PFAS POLY- AND PERFLUOROALKYL SUBSTANCES

Size: px

Start display at page:

Download "PFAS POLY- AND PERFLUOROALKYL SUBSTANCES"

Raymond York
5 years ago
Views:

June 217 THE EMERGING ISSUE PFAS POLY- AND PERFLUOROALKYL SUBSTANCES Big

2 Contents Introduction Chemistry Products / Sources Toxicology / Exposure / Risk Regulatory Evolution Site Conceptual Model Investigation Challenges / Advanced Analytical Solutions Summary Arcadis 216 Property of Arcadis, all rights reserved

PFAS Introduction PFAS comprises many thousands of compounds multiple sources Advanced analytical methods are being adopted to measure PFAS PFAS are impacting drinking water worldwide None of the

3 PFAS Introduction PFAS comprises many thousands of compounds multiple sources Advanced analytical methods are being adopted to measure PFAS PFAS are impacting drinking water worldwide None of the PFASs biodegrade, some biotransform to daughter compounds that are extremely persistent Some PFAS are classed as persistent organic pollutants Dramatically increasing regulatory concern Arcadis 217 3

4 USES Where We Find Them and How They ve Evolved CONSUMER FFF ELECTROPLATING AEROSPACE MANUFACTURING BY-PRODUCTS

Multiple and Varied PFAS Uses Examples of Common Uses:

Foams (FFFP) Electroplating mist suppressants Semiconductor

Hydraulic fluids Consumer Products Oil and water resistant

Polishes, Adhesives, Lubricants, Inks, Waxes Fast-food

5 Multiple and Varied PFAS Uses Examples of Common Uses: Fluorosurfactant Firefighting foams for Class B (liquid hydrocarbon) fires e.g. Aqueous Film Forming Foams (AFFF), Film Forming Fluoroprotein Foams (FFFP) Electroplating mist suppressants Semiconductor manufacture Pesticides Insecticides and Herbicides Aviation Hydraulic fluids Consumer Products Oil and water resistant finishes on paper, textiles, carpeting, cookware Dyes, Polishes, Adhesives, Lubricants, Inks, Waxes Fast-food packaging Cleaning agents detergents, carpet cleaners Shampoos and Handcreams Arcadis 216 Property of Arcadis, all rights reserved

6 PFAS Sources Firefighting Foams Metal Plating Textiles Electronics Photography Paper Coatings Paints Hydraulic Fluids Arcadis 216

Potential Sources Defence Sites Refineries Large

Biosolids land application Coatings / Textiles

7 Potential Sources Defence Sites Refineries Large Rail Yards Chem Facilities Commercial and some private airports Landfills Fire Stations Municipal Fire Training Areas Plating Facilities Biosolids land application Coatings / Textiles manufacturers Performance Plastics Manufacturers Arcadis 216

Summary Points on PFASs in Paper PFAS mainly used in food contact paper meant to contain greasy substances Concentrations of PFAS in the materials range between.

8 Summary Points on PFASs in Paper PFAS mainly used in food contact paper meant to contain greasy substances Concentrations of PFAS in the materials range between.1 mg/kg to ~1 mg/kg Paper cups not a major source of PFAS (i.e., coffee cups) Fast food wrappers are a major sources of PFAS in food contact materials; also popcorn bags and papers designed for greasy baked items; paper tableware (excluding cups) also likely to contain PFAS Long chain PFAS are still very common in China Plenty of proprietary replacements to PFAS that advertise as being fluorine free are available Other paper applications such as corrosion inhibition paper may contain PFAS, but food contact material contains highest concentrations From Schaider et al. 217 Arcadis 216

Class B Fire Fighting Foams Fires involving liquid hydrocarbons are class B and extinguished with

Fluoroprotein Foam (FFFP) AFFF s were develop in 196 s and have been used widely to extinguish class B

9 Class B Fire Fighting Foams Fires involving liquid hydrocarbons are class B and extinguished with fluorosurfactant foams such as: o aqueous film forming foams (AFFF) o Fluoroprotein (FP) o Film Forming Fluoroprotein Foam (FFFP) AFFF s were develop in 196 s and have been used widely to extinguish class B (liquid hydrocarbon) fires PFAS foam composition is chemically complex with multiple organofluorine compounds many of which are not detected by commercially available analytical methods (i.e. precursors or polyfluorinated compounds) PFAS foams contains both polyfluorinated and perfluorinated compounds Arcadis 216 Property of Arcadis, all rights reserved

