Indirect precursors to perfluorooctanesulfonate (PFOS): Environment tier II assessment

8 March 2019

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CAS Registry Numbers: 31506-32-8, 1691-99-2, 24448-09-7, 40630-61-3, 376-14-7, 423-82-5, 127133-66-8, 594864-11-6, 68298-62-4, 68329-56-6, 68555-90-8, 68555-91-9, 68555-92-0, 68568-77-4, 68797-76-2, 68867-60-7, 68909-15-9, 70776-36-2, 92265-81-1, 68227-96-3, 68298-78-2, 68299-39-8, 68586-14-1, 68867-62-9, 70900-40-2, 68081-83-4, 94313-84-5, 2991-51-7, 161074-58-4, 185630-90-4, 253682-96-1, 91081-99-1, 192662-29-6, 68649-26-3, 68608-14-0, 68608-13-9, 306973-47-7, 306975-56-4, 3820-83-5, 2250-98-8, 30381-98-7, 67969-69-1, 29117-08-6, 37338-48-0, 68958-61-2, 1652-63-7, 38006-74-5, 67939-88-2, 68298-11-3, 94133-90-1, 57589-85-2, 68891-96-3, 75260-69-4, 94133-91-2, 944578-05-6

Preface

This assessment was carried out by staff of the National Industrial Chemicals Notification and Assessment Scheme (NICNAS) using the Inventory Multi-tiered Assessment and Prioritisation (IMAP) framework.

The IMAP framework addresses the human health and environmental impacts of previously unassessed industrial chemicals listed on the Australian Inventory of Chemical Substances (the Inventory).

The framework was developed with significant input from stakeholders and provides a more rapid, flexible and transparent approach for the assessment of chemicals listed on the Inventory.

Stage One of the implementation of this framework, which lasted four years from 1 July 2012, examined 3000 chemicals meeting characteristics identified by stakeholders as needing priority assessment. This included chemicals for which NICNAS already held exposure information, chemicals identified as a concern or for which regulatory action had been taken overseas, and chemicals detected in international studies analysing chemicals present in babies’ umbilical cord blood.

Stage Two of IMAP began in July 2016. We are continuing to assess chemicals on the Inventory, including chemicals identified as a concern for which action has been taken overseas and chemicals that can be rapidly identified and assessed by using Stage One information. We are also continuing to publish information for chemicals on the Inventory that pose a low risk to human health or the environment or both. This work provides efficiencies and enables us to identify higher risk chemicals requiring assessment.

The IMAP framework is a science and risk-based model designed to align the assessment effort with the human health and environmental impacts of chemicals. It has three tiers of assessment, with the assessment effort increasing with each tier. The Tier I assessment is a high throughput approach using tabulated electronic data. The Tier II assessment is an evaluation of risk on a substance-by-substance or chemical category-by-category basis. Tier III assessments are conducted to address specific concerns that could not be resolved during the Tier II assessment.

These assessments are carried out by staff employed by the Australian Government Department of Health and the Australian Government Department of the Environment and Energy. The human health and environment risk assessments are conducted and published separately, using information available at the time, and may be undertaken at different tiers.

This chemical or group of chemicals are being assessed at Tier II because the Tier I assessment indicated that it needed further investigation.

For more detail on this program please visit: www.nicnas.gov.au.

Disclaimer

NICNAS has made every effort to assure the quality of information available in this report. However, before relying on it for a specific purpose, users should obtain advice relevant to their particular circumstances. This report has been prepared by NICNAS using a range of sources, including information from databases maintained by third parties, which include data supplied by industry. NICNAS has not verified and cannot guarantee the correctness of all information obtained from those databases. Reproduction or further distribution of this information may be subject to copyright protection. Use of this information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner. NICNAS does not take any responsibility whatsoever for any copyright or other infringements that may be caused by using this information.

Acronyms & Abbreviations

Grouping Rationale

This Tier II assessment considers the environmental risks associated with the industrial uses of a group of 55 chemicals. The chemicals in this group are structurally related compounds in that they all contain a chain of eight perfluorinated carbons linked to a terminal sulfonamide or sulfonic ester group.

