Document NaqvGapzVMpQQOD84ZvzbneR

FINAL June 13, 2023 RE: Technical Support Document in Response to ECHA Annex XV Restriction Proposal for PFAS, Gujarat Fluorochemical's RAC Comment Letter OVERALL COMMENT In response to the Annex XV Restriction Report, proposal for a restriction on per- and polyfluoroalkyl substances (PFAS), we offer the following comments. Overall, we find the proposal to be overly broad with respect to "PFAS", and scientifically distorted as it relates to fluoropolymers. The goal of reducing risks to the environment and human health from exposure to PFAS and/or their degradation products can be achieved without requiring a restriction on PFAS as single class - especially with PFAS having a broad range of chemical functional groups and physical/chemical properties. Furthermore, by essentially equating risk with persistence, the proposal significantly oversimplifies the approach to both hazard identification and risk assessment that has been central to risk management approaches under REACH and other EU regulatory frameworks for many years (see REACH Annex XIII). Fluoropolymers should be excluded from the proposed risk management option because they are not bioaccumulative, not mobile, and not toxic, and, therefore, do not pose a risk to the environment or human health. SPECIFIC COMMENTS 1. Persistence alone is not an appropriate measure of potential human health or environmental risk. Some PFAS have been described as persistent because they degrade or transform to "terminal" persistent compounds. As stated in the restriction proposal (p.24), "[t]he persistence as the core concern of PFASs has also been pointed out by scientists for instance in the Helsingr Statement on PFASs (Scheringer et al., 2014) as well as the follow up Madrid statement (Blum et al., 2015)." The proposal omits an important detail, which is that neither of these statements refer to fluoropolymers. Scheringer et al. (2014) specifically referred to non-polymer perfluoroalkyl acids (PFAS) - perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs), including perfluorooctanesulfonic acid (PFOS). Likewise, Blum et al. (2015) references scientific studies that are exclusively on non-polymer perfluoroalkyl acids (PFAAs), rather than fluoropolymers. As described in REACH Annex XIII, several regulatory frameworks in Europe require the assessment of "persistent, bioaccumulative, toxic" (PBT) properties of chemicals, including refined classifications such as "very persistent and very bioaccumulative (vPvB)". Substances with PBT/vPvB properties combine the characteristics of strong persistence with the potential to accumulate in the environment and biota (Moermond et al., 2012, p. 2). Dating back to the Stockholm Convention on Persistent Organic Pollutants, the objective for evaluating PBT as combined characteristics is the "protection FINAL of the environment and humans from substances that may harm these entities, either locally or globally, by accumulation in organisms where they then exert toxic effects" (Solomon et al., 2013, p. 1). Inherent in this objective is the understanding that the toxicity of a substance is contingent on the level present in the organism, and that chemicals with a lower bioaccumulation potential will present a lower risk. Persistence in the environment does not indicate that the substance would accumulate in organisms, nor that environmental levels would rise to such an extent that exposure would result in toxicity. According to ECHA, substances that persist for long periods of time in the environment and have a high potential to accumulate in biota are of specific concern because their long-term effects are rarely predictable1. Importantly, the PBT criteria established under REACH has always considered the characteristics of both persistency and bioaccumulation together, as indicators of potential risk (i.e., toxicity). Potential for bioaccumulation is defined by REACH criteria (EC-1907-2006) as the condition when the bioconcentration factor (BCF) in aquatic species is higher than 2000. PBT criteria have been applied consistently under numerous EU regulatory frameworks. The following are examples of applications of PBT concepts in regulatory programs over the past three decades (based on Table 3 from Moermond et al., 2012): Time Period Late 1990s 1998 2001 2003 2004 2006 Regulatory Program that Adopted or Applied PBT Concept Criteria Expert Group for Persistent Organic Pollutants develop criteria for categorization of POPs (Solomon et al. 2013) United Nations Economic Commission for Europe, the Convention on Long-range Transboundary Air Pollution (LRTAP) Stockholm Convention OSPAR Convention for the Protection of the Marine