Document 5bJNeQ3pBjVjYvebn5B8XpXm4

Information Document accompanying The Call for evidence supporting an analysis of restriction options for the PFAS group of substances (fluorinated substance(s)) I. Introduction The federal authorities of several member states, namely the Netherlands, Germany, Denmark, Sweden and Norway are planning to prepare an analysis of restriction options for the group of fluorinated substances subject to the description below (as defined under II.) since all these substances are considered to be persistent (see under III.) constituting an unacceptable risk to the environment and human health. This call for evidence is intended to generate further information for the evaluation of the most appropriate restriction measures, as well as the scope in terms of substance identity, uses and conditions for restriction option(s) to be taken forward in the development of an Annex XV Dossier. II. Proposal for the definition of PFAS considered to be in scope of the restriction As indicated by the name, per- and polyfluoroalkyl substances (PFASs) comprise a group of organic substances containing alkyl groups on which all or many of the hydrogen atoms have been replaced with fluorine as structural fragments. The most well-known PFASs contain fully fluorinated carbon chains (= alkyl chains) of various chain lengths attached to a functional group, like carboxylic or sulfonic acids. Examples include the eight-carbon long PFOA or PFBS with four fully fluorinated carbon atoms in chain. PFASs with only one perfluorinated carbon atom, like trifluoroacetic acid (TFA, CF3CO2H), carry the smallest possible structural unit required for a substance to be grouped in this class. In the later years, novel PFAS structures have been developed wherein new structure elements have been introduced, like other halogens (-Cl or -Br) or ether elements (-O-). Some of these PFASs contain no CF3-elements as there are other groups at the end of the alkyl chains, while they may contain several -CF2-units within their chemical structures. In any case, PFAS substances are persistent in the environment (resistant to degradation). Substances with a non-fluorinated part in addition to their PFAS-elements often degrade until they reach persistent PFAS degradation products. Hence, as the scope of the current Call for Evidence has been selected: Substances that contain at least one aliphatic -CF2- or -CF3 element. The scope may be represented by the general structure formulas in Figure 1. Commented [A1]: The original wording " All fluorinated substances that contain 1 or more C atoms on which all the H substituents have been replaced by F atoms, in such a manner that they contain at least one aliphatic perfluorocarbon moiety such as -CnF2n- are considered to be proposed to be in the scope of a restriction proposal." is a complicated way of saying "all substances containing at least one aliphatic -CF2- element." It is suggested to include also the -CF3 element in order to ease the task for the reader although this could be argued to be included in -CF2-. F F C F F C R n F CF3(CF2)nR F F R' C C R'' n F F R'CF2(CF2)nR'' Figure 1. General structure formulas representing the scope of PFAS relevant for this Call for Evidence. R, R', R'' = any chemical group, n 0. All substances covered by the scope are considered to contribute to the concentrations of persistent PFASs in the environment. The length of the fluorinated alkyl chains in the structures in Figure 1 may be in the range one carbon atom and upwards (linear or branched), while the groups R, R' and R'' may be any chemical groups or any combinations thereof, resulting in a large number of PFAS substances covered. Polymeric substances are also within the scope as long as they fulfil the indicated structure formulas, both backbone fluorinated and side-chain fluorinated polymers. There are currently more than 4700 different PFAS substances on the