10 PFAS Foams being Replaced C8 (PFOS and PFOA) phased-out C8 replaced with compounds with shorter (e.g., C4, C6) perfluorinated chains C4, C6 PFAS are less bioaccumulative, still extremely persistent and more mobile in aquifer systems vs C8 - more difficult and expensive to treat in water. Solutions for characterizing all PFAS species important to cover current and future risks / liabilities Regulations addressing multiple chain length PFAS (long and short) are evolving globally Fluorine free (F3) foams contain no persistent pollutants F3 foams pass ICAO tests with highest ratings for extinguishment times and burn-back resistance, so are widely available as replacements to AFFF Manufacturer F3 Foam National Foam Jetfoam (Aviaton) National Foam Respondol (Class B) Auxquimia UNIPOL Vsfocum Silvara Bioex Ecopol Fomtec Enviro 3x3 Plus Solberg Re-healing Foam RF6 / RF3 Dr. Sthamer Moussol F-F3/6 Non-fluorinated replacement foams are being increasingly adopted Arcadis 216

PFAS PROPERTIES AND CHEMISTRY Parameter PFOS (Giesy, 21; OECD, 22) PFOA (EFSA, 28) CAS number 1763-23-1

11 PFAS PROPERTIES AND CHEMISTRY Parameter PFOS (Giesy, 21; OECD, 22) PFOA (EFSA, 28) CAS number Chemical formula C 7 H 15 COOH Molar weight 538,23 g/mol 414,7 g/mol Boiling point n.a C

PFAS - Properties and Implications PFAS plumes are generally longer as PFAS are generally: Highly soluble Low K OC Recalcitrant extreme persistence Mostly Anionic Chemical Properties PCB (Arochlor

12 PFAS - Properties and Implications PFAS plumes are generally longer as PFAS are generally: Highly soluble Low K OC Recalcitrant extreme persistence Mostly Anionic Chemical Properties PCB (Arochlor 126) PFOA PFOS TCE Benzene Molecular Weight Solubility (@ C), mg/l Vapor Pressure (@25 C), 4.5x x mmhg Henry s Constant, atmm 4.6x x x /mol Log Koc Arcadis 216 Property of Arcadis, all rights reserved October 18,

Perfluorinated compounds (PFCs) Perfluorinated Compounds (PFCs) generally are the Perfluoroalkyl acids (PFAAs) PFAAs include: Perfluoralkyl carboxylates (PFCAs) e.g. PFOA Perfluoroalkyl sulfonates (PFSAs) e.

13 Perfluorinated compounds (PFCs) Perfluorinated Compounds (PFCs) generally are the Perfluoroalkyl acids (PFAAs) PFAAs include: Perfluoralkyl carboxylates (PFCAs) e.g. PFOA Perfluoroalkyl sulfonates (PFSAs) e.g. PFOS Perfluoroalkyl phosphinic acids (PFPiS); perfluoroalkyl phosphonic acids (PFPAs) There are many PFAAs with differing chain lengths, PFOS and PFOA have 8 carbons (C8) - octanoates C1 Methane C2 Ethane C3 Propane C4 Butane C5 Pentane C6 Hexane C7 Heptane C8 Octane C9 Nonane C1 Decane C11 Unodecane C12 Dodecane C13 Tridecane C14 Tetradecane PFAAs totally resist biodegradation & biotransformation so are extremely persistent Arcadis 216 Property of Arcadis, all rights reserved July

14 Polyfluorinated Compounds -Precursors Thousands of polyfluorinated precursors to PFAAs have been commercially synthesized for bulk products The common feature of the precursors is that they will biotransform to make PFAA s as persistent dead end daughter products PFAS do not biodegrade i.e. mineralise Some precursors are fluorotelomers Some are cationic (positively charged) or zwitterionic (mixed charges) this influences their fate and transport in the environment Cationic / zwitterionic PFAS tend to be less mobile than anionic PFAAs and so can potentially be retained longer in source zones Environmental fate and transport will be complex as PFAS comprise multiple chain lengths and charges PFOA Arcadis 216 Property of Arcadis, all rights reserved

15 Arcadis 216

17 Arcadis 216 October 18,

18 Aerobic Biotransformation Funnel Precursors converted to PFAAs Arcadis 216

REGULATORY CLIMATE / PFAS DISTRIBUTION Evolution of regulatory

20 Human Exposure to PFAS Drinking water Food Main exposure House dust Indoor air Outdoor air Consumer products Fluoropolymers inc. side chain polymers Fluorosurfactants Performance chemicals Product residuals Precursor PFAA Arcadis 216 Property of Arcadis, all rights reserved