Environment of the Northeast Atlantic EU directives on Human & Veterinary Pharmaceuticals International Maritime Organization (IMO) International Convention for the Control and Management of Ship's Ballast Water and Sediments Registration, Evaluation, Authorisation and Restriction of Chemicals, (REACH) Across each of these regulatory frameworks, the combination of chemical properties that comprise PBT criteria are consistently evaluated: a. The chemical is evaluated for its persistence (P/vP) in the environment based on its half-life in environmental media (e.g., water, sediment, soil); and, b. The chemical is evaluated for bioaccumulation (B/vB) in biota based on its BCF, octanol/water coefficient (log KOW), or monitoring data; and, c. The chemical is evaluated for toxicity (T) to biota based on observed adverse effects at concentrations exceeding specific exposure thresholds, or evidence of 1 https://echa.europa.eu/understanding-pbt-assessment FINAL carcinogenicity, mutagenicity, reproductive toxicity, or specific target organ toxicity after repeated exposure. While there are differences in the specific criteria applied during PBT/vPvB evaluation, each regulatory framework makes clear that no standalone criteria, whether it be P/vP, B/vB, or T, is sufficient cause for PBT/vPvB status or environmental concern. In all cases, at least two of these three properties (P and B) must be established to identify a chemical as PBT/vPvB. In fact, there is precedent within EU chemical legislation for not restricting chemicals based on persistence alone. For example, vinyl neodecanoate was evaluated by the PBT Working Group and classified as "P/vP" but "not fulfilling PBT and vP/vB criteria". Specifically, the assessment report states that vinyl neodecanoate: "is not considered to be a PBT substance. It does not meet the B criteria and does not meet the screening criteria for T. It does meet the screening criteria for P (and vP)."2 2. Fluoropolymers are not bioaccumulative. Available data indicate that fluoropolymers are not bioaccumulative. Bioaccumulation potential is generally assessed based on a prediction using the octanol-water coefficient (e.g., log KOW > 3) or measurements in tissue and exposure media (e.g., BCF > 2000). Fluoropolymers such as polytetrafluoroethylene (PTFE, CASRN 9002-84-0), polyvinylidene fluoride (PVDF) homopolymer (CASRN 24937-79-9), perfluoroalkoxy alkane (PFA, CASRN 26655-00-5 and 31784-04-0), and fluoroelastomer (FKM, CASRNs 9011-17-0, 26424-79-6, and 25190-89-0) are insoluble in octanol and water (Henry et al., 2018; Korzeniowski et al., 2022). Therefore, the bioaccumulation potential of fluoropolymers cannot be reliably predicted from a log KOW. Measured biota tissue, water, and sediment concentrations indicate there is a low bioaccumulation potential for fluoropolymers in aquatic food webs. Researchers examining benthic invertebrate exposure to PTFE and other polymers demonstrated that there was no evidence of bioaccumulation through the aquatic benthic community from lower trophic level filterfeeders and grazers to higher trophic level omnivores and predators in the Arctic (Sfriso et al., 2020) and in Norway (Bour et al., 2018). 3. Fluoropolymers are not environmentally mobile. The restriction proposal argues that the continuous release of PFAS will lead to the accumulation of these compounds in the environment, such that unknown toxicity thresholds will be exceeded at some unknown point in the future. Moreover, the proposal also suggests that "PFAS" as a class will be found in all environmental media. Neither of these arguments apply to fluoropolymers. Fluoropolymers are not water soluble and will not likely result in widespread groundwater impacts or exposures from drinking water. If released to the environment, fluoropolymers are likely to remain in the environmental matrix they contact following release, such as terrestrial soil or aquatic sediment. Because fluoropolymers are chemically inert, they cannot partition and are not chemically mobile between water and soil/sediment. Any potential movement of fluoropolymers in the environment will occur via mechanical 2 https://echa.europa.eu/documents/10162/6af350f6-e259-4545-859f-293ce8515cb3 FINAL transport processes, such as overland flow from precipitation events (e.g., rainfall flows carrying fluoropolymers from soil to sediment via runoff). Indeed, Feng et al. (2022) recently demonstrated that PTFE in modelled tidal sediments showed enhanced retention and low likelihood of resuspension into the water column. Given their chemical inertness, non-volatility, and lack of water solubility, fluoropolymers are not highly mobile in the environment. 