PFOS, PFOA and Other Fluorinated Compounds: Sampling and Analy<cal Challenges

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1 PFOS, PFOA and Other Fluorinated Compounds: Overcoming Sampling and Analy<cal Challenges Author: Date: Terry Obal, Ph.D., C.Chem. RPIC Federal Contaminated Sites Na?onal Workshop April 14-16, 2014

2 Acknowledgments Adam Robinson Sin Chii Chia 2 maxxam.ca

3 Outline Overview Physical/Chemical Proper?es Nomenclature Environmental Significance Sampling, Analy?cal and Repor?ng Considera?ons Sampling Challenges Analy?cal Methods Understanding the results 3 maxxam.ca

4 What are they? Perfluorooctanoic Acid (PFOA) Hydrophobic Perfluorooctane Sulfonate (PFOS) Hydrophilic Teflon Scotchguard 4 maxxam.ca

5 Chemical and Physical Proper?es Very stable and persistent do not degrade Low vola?lity Soluble in water Readily bind (sorb) to variety of materials (hard to predict par??oning) Bioaccumula?on Ubiquitous ( they re everywhere ) 5 maxxam.ca

6 Fluoropolymers vs. Fluorinated Telomers Fluoropolymers Long chain molecules Fire resistant Repel oil, grease, stains and water Used to provide non- s?ck surface in cookware and waterproof breathable membranes for clothing Hundreds of other uses in virtually all industry segments (e.g. aerospace, automo?ve, chemical, electronics, tex?le, etc.) Fluorinated Telomers Surfactants and surface treatment chemicals in many products (e.g. repellent coa?ngs on tex?les, leather and paper) High performance surfactants in products that need to flow evenly (e.g. paints, coa?ngs, fire figh?ng foams, engineering coa?ngs in the manufacture of semi- conductor coa?ngs) 6 maxxam.ca

7 PFC Naming Conven?ons Perfluorobutanoic Acid aka Perfluorobutyric Acid Perfluorobutanoate 7 maxxam.ca

8 Naming Conven?ons Abbrevia<on Acid Conjugate PFBA Perfluorobutanoic Acid Perfluorobutanoate PFBS Perfluorobutanesulfonic Acid Perfluorobutanesulfonate PFPA Perfluoropentanoic Acid Perfluoropentanoate PFHxA Perfluorohexanoic Acid Perfluorohexanoate PFHxS Perfluorohexanesulfonic Acid Perfluorohexanesulfonate PFHpA Perfluoroheptanoic Acid Perfluoroheptanoate PFOA Perfluorooctanoic Acid Perfluorooctanoate PFOS Perfluorooctanesulfonic Acid Perfluorooctanesulfonate PFNA Perfluorononanoic Acid Perfluorononanoate PFDA Perfluorodecanoic Acid Perfluorodecanoate PFDS Perfluorodecanesulfonic Acid Perfluorodecanesulfonate PFUdA Perfluoroundecanoic Acid Perfluoroundecanoate PFDoA Perfluorododecanoic Acid Perfluorododecanoate PFTrDA Perfluorotridecanoic Acid Perfluorotridecanoate PFTeDA Perfluorotetradecanoic Acid Perfluorotetradecanoate PFOSA Perfluorooctanesulfonamide Perfluorooctanesulfonamide 8 maxxam.ca

9 Environmental Pathways for PFC Exposure Commercially used perfluorinated compounds (PFCs) have been widely detected in humans, but the sources of human exposure are not fully characterized Suggested sources of exposure Drinking Water Dust/Ambient Air Food 9 maxxam.ca

10 Where are they being found? Although PFOS, PFOA and other PFCs are likely to be found anywhere, at differing concentra?ons Typical areas where these may be compounds of concern, at elevated concentra?ons, are: AFFFs: Airports Run- off from incidents of fire Landfill leachate WWTP Effluent 10 maxxam.ca

11 and now they re making the news 11 maxxam.ca

12 Toxicology S?ll being evaluated - a range of toxicological effects have been reported in a variety of species Readily absorbed and accumulates in all?ssues, especially target organs (e.g. liver) Not metabolized and eliminated slowly Studies suggest high poten?al human toxicity Not yet confirmed as human carcinogen PFOS exposure has been associated with many health problems including some cancers 12 maxxam.ca

13 Regulatory Status in Canada (PFOS Focus) Risk management strategies should maintain environmental PFOS concentra?ons as low as possible by: Preven?ng re- introduc?on to market; and Addressing remaining uses through restric?ons/exemp?on May 30, 2012: AFFFs with PFOS >0.5 ppm are prohibited (certain military opera?ons may be excluded) January 2013: Environment Canada consulta?on document issued describing current risk management ac?ons in Canada and globally May 29, 2013: Manufacture, use, sale and import of PFOS and PFOS- containing products is prohibited in Canada (Note: Other PFCs, e.g. polyfluorotelomer sulphonates, are used in newer AFFF formula?ons) 13 maxxam.ca

14 Regulatory Status 2010/2015 PFOA Stewardship Program: Eight (8) global suppliers agree to: 95% reduc?on in PFOA (and related precursor) levels in emissions rela?ve to 2000 levels Total elimina?on of PFOA (and related precursor) levels in emissions September 30, 2013 USEPA Significant New Use Rule (SNUR) rela?ng to perfluoroalkyl sulphonates (PFASs) SNUR related to perfluoroalkyl carboxylates (PFACs) (in- process) 14 maxxam.ca