21 PFAS Exposure, Distribution, and Elimination in Humans EXPOSURE DISTRIBUTION ELIMINATION Most exposure is likely from ingestion of contaminated food or water Exposure can also comes from: Breast milk Air Dust (especially for children) Skin contact with various consumer products PFAS bind to proteins, not to fats. Highest concentrations are found in blood, liver, kidneys, lung, spleen and bone marrow. Long chain PFAS such as PFOS, PFHxS and PFOA have bioaccumulative properties. Shorter chain PFAS generally have a lower bioaccumulation potential, although there may be some exceptions. Elimination of PFOS, PFHxS and PFOA from the human body takes some years, whereas elimination of shorter chain PFAS are in the range of days Apart from chain length, blood halflives of PFAS are also dependent on gender, PFAS-structure (branched vs. straight isomers), PFAS-type (sulfonates vs. carboxylates) and species. Elimination mainly by urine. Arcadis 216 Property of Arcadis, all rights reserved

Toxicity for Humans Exposure mainly by ingestion PFAS bind to proteins (not to lipids / fats) and are mainly detected in blood, liver and kidneys PFOS: carcinogenity suggestive (US EPA, 214).

22 Toxicity for Humans Exposure mainly by ingestion PFAS bind to proteins (not to lipids / fats) and are mainly detected in blood, liver and kidneys PFOS: carcinogenity suggestive (US EPA, 214). PFOA: possibly carcinogenic (International Agency for Research on Cancer, IARC, 214) Study with 656 children demonstrated elevated exposure to PFOS & PFOA are associated with reduced humoral immune response [1] Large epidemiological study of 69, persons found probable link between elevated PFOA blood levels and the following diseases: high cholesterol, ulcerative colitis, thyroid disease, testicular cancer, kidney cancer and preeclampsia C8 science panel [2] European Food Safety Authority (28) established a TDI for PFOS and PFOA of 15 ng/kg bw/day and 1.5 ng/kg bw/day USEPA has selected a Reference Dose for PFOS and PFOA of 2 ng/kg bw/day (May 216) [1] Arcadis 216 [2]

23 Perfluorinated Compounds: Reproductive Toxicity Pregnant/breastfeeding mothers are the primary sensitive populations. Detected in breastmilk, umbilical cord blood, and amniotic fluid At birth infants have roughly equivalent serum levels as mothers. Levels in infants increases further after birth from breast milk or from water in formulae Study of PFOA exposure in mice during pregnancy (Lau et al. 26) Chronic toxicity study in rats, PFOA (Butenhoff et al 212) Hepatic mitochondrial alteration in mice following prenatal exposure to PFOA (Quist et al. 215) Mammary gland sensitivity in mice (Tucker et al. 215) Skeletal Variations Testicular Cancer Persistent Liver Effects Mammary Gland Development NOAEL USEPA dismissed, New Jersey DWQI included (14ppt target for PFOA) USEPA Determine Safe Levels for Humans Arcadis 216

24 Evolving Regulatory PFAS Values Overview Drinking, Surface and Ground Water (mg/l) US EPA (Drinking Water) (.7) PFOS O=8 PFOA O=8 PFBS B=4 PFBA B=4 PFPeA/S PFHxA CANADA (Drinking Water) Pe=5 Hx=6.6.2 MINNESOTA (Drinking Water) VERMONT (Drinking Water) NEW JERSEY TEXAS-Residential.1 ground drinking (Groundwater) COMPOUND REGULATED AND CHAIN LENGTH KEY (.2) PFHxS PFHpA Hx=6 Hp=7 PFOSA O=8 PFNA N=9 PFDA D=1 PENNSYLVANIA (Drinking Water -proposed) drinking.5.5 DENMARK (Drinking & Groundwater) UK (Drinking Water) 1 5 (.1) THE NETHERLANDS FEDERAL GERMANY (Drinking Water) (.1) (.9).23 ground drinking.53 ITALY (Drinking Water) (.5).3 (.5).5.5 (.5).5 (.5) (.5) (.5) SWEDEN (Drinking Water) European Surface Waters (PFOS).65 STATE OF BADEN- WÜRTTEMBERG (Groundwater).3/.3/ (1).3/.3/ 1/.23/(.3).3/ 3/ 7/ 3/ AUSTRALIA (Drinking Water) (.7) (.7).56 Australian Surface Waters (PFOS).23 Arcadis 216 PROPERTY OF ARCADIS, ALL RIGHTS RESERVED

PFAS in European Surface Waters River PFOS (ng/l) Flow(m 3 /s) Scheldt (Be, NL) 154 - Seine (Fr) 97 8 Severn

25 PFAS in European Surface Waters River PFOS (ng/l) Flow(m 3 /s) Scheldt (Be, NL) Seine (Fr) 97 8 Severn (UK) Rhine (Ge) 32 1,17 Krka (Sl) 1,371 5 Property of Arcadis, all rights reserved Arcadis 216 July

International Regulations http://chm.pops.