4. Fluoropolymers present in the environment are not toxic to humans or ecological receptors. Toxicity studies on fluoropolymers indicate that adverse effects are unlikely following exposure by human or ecological receptors to levels of fluoropolymer that may be present in the environment. A summary of available laboratory bioassays examining the toxicity of PTFE on test animals is provided by Radulovic and Wojcinski (2014). Given that fluoropolymers such as PTFE are insoluble in water and non-volatile, the most likely exposure route for PTFE is ingestion. In fact, acute oral toxicity of PTFE in rats is low, with a reported LD50 > 11,280 mg/kg. Researchers also found there were no observed adverse effects in rats exposed to up to 25% PTFE in rat diet for up to 90 days (Naftalovich et al., 2016; Radulovic & Wojcinski, 2014). The lack of toxicity of PTFE at 25% of the diet level fed to rats for 90 days was subsequently validated by peer review by the Scientific Review Panel of the Hazardous Substances Data Bank (TOXNET) (Naftalovich et al., 2016). Additionally, a four-week repeated dose study exposed mice to PTFE via their diet and reported no effects at any dose level, and no PTFE was detected in mice blood (Lee et al., 2022). The study supports an unbounded no-observed-adverse-effect-level (NOAEL) of 2,000 milligrams per kilogram (mg/kg) in mice, equivalent to approximately 9,720 mg/kg for a 60 kg human adult. The lack of toxicity from ingestion of PTFE and other fluoropolymers is attributed to their extremely high molecular weight, which renders absorption via the gastrointestinal tract negligible, and the fact that they are chemically inert compounds and not metabolized under physiological conditions (Naftalovich et al., 2016). Manufacturer Material Safety Data Sheets indicate that dermal contact with PTFE does not cause skin irritation in rabbits or humans. PTFE is not considered genotoxic and is so inert it has been used in genotoxicity protocols or test methodologies for Salmonella typhimurium mutagenicity testing of the US EPA Mobile Reaction Chamber (Naftalovich et al., 2016). The World Health Organization's International Agency for Research on Cancer concluded that organic polymeric materials (such as fluoropolymers) as a group are not classifiable as to their carcinogenicity to humans (Group 3) (IARC, 1999). 5. The "P-sufficient" approach is novel and precedent setting, worldwide. The Annex XV Restriction of all "PFAS" would be the first of its kind globally. The Restriction Report (p.24) references California EPA, Department of Toxic Substances and Chemicals (DTSC) as an example of established regulatory precedent, where a state regulatory agency has placed restrictions on all PFAS as class3. The referenced journal article (Blan et al., 2021) written by California DTSC staff specifically refers to PFAS present in specific consumer products. It would be inaccurate to conclude from this one example that 3 The Restriction report says: "It is noted that the first example of regulation of PFASs as a chemical class according to the P-sufficient approach has been introduced in California. Here a regulation of PFASs as a class is in place for certain consumer products under the California Safer Consumer Products Program (Balan et al., 2021)." FINAL California has adopted the P-sufficient concept as a PFAS risk management strategy. Indeed, an examination of recent legislative developments in California clearly shows that the state is actually pursuing a targeted risk management strategy: 1. PFAS in fire-fighting foam o Effective 1 January 2022, this legislation prohibits the use of class B firefighting foam containing intentionally added PFAS chemicals in California. 2. PFAS in textiles o Effective 1 January 2024, will prohibit the sale of PFAS-containing textile articles and require least toxic alternatives when replacing PFAS. 3. PFAS in cosmetics o Effective 1 January 2025, prohibits sale of cosmetic products that contain intentionally-added PFAS. 4. PFAS in plant-based food packaging and cookware o Effective 1 January 2023, prohibits sale of various plant fiber-based food packaging that contains PFAS. o Requires disclosure of certain chemicals, including PFAS, in cookware starting January 2023. Importantly, none of these legislative actions apply to industrial PFAS uses, where fluoropolymers are primarily utilized. Furthermore, these initiatives clearly demonstrate that California is pursuing targeted restrictions on PFAS used in specific consumer products. Moreover, Blan et al. (2021) inappropriately include fluoropolymers under their Psufficient approach based solely on one false statement and a second statement that lacks important context: 