NICNAS has developed an action plan to assess and manage chemicals which may degrade to perfluorinated carboxylic acids, perfluoroalkyl sulfonates and similar chemicals (NICNAS, 2018a). The primary assumption outlined in this action plan is that chemicals with a perfluorinated chain terminated by a sulfonyl group will degrade to the perfluoroalkyl sulfonate. On this basis the chemicals in this group are each considered to have the potential to degrade into the environmentally hazardous perfluorooctanesulfonate anion (PFOS).

Perfluorooctanesulfonic acid, perfluorooctanesulfonates, perfluorooctanesulfonamides and perfluorooctanesulfonyls are listed on Annex III of the Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade (the Rotterdam Convention). In addition, perfluorooctanesulfonic acid and certain PFOS-related substances have recently been identified as Persistent Organic Pollutants (POPs) under Annex B of the Stockholm Convention on Persistent Organic Pollutants (the Stockholm Convention). Further information on PFOS can be found in the Environment Tier II Assessment of the Direct Precursors to Perfluorooctanesulfonate (PFOS) group (NICNAS, 2015a).

The degradation of PFOS is very slow compared with its rate of formation from degradation of the precursors and PFOS will be the final degradant from multiple precursors. Therefore, the amount of PFOS in the environment (general or local) is expected to be higher than that of any of the precursors. It will therefore be assumed for the purposes of this assessment that the primary risk posed by the chemicals in this group results from the release of PFOS to the environment. The IMAP-Environment Tier II assessment for Direct Precursors to Perfluorooctanesulfonate (PFOS) (NICNAS, 2015a) has been used as a reference assessment.

Chemical Identity

In this assessment, "PFOS" is used to denote the conjugate base anion of perfluorooctanesulfonic acid (i.e. the perfluorooctanesulfonate anion). However, it is noted that this descriptor is commonly used in relation to a range of substances which may easily form the anion in water, such as the parent acid and salts of the acid.

Acronyms for certain chemicals in this group have been taken from a list of recommended acronyms and other terminology recently compiled to facilitate clear and unambiguous communication regarding the major classes of industrially important perfluoroalkyl and polyfluoroalkyl substances (Buck, et al., 2011).

This assessment includes a range of neutral and ionic organic chemicals, polymers, telomers, and chemicals that are in the category of unknown or variable composition, complex reaction products or biological materials (UVCBs). The chemicals in this assessment have been sub-grouped based on similar structural properties below for presentation purposes.

Structural information is presented where it is available. For polymers and telomers, constituent monomers are presented. Due to the typically variable size and structure of polymer molecules, the molecular formula and molecular weight for these substances are not presented.

Where insufficient structural information is available, the CAS RN and chemical name are presented only.

Neutral Organic Derivatives of Perfluorooctanesulfonamides

CAS RN

31506-32-8

Chemical Name

1-Octanesulfonamide, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N-methyl-

Synonyms

MeFOSA

N-methylperfluorooctanesulfonamide

Structural Formula

31506328.jpg

Molecular Formula

C9H4F17NO2S

Molecular Weight (g/mol)

513.17

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)NC

CAS RN

1691-99-2

Chemical Name

1-Octanesulfonamide, N-ethyl-1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N-(2-hydroxyethyl)-

Synonyms

EtFOSE

N-ethylperfluorooctanesulfonamidoethanol

Structural Formula

1691992.jpg

Molecular Formula

C12H10F17NO3S

Molecular Weight (g/mol)

571.25

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)N(CCO)CC

CAS RN

24448-09-7

Chemical Name

1-Octanesulfonamide, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N-(2-hydroxyethyl)-N-methyl-

Synonyms

MeFOSE

N-methylperfluorooctanesulfonamidoethanol

Structural Formula

24448097.jpg

Molecular Formula

C11H8F17NO3S

Molecular Weight (g/mol)

557.22

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)N(C)CCO

CAS RN

40630-61-3

Chemical Name

1-Octanesulfonamide, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N,N-bis(2-hydroxyethyl)-

Synonyms

N,N-bis(2-hydroxyethyl)perfluorooctanesulfonamide

Structural Formula

40630613.jpg

Molecular Formula

C12H10F17NO4S

Molecular Weight (g/mol)