market, and new PFASs are continuously developed. Due to the common feature of being persistent, all PFAS sub-groups are covered by the present investigation. Listed below are examples from a nonexhaustive list of substances and substance groups that are included. Non-exhaustive list of substances and substance groups: In the following, selected subgroups of PFASs are explained and exemplified. It is in general difficult to define non-ambiguous sub-categories for the whole class of PFASs due to their inherent complexity. Some PFAS substances may therefore belong to several of the groups indicated. The list below is a non-exhaustive list of PFASs and should be regarded as a help for the reader to understand the scope of the current investigation. R, R' and R'' In the following, the groups R, R' and R'' may represent any chemical group or any combination thereof, including (but not limited to) hydrogen, linear and branched alkyl, olefinic, aromatic, alcohols (-OH), amines (-NH2), halogens (F, Cl, Br, I), esters (-CO2R), ethers (-O-), thiols (-SH), carboxylic acids (-CO2H), sulfonic acids (-SO3H), sulfinic acids (-SO2H), sulfones (-SO2R), phosphonic acids (-PO(OH)2), phosphinic acids (-PO(OH)), as well as their derivatives, including salt forms and polymers. Perfluoroalkyl substances Commented [A2]: The drawings could even be substituted with: F F F C R F R' C R'' F CF3R R'CF2R'' The extra (CF2)n-units were included to indicate that the PFAS often are in chains, n may be 0. Commented [A3]: The definition of the different R's was repeated many times, so it is proposed as an alternative to include a definition once up-front. Aliphatic substances for which all hydrogen atoms attached to carbon in the corresponding non-fluorinated substance have been replaced by fluorine atoms: 1. Perfluoroalkanes, linear and branched; CnF2n+2; n1 Examples: F FF F CF 3 F F F3C CF 2 CF 2 CF CF 3 F F F F F F CAS No. 355-04-4 2. Perfluorinated cycloalkanes; CnF2n; n3 Examples: F F F F CF 2 CF 2 CF 2 F F F F F F F F F F FF CAS No. 335-27-3 3. Aliphatic perfluoroalkyl substances, linear or branched; CnF2n+1-R, R-CnF2n-R'; n1; R, R' as defined above Examples: F FF F O F S F OH F F F O PFBS F3C CF 2 CF 2 CF 2 CF 2 CF 2 CF 2 PFOA O OH F3C O CF 2 P CF 2 CF 2 OH CF 2 CF 2 CF 2 CF 3 CAS No. 52299-25-9 This category includes many of the most well-known PFASs and subcategories, like carboxylic acids (PFCAs, e.g. TFA, PFBA, PFHxA, PFOA), sulfonic acids (PFSAs, e.g. triflic acid, PFBS, PFHxS, PFOS), sulfinic acids (-SO2H), phosphonic acids (-PO(OH)2), phosphinic acids (-PO(OH)), etc. Substances with more than one functional group attached to the perfluoroalkyl chain are also included. 4. Perfluorinated cyclic aliphatic substances; CnF2n-1-R, R-CnF2n-2-R'; n3; R, R' as defined above Example: CF 2 CF 2 CF SO 3 H F3C CF CF 2 CF 2 CF 2 Cyclic PFOS This category includes in principle the same range of functionalities as the previous group. The only difference being that the perfluoroalkyl groups contains a cyclic structure. 5. Aliphatic perfluoroalkyl ethers, linear or branched, saturated or unsaturated; R-CnF2n-O-CmF2m-R'; n, m 1; R, R' as defined above Examples: F3C CF 2 O CF 2 CF 3 CAS No. 358-21-4 F3C CF 2 O CF 2 - CO 2 CF + NH 4 CF 3 HFPO-DA (GenX) This category includes the full range of functionalities, including side-chain and backbone fluorinated polymers and polymers with perfluoroalkylether backbones. 6. Perfluoroalkyl amines; N(CnF2n+1)(CmF2m+1)(CxF2x+1); n, m, x 1 Example: CF 3 CF 2 CF 2 N CF 2 CF 2 CF 2 CF 3 F3C CF 2 Perfluamine, (CF3CF2CF2)3N, CAS No. 338-83-0 Commented [A4]: Substance registered at 1000-10.000 tonnes per year. Acute Tox. 3 or 4. Used as blood substitute. Not covered by any WP. Polyfluoroalkyl substances Substances containing at least one aliphatic group wherein several but not all of the hydrogen atoms attached to carbon have been replaced by fluorine in such a way that they carry at least one -CF2- or CF3 element. 