1. "Fluoropolymers are characterized by large molecular sizes and do not degrade to PFAAs under typical environmental conditions, although they have been observed to release [perfluorocarboxylic acids] PFCAs, including [perfluorooctanoate] PFOA, when heated to temperatures between 180 C and 800 C (Schlummer et al. 2015; Feng et al. 2015)." This statement, while correct regarding the large molecular weight of fluoropolymers, is incorrect with regard to the release of PFCAs such as PFOA. When heated to temperatures greater than 300 C, the potential transformation products of PTFE include trifluoroacetic acid (TFA, CASRN 76-05-1), hydrofluoric acid (CASRN 766439-3), tetrafluoroethylene (TFE, CASRN 116-14-3), hexafluoropropylene (CASRN 116-15-4), or perfluoroisobutylene (CASRN 382-21-8) (Ellis et al., 2001; Radulovic and Wojcinski, 2014; Henry et al., 2018; Tolkach et al., 2020). Heating PVDF homopolymer to temperatures greater than 300 C may result in the formation of hydrogen fluoride (HF, CAS No. 7664-39-3) and oxides of carbon (Arkema, 2011). Similarly, thermal decomposition of PFA at temperatures exceeding 300 C can produce HF, carbonyl difluoride (CASRN 353-50-4), carbon monoxide (CO, CASRN 630-08-0) and carbon dioxide (CASRN 124-38-9) (Inoflon Fluoropolymers, 2018). The potential transformation products of these fluoropolymers do not include PFCAs such as PFOA at intended use and end of life conditions. FINAL 2. "PFAAs are used in the manufacture of fluoropolymers and can occur as impurities in the final product." PFAAs such as fluorinated polymerization aids (FPAs), also referred to as fluorosurfactants, are currently used by some chemical manufacturers, albeit to a lesser extent, to facilitate the polymerization reaction that forms the final fluoropolymer product (Ameduri et al., 2023). PFOA and hexafluoropropylene oxide dimer acid (HFPO-DA, or GenX) are examples of these FPAs that have garnered widespread environmental concern. Furthermore, the substitution of non-fluorinated polymerization aids (NFPAs) for FPAs in the manufacture of the three main fluoropolymers by volume - PTFE, PVDF, and FKM - allows for the complete manufacture of these fluoropolymers without the use of FPAs and any resulting minor impurities (Ameduri et al., 2023). Therefore, by implementing the widespread use of NFPAs in fluoropolymer manufacturing, environmental contamination can be reduced to the maximum extent practicable. Residual impurities from non-polymeric PFAS entrained in the final fluoropolymer product, such as low molecular weight (<1000 Da) leachables and residual monomers, are quantifiably low: <1 ppm in PTFE and <50 ppb in PFA (Henry et al., 2018). This low leaching potential is what allows PTFE to meet the requirements for use in the food and beverage, pharmaceutical, medical, and semiconductor industries (Olabisi and Adewale, 2015). The following table summarizes the numerous regulatory safety standards that fluoropolymers meet for US and EU regulations, demonstrating their safety for use across drinking water, food contact, and medical industries: Regulation EC 10/2011 21CFR 177.1550 2011/65/EU USP Class VI 3-A 20-27 Umwelt Bundesamt (UBA) Regulatory Program Description EU Commission Regulation No 10/2011 of 14 January 2011 safety requirement on plastic materials and articles intended to come into contact with food (EU, 2011a). US food contact regulation for perfluorocarbon resins (CFR, 2023). Restriction of hazardous substances in electrical & electronic equipment (EU, 2011b). Biocompatibility testing requirements from the U.S. Pharmacopeia (USP). Includes safety standards for plastic, polymers, and elastomers to be applied in medical devices and surgical equipment. Testing includes acute systemic toxicity test, intracutaneous test, and implantation test (USP, n.d.). Sanitary standards for multiple-use plastic materials as a product contact or cleaning solution contact surfaces in equipment for production, processing, and handling of milk and milk products. Test criteria includes their ability to be cleaned, to receive effective bactericidal treatment, and to maintain their essential functional properties (3-A, 2011). German Environmental Agency (UBA) evaluation criteria for any plastic and rubber products that come in contact with drinking water (UBA, 2022). FINAL Sanitary Conformity Certification (ACS) Water Regulations Approval Scheme (WRAS) French mandatory certification for any device in contact with drinking water during production, treatment, storage, and distribution (ANSES, 2013; FR, n.d.). United Kingdom's accreditation body for approval process of water fittings. It aims to prevent the misuse, waste, excessive consumption, and inaccurate measurement of water and, ensure that drinking water is free from contamination. Includes products used only after the time of supply (WRAS, n.d.). References: 3-A Sanitary Standards (3-A). (2011). 