinking Water Samples for Perfluorooctanoic Acid (PFOA) Using EPA method 537 Rev 1. 1. ” This advisory describes a processes for laboratories to measure PFOA in a more comprehensive way. The improved technique allows laboratories to more consistently account for isomeric forms of PFOA (linear, the dominant form and branch-chained, the less common form) in the absence of a quantitative analytical standard that includes the various isomers. The approach described in the advisory is more inclusive and more protective. EPA therefore recommends that laboratories use the technique in future analysis.

Analytical Methodology • In response to this guidance document acquired technical grade standards of PFOS, PFOA and PFHx. S. • Technical grade standards run with initial calibrations as a qualitative indication of retention of branched isomers. • Branched summed with linear peak for calculation of PFAS content. 30

Analytical Methodology Total Ion Chromatogram of Technical Grade Standard 31

Analytical Methodology 32

Future At North American SETAC meeting in Orlando, FL in November of 2016, EPA indicated that they expect to release two draft methods for the analysis of PFAS compounds in non-potable water and soils/sediments by March of 2017. Update given in March that the process has been delayed and now estimate to be end of May 2017. 33

Future – TOP Analysis TOP – Total Oxidizable Precursors Based on paper authored by Erika Houtz and David Sedlak (ES&T, 2012, 46, 9342 -9349) Concept is to analyze a sample for perfluorinated acids and precursors (such as telomer sulfonates). Then subject a second aliquot of the sample to relatively harsh oxidative conditions. Analyze the oxidized sample for the same perfluorinated acids and precursors. Expect to see; a. Reduction or elimination of the precursors b. Increase in concentrations of perfluorinated acids 34

Summary • The emergence of contaminants like PFAS have increased the need and use of LC/MS/MS in the environmental lab • What “started out” as an analysis for PFOA and PFOS has rapidly grown to a more expanded list • As the list of analytes and matrices has expanded it has required labs to modify existing methodologies to achieve desired quality and performance • Delivery of the anticipated EPA methods could bring about the needed consistency 35

Questions 36