30 Arcadis 215 1/18/217 3

31 PFAS in US Public Water Supplies USEPA UMCR 3, May 216 Detected in ~ 2% of large public water supplies Arcadis 216 October 18,

32 Arcadis 216 PFAS News 216

34 ANALYTICAL TOOLS

35 Sampling Considerations Detection limits are low (ng/l) so avoid use of fluorinated polymers which can release PFAS (e.g. Teflon) in sampling / analytical methodologies Avoid use of glass sampling vessels or metals as PFAS adhere to the surface of glass/metals Samples should be collected in polypropylene or polyethylene (HDPE) bottles fitted with an unlined (no Teflon), polypropylene screw cap. Avoid any filtering during sample preparation as PFAS adhere to filter matrices PFAS stratify in solution as they collect at the air / water interface so consider that: sampling from groundwater wells should ideally be from the surface of the water table (AFCEC protocols) protocols for working with water samples must include a vigorous shake of the solution before subsampling Micro-organisms can degrade precursor molecules making more PFAA s Arcadis 215 Specific specialist sampling protocols required

36 Analysis by LCMSMS via EPA Method 537 or similar US EPA Method 537: Analysis for selected PFAS in drinking water 12 PFAAs and 2 Precursors: PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUA, PFDoA, PFTrA, PFTeA PFBS, PFHxS, PFOS N-EtFOSAA, N-MeFOSAA Method 537 has been adapted with more analytes to other media Up to 65 individual analytes (laboratory dependent) Groundwater with PFAS LODs ranging as low as.9 ng/l Availability of standards and other factors limit the number of PFAS that can be measured with a single method Thousands of precursors and their transient metabolites makes synthesis of a comprehensive set of standards unrealistic Conventional analysis will not reflect total PFAS mass Arcadis 216 Property of Arcadis, all rights reserved

Advanced Analytical Techniques Expanding analytical tool box to assess total PFAS Arcadis 216 Total oxidizable precursor (TOP) Assay Initial LC-MS/MS analysis with re-analysis following oxidative

37 Advanced Analytical Techniques Expanding analytical tool box to assess total PFAS Arcadis 216 Total oxidizable precursor (TOP) Assay Initial LC-MS/MS analysis with re-analysis following oxidative digest Detection limits to ~ 2 ng/l (ppt) Commercially available in UK, Australia, under development in US Particle-induced gamma emission (PIGE) Spectroscopy Isolates organofluorine compounds on solid phase extraction, measures total fluorine Detection limits to ~ 15 ug/l ( ppb) F Commercially available in US Adsorbable organofluorine (AOF) Isolates organofluorine compounds with activated carbon and measures F by combustion ion chromatography Detection limits to ~ 1 ug/l (ppb) F Commercially available in Germany, Australia Time of Flight MS (LCQTOF) MS Identifies multiple precursors via mass ions capture and accurate mass estimation (to.1 of a Dalton) to give empirical formulae (e.g. C 1 F 21 O 3 N 2 H 4 ) Useful Graphics 18 October Property of Arcadis, all rights reserved

Total Oxidizeable Precursor Assay (TOP) Oxidation of Precursors to PFAAs with OH PFSA Precursors OH PFCA Precursors R OH + shorter PFAA products PFPA OH + Precursors 8 OH 8 85 o C 8

38 Total Oxidizeable Precursor Assay (TOP) Oxidation of Precursors to PFAAs with OH PFSA Precursors OH PFCA Precursors R OH + shorter PFAA products PFPA OH + Precursors 8 OH 8 85 o C 8 Heat S 2 O SO 4 - Dilute Sample ph >12 NaOH + K 2 S 2 O 8 OH- ph>11 SO OH Approach described in Houtz and Sedlak, ES&T, 212 Arcadis 216 Property of Arcadis, all rights reserved

39 Total Oxidizable Precursor (TOP) Assay Fire Training Area Soil Composite Groundwater Composite 75% increase 24% increase Arcadis 216 EPA Method 537 Underestimates the PFAS Mass