15 Regulatory Limits Drinking Water Jurisdic<on PFOA (ug/l) PFOS (ug/l) PFBA (ug/l) PFBS (ug/l) Canada Health Canada N/V N/V U.S.A - EPA N/V N/V U.S.A. Minnesota U.S.A. New Jersey 0.04 N/V N/V N/V U.S.A. North Carolina 2 N/V N/V N/V Europe United Kingdom N/V N/V Europe - Germany 0.1 (PFOA and PFOS) N/V N/V 15 maxxam.ca

16 Regulatory Limits UCMR3 Compound Minimum Repor<ng Level (ug/l) Perfluorooctane sulphonate (PFOS) 0.04 Perfluorooctanoic Acid (PFOA) 0.02 Perfluorononanoic Acid (PFNA) 0.02 Perfluorohexanesulfonate (PFHxS) 0.03 Perfluoroheptanoic Acid (PFHpA) 0.01 Perfluorobutane sulphonate (PFBS) maxxam.ca

17 Provisional Soil Levels - PFOS Jurisdic<on Residen<al (ug/g) Commercial (ug/g) Industrial (ug/g) Canada Health Canada U.S.A EPA Region IV 6 N/V N/V 1) CCME Guidelines for PFOS an<cipated 2014/ maxxam.ca

18 Problem Statement(s) Inconsistent approaches to analysis for PFCs in simple and complex environmental matrices High risk of sample cross contamina?on due to ubiquitous nature of PFCs and the tendency to be found at high concentra?ons Sample matrices range from simple to complex Data comparability between laboratories is difficult High variability Lack of confidence in the results Inability to make supportable remedial decisions 18 maxxam.ca

19 Sampling, Analy?cal and Repor?ng Considera?ons 19 maxxam.ca

20 Sample Containers Teflon? 20 maxxam.ca

21 Sampling Sampling and field quality assurance plans must address the potenial for cross contamina?on and/or false posi?ves Consider poten?al sources of PFOS, PFOA and other PFCs: Teflon Gore- tex Water proof field note books Water for blanks MUST be PFC free. 21 maxxam.ca

22 Analy?cal Methods The Basics 22 maxxam.ca

23 Importance of Isotope Dilu?on If the isotopically labeled analogue is added to the sample at the very beginning of the analy?cal process (i.e. before any sample homogeniza?on, extrac?on, clean- up etc.), it enables exact compensa?on for variances at all stages of the analysis, from sample prepara?on through to the final instrumental measurement. IDMS provides greater accuracy than other calibra?on methods because it compensates for any matrix effects that may suppress recovery of the parameters being measured. 23 maxxam.ca

24 Importance of Isotope Dilu?on Simply put the recovery of the labeled compound, which is not naturally present in the sample, is an exact representa?on of the recovery of the na?ve compound which is present in the sample. Using PFOS as an example, the 13 C 4 - labelled analog of PFOS is used to correct for varying recovery of the na?ve ( 12 C) PFOS from the sample. So if the recovery of the labeled PFOS is 60%, the recovery of the na?ve PFOS being measured will also be 60%. 24 maxxam.ca

25 Branched (technical) vs. Linear PFOS When interpre?ng PFOS data, it is important to understand if it is being quan?fied as the linear or branched chain isomers Technical PFOS is a mixture of linear and branched chain PFOS isomers Linear PFOS is typically pure Branched chained PFOS contains at least 3 isomers This is an important differen?a?on because if linear PFOS is used as the calibra?on standard, the quan?ta?ve results on real- world samples (containing a mix of linear and branched PFOS) can be off by as much as 40% 25 maxxam.ca

26 Limits of Quan?ta?on (LOQs) Compound Water (ug/l) 26 Perfluorooctanesulfonamide (PFOSA) maxxam.ca LOQs Soil (ug/kg) Perfluorobutanoic Acid (PFBA) Perfluorobutanesulfonic Acid (PFBS) Perfluoropentanoic Acid (PFPA) Perfluorohexanoic Acid (PFHxA) Perfluorohexanesulfonic Acid (PFHxS) Perfluoroheptanoic Acid (PFHpA) Perfluorooctanoic Acid (PFOA) Perfluorooctanesulfonate (PFOS) Perfluorononanoic Acid (PFNA) Perfluorodecanoic Acid (PFDA) Perfluorodecanesulfonate (PFDS) Perfluoroundecanoic Acid (PFUdA) Perfluorododecanoic Acid (PFDoA) Perfluorotridecanoic Acid (PFTrDA) Perfluorotetradecanoic Acid (PFTeDA)

27 Sampling Protocols and Analy?cal Methods: Key Areas for Considera?on Sample Collec?on Protocols: Low flow, bailers, passive samplers Cross- contamina?on Minimize exposure of samples/extracts to poten?al sources of PFCs Fill containers completely Minimize transfer of sample aliquots (i.e. as much as is possible, avoid subsampling prior to addressing adsorp?on) Sample Prepara?on: Homogeniza?on/Filtra?on 27 maxxam.ca

28 Sampling Protocols and Analy?cal Methods: Key Areas for Considera?on Sample Extrac?on/Clean- up Direct injec?on/solid phase extrac?on (SPE) Analysis: Isotope Dilu?on LC/MS/MS Calibra?on: solvent based standards/matrix matched standards Data Reduc?on: Linear vs branched chain PFOS 28 maxxam.ca

29 What to expect when reques?ng analyses Laboratory Accredita?on (ISO Guide 17025): SCC (Canada) DoD (USA) Calibra?on Range: Water: ug/l Soil: ug/kg Standard Turnaround Time 10 working days Rush Analyses Minimum 3 days 29 maxxam.ca

30 Ques?ons? 30 maxxam.ca