3-A Sanitary Standards for Multiple-Use Plastic Materials, Number 20-27. Accessed May 2023. Ameduri, B., Sales, J., & Schlipf, M. (2023). Developments in fluoropolymer manufacturing technology to remove intentional use of PFAS as polymerization aids. International Chemical Regulatory and Law Review, 6(1). Arkema. (2011). Material Safety Data Sheet, Kynar Homopolymer. Blan, S. A., Mathrani, V. C., Guo, D. F., & Algazi, A. M. (2021). Regulating PFAS as a Chemical Class under the California Safer Consumer Products Program. Environmental Health Perspectives, 129(2), 025001. https://doi.org/10.1289/EHP7431 Blum, A., Balan, S. A., Scheringer, M., Trier, X., Goldenman, G., Cousins, I. T., Diamond, M., Fletcher, T., Higgins, C., Lindeman, A. E., Peaslee, G., de Voogt, P., Wang, Z., & Weber, R. (2015). The Madrid Statement on Poly- and Perfluoroalkyl Substances (PFASs). Environmental Health Perspectives, 123(5). https://doi.org/10.1289/ehp.1509934 Bour, A., Avio, C. G., Gorbi, S., Regoli, F., & Hylland, K. (2018). Presence of microplastics in benthic and epibenthic organisms: Influence of habitat, feeding mode and trophic level. Environmental Pollution, 243, 1217-1225. https://doi.org/10.1016/j.envpol.2018.09.115 FINAL Code de la Sant Publique [Public Health Code] (FR). (n.d.). Article R1321-48: Materials in contact with water. Last updated: 1 January 2023. Accessed May 2023. Available online at: https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000006909569 Ellis, D. A., Mabury, S. A., Martin, J. W., & Muir, D. C. G. (2001). Thermolysis of uoropolymers as a potential source of halogenated organic acids in the environment. 412. European Union (EU). (2011a). Commission Regulation (EU) No 10/2011 of 14 January 2011 on plastic materials and articles intended to come into contact with food (text with EEA relevance). Official Journal of the European Union. 14 January 2011. Accessed May 2023. Available online at: https://eur-lex.europa.eu/legalcontent/EN/ALL/?uri=celex%3A32011R0010 European Union (EU). (2011b). Directive 2011/65/EU of The European Parliament and Of The Council of 8 June 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment (recast). Official Journal of the European Union. 8 June 2011. Accessed May 2023. Available online at: https://eur-lex.europa.eu/legalcontent/en/TXT/?uri=CELEX:32011L0065 Feng, Q., Chen, Z., Greer, C. W., An, C., & Wang, Z. (2022). 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A., Montforts, M. H., Peijnenburg, W. J., Zweers, P. G., & Sijm, D. T. (2012). PBT assessment using the revised annex XIII of REACH: A comparison with other regulatory frameworks. Integrated Environmental Assessment and Management, 8(2), 359-371. https://doi.org/10.1002/ieam.1248 Naftalovich, R., Naftalovich, D., & Greenway, F. L. (2016). Polytetrafluoroethylene Ingestion as a Way to Increase Food Volume and Hence Satiety Without Increasing Calorie Content. Journal of Diabetes Science and Technology, 10(4), 971-976. https://doi.org/10.1177/1932296815626726 FINAL Radulovic, L. L., & Wojcinski, Z. W. (2014). Encylopedia of Toxicology; PTFE (Polytetrafluoroethylene; Teflon) (Vol. 3). Elsevier Inc. Scheringer, M., Trier, X., Cousins, I. T., de Voogt, P., Fletcher, T., Wang, Z., & Webster, T. F. (2014). Helsingr Statement on poly- and perfluorinated alkyl substances (PFASs). Chemosphere, 114, 337-339. https://doi.org/10.1016/j.chemosphere.2014.05.044 Sfriso, A. 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Annexes to evaluation criteria document for plastics and other organic materials in contact with drinking water (KTWBWGL) - Polymer-specific Part. Bad Elster, Germany. Accessed May 2023. Available online at: https://www.umweltbundesamt.de/sites/default/files/medien/3521/dokumente/polymersp ezifische_anlagen_der_bewertungsgrundlage_fur_kunststoffe_und_andere_organische_ materialien_en.pdf U.S. Code of Federal Regulations (CFR). (2023). Code of Federal Regulations Title 21, Volume 3, 21CFR177.1550: Title 21--Food and Drugs, Chapter I--Food and Drug FINAL Administration, Department of Health and Human Services, Subchapter B - Food for Human Consumption (Continued), Part 177 -- Indirect Food Additives: Polymers. Last Updated: 28 March 2023. Accessed May 2023. Available online at: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-177/subpart-B/section177.1550 U.S. Pharmacopeia (USP). (n.d.). Chapter 88: Biological Reactivity Tests, in Vivo. Accessed May 2023. 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