7. Aliphatic polyfluorinated substances, linear or branched, cyclic, saturated or unsaturated; R-CnF2n-R' or R-CnF2n-xHx-R'; n, x 1; R, R' as defined above Examples: F3C H2 CF 2 CF 2 C OH CF 2 CF 2 CF 2 C H2 6 : 2 fluorotelomeralcohol (FTOH) O F3C CF CF 2 CF CF 2 CF 3 CF 3 Semi-fluorinated alkane, CAS No. 297730-93-9 - O F F FF F O F H + N N S F O F FF FF F 6 : 2 FTS derivative used in fire-fighting foam, CAS No. 80475-32-7 F F3C CH2 Hydrofluoroolefin, HFO-1234yf, CAS No. 754-12-1 F F F F F F F Hydrofluorocarbon, CAS No. 15290-77-4 F H F H F F Norflurane (INN), a hydrofluorocarbon, CAS No. 811-97-2 This category includes a broad range of different substances. It is similar to group 3 above, but in addition to the per- or polyfluoroalkyl units, the substances may also contain non-fluorinated fragments. In principle, about any possible chemical group can be attached to a perfluoroalkyl chain. This category includes e.g. fluorotelomer substances (n : 1 and n : 2) and their derivatives, semi-fluorinated alkyl substances, hydrofluorocarbons and hydrofluoroolefins (used in refrigerants), substances with perfluoroalkyl groups attached to aromatics, PFCA- and PFSA-derivatives (usually prepared via the corresponding alkanoyl fluoride or sulfonyl fluoride substances), and side-chain fluorinated polymers, etc. 8. Aliphatic polyfluorinated ethers, linear or branched, saturated or unsaturated; RCnF2n-xHx-O-CmF2m-yHy-R'; m, n, x, y 1; R, R' as defined above Examples: F FF FF FF F O - O Cl S + K O O F F F FF F F F F F FF FH F O F - F O O O F F F F + NH 4 F-53B, CAS No. 73606-19-6 ADONA This category includes some of the more novel PFAS substances developed to replace substances like PFOA and PFOS. However, the new alternatives also tend to be persistent or degrade to persistent PFASs in the environment. 9. Hydrofluoroethers; R-CnF2n-O-CmH2m-R'; n, m 1; R, R' as defined above, including side-chain fluorinated polymers 10. Side-chain perfluorinated aromatics; CnN2n+1-(aromatic rings(s)) 11. Fluoroalkenes; -CF=CF- 12. Fluoropolymers, polymers with a poly- or perfluorinated backbone Example: F FF FF F Cl F Cl F Cl F F FF FF F Polytetrafluoroethylene, PTFE F FF FF F Poly(chlorotrifluoroethylene), PCTFE This category includes a range of different polymers prepared from different monomers or mixtures of monomers, including homopolymers from the following monomers: CF2=CF2 (PTFE); CF2=CH2 (PVDF); CF2=CFCl (PCTFE); and co-polymers from the following monomer combinations: CF2=CF2 + CF2=CF-O-CnF2n+1 (PFA); CF2=CF2 + CF2=CF-CF3 (FEP); CF2=CF2 + CH2=CH2 (ETFE); CF2=CF2 + CF2=CF-CF3 + CF2=CH2 (THV), etc. Perfluoropolyethers (PFPEs) with a polymer backbone of repeating units of CnF2n-O-CmF2m- are included in this group. 13. Side-chain fluorinated polymers Example: Commented [A5]: The CAS no listed as example in the original document is not an ether, but an olefin. Do you have any other examples from this group? This seems to be a special case of the previous group. One can even use the previous general formula with the right selection of n and m. Hence, this group could be left out if we do not have any particularly important group members. Commented [A6]: Not sure if these substances need a separate group. Maybe they could be part of group 7? I could not find the structure of CAS No 89790-02-9 that you listed as example. Maybe you can help me with it? Commented [A7]: Not part of scope which is at least one CF2- or -CF3. F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F F O O O O O O O O The side-chain fluorinated polymers include a range of different polymers based on standard polymer chemistry with different per- or polyfluorinated side-chains attached to the polymer backbone. Examples include acrylate based polymer backbones with fluorotelomer side-chains (like above) and similar solutions based on urethane linkages of the side-chains to the backbone.