Digest AFFF precursors and measure the hidden mass: TOP

PFOS / PFOA) from PFAS (PFAA precursors) over 2+ years

form PFAAs Too many PFAS compounds and precursors so

precursors to PFAA s Indirectly measure precursors as a

fail to measure the hidden PFAS precursor mass, the TOP

40 Digest AFFF precursors and measure the hidden mass: TOP Assay Microbes slowly make simpler PFAA s (e.g. PFOS / PFOA) from PFAS (PFAA precursors) over 2+ years Need to determine precursor concentrations as they will form PFAAs Too many PFAS compounds and precursors so very expensive analysis Oxidative digest convert PFAA precursors to PFAA s Indirectly measure precursors as a result of the increased PFAAs formed Analytical tools fail to measure the hidden PFAS precursor mass, the TOP assay solves this Arcadis 216 Property of Arcadis, all rights reserved

41 Arcadis 215 October 18,

43 Conceptual Site Model

org/wp- content/uploads/216/9/rolland-weber-pfos-

44 Excessive Costs October 18, content/uploads/216/9/rolland-weber-pfos- PFAS-German-activities-Final.pdf Arcadis 217 Risk based approaches not adopted in Germany 44

45 Conceptual Site Model Arcadis 215

46 Groundwater Risks to Receptors Landfill Leachate Municipal / Domestic WWTP Industry & Manufacturing Agricultural Land Commercial / Domestic Products Metal Plating ASTs Fuel storage (FFFP / FP) AFFF / FFFP / FP Fire training Incident Response Arcadis 215??? Diffuse Ground level impacts and ground/surface water Source Pathway Receptor High concentration, spill site, route via groundwater to receptor e.g. drinking water well Grasshopper effect via widening of source zones e.g. concentrated plume intercepts crop spray irrigation to make secondary wider source area for more dilute plume

47 Arcadis 216 October 18,

PFAS Source Zones, a CSM AFFF/FFFP/FP F F C n F C 8F17 S N H N + H3C H C F 8 17 CH S C1H9 CH Source Zone - Hidden Cationic and Zwitterionic Precursors Less mobile as bound via ion exchange to

48 PFAS Source Zones, a CSM AFFF/FFFP/FP F F C n F C 8F17 S N H N + H3C H C F 8 17 CH S C1H9 CH Source Zone - Hidden Cationic and Zwitterionic Precursors Less mobile as bound via ion exchange to negatively charged fine grain soils (e.g. silts & clays). Precursor biotransformation is limited by the anaerobic redox conditions created by the co-occuring hydrocarbons. Hydrocarbon NAPL Short hydrocarbon plume Direction of groundwater flow Anionic precursor biotransformation increases as aerobic conditions develop CH CH H N NH + F S F C F n CH C 6F13 H 3C F F C F F S N C 4H9 N + H CH 3 CH 3 CH 3 Hidden anionic mobile PFAA precursors C8 C7 C6 C4 C5 C3? C2? F F C F n H N S CH N H 3C H 3C C 5F11 C4H9 C6F17 - S C 4H9 CH H 3C C F 8 17 S C 4H 9 H 3C C8F17 S CH 3 C 8F1 7 C 4H 9 S C F 8 17 S C 6F1 3 CH 3 S C 8F1 7 C8F1 7 S S C8F1 7 C 6F1 3 S S C8F1 7 Anionic PFAA dead end daughters 6F13 S C 6F1 3 S C S C8 C7 C6 C4 C5 C3? C2? Increasing mobility of shorter perfluoroalkyl chain PFAS -3mV -2mV REDOX ZONATION -1mV mv 1mV 2mV Property of Arcadis, all rights reserved

TOP assay Develop intelligent CSM Use of detailed site specific

50 Summary - PFAS Management.. Better site characterisation Assess contaminants comprehensively TOP assay Develop intelligent CSM Use of detailed site specific quantitative risk assessment Consider more sustainable risk management solutions Address public risk perception Arcadis 215

51 Arcadis 215 1/18/217 51

52 Ask Us About These New Resources! Download at: ns/558/4/environmental-fate-andeffects-of-poly-and-perfluoroalkylsubstances-pfas-report-no-8-16 Arcadis 217 Property of Arcadis, all rights reserved October 18,

Andrew H. Thalheimer, P. Eng., Indra K. Kalinovich, PhD, EIT, C.Chem Dillon Consulting Limited

Andrew H. Thalheimer, P. Eng., Indra K. Kalinovich, PhD, EIT, C.Chem Dillon Consulting Limited = Per- and Polyfluorinated Alkyl Substances Perfluorinated-carbon tail hydrophobic interactions Functional