587.25

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)N(CCO)CCO

CAS RN

376-14-7

Chemical Name

2-Propenoic acid, 2-methyl-, 2-[ethyl[(heptadecafluorooctyl)sulfonyl]amino]ethyl ester

Synonyms

EtFOSMAC

N-ethylperfluorooctanesulfonamidoethyl methacrylate

Structural Formula

376147.jpg

Molecular Formula

C16H14F17NO4S

Molecular Weight (g/mol)

639.32

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)N(CCOC(=O)C(=C)C)CC

CAS RN

423-82-5

Chemical Name

Acrylic acid, ester with N-ethyl-1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-N-(2-hydroxyethyl)-1-octanesulfonamide

Synonyms

EtFOSAC

N-ethylperfluorooctanesulfonamidoethyl acrylate

Structural Formula

423825.jpg

Molecular Formula

C15H12F17NO4S

Molecular Weight (g/mol)

625.30

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)
C(F)(F)C(F)(F)F)S(=O)(=O)N(CCOC(=O)C=C)CC

Methacrylate and Acrylate Polymers with Perfluorooctanesulfonamide Side Chains

CAS RN

127133-66-8

Chemical Name

2-Propenoic acid, 2-methyl-, polymers with butyl methacrylate, lauryl methacrylate and 2-[methyl[(perfluoro-C4-8-alkyl)sulfonyl]amino]ethyl methacrylate

CAS RN

594864-11-6

Chemical Name

2-Propenoic acid, butyl ester, polymer with 2-[butyl[(heptadecafluorooctyl)sulfonyl]amino]ethyl 2-propenoate and 2-methylpropyl 2-propenoate

CAS RN

68298-62-4

Chemical Name

2-Propenoic acid, 2-[butyl[(heptadecafluorooctyl)sulfonyl]amino]ethyl ester, telomer with 2-[butyl[(pentadecafluoroheptyl)sulfonyl]amino]ethyl 2-propenoate, methyloxirane polymer with oxirane di-2-propenoate, methyloxirane polymer with oxirane mono-2-propenoate and 1-octanethiol

Synonyms

N-butylperfluorooctanesulfonamidoethyl acrylate telomer with N-butylperfluorooctanesulfonamidoethyl acrylate propylene glycol polymer with ethylene glycol-propylene glycol copolymer diacrylate with ethylene glycol-propylene glycol copolymer monoacrylate and n-octyl mercaptan

Structural Formula

68298624.jpg

SMILES

C(C=C)(=O)OCC[N@@](S(C(F)(F)C(C(C(C(C(C(C
F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(=O)=O)CCCC.
C(C=C)(=O)[O-].C(S)CCCCCCC.O1CC1.O1[C@@H]
(C1)C.C(C=C)(=O)[O-].C(C=C)(=O)[O-].O1CC1.O1
[C@@H](C1)C.C(C=C)(=O)OCC[N@@](S(=O)(=O)
C(C(C(C(C(C(C(F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)(F)F)
CCCC

CAS RN

68329-56-6

Chemical Name

2-Propenoic acid, eicosyl ester, polymer with 2-[[(heptadecafluorooctyl)sulfonyl]methylamino]ethyl 2-propenoate, hexadecyl 2-propenoate, 2-[methyl[(nonafluorobutyl)sulfonyl]amino]ethyl 2-propenoate, 2-[methyl[(pentadecafluoroheptyl)sulfonyl]amino]ethyl 2-propenoate, 2-[methyl[(tridecafluorohexyl)sulfonyl]amino]ethyl 2-propenoate, 2-[methyl[(undecafluoropentyl)sulfonyl]amino]ethyl 2-propenoate and octadecyl 2-propenoate

CAS RN

68555-90-8

Chemical Name

2-Propenoic acid, butyl ester, polymer with 2-[[(heptadecafluorooctyl)sulfonyl]methylamino]ethyl 2-propenoate, 2-[methyl[(nonafluorobutyl)sulfonyl]amino]ethyl 2-propenoate, 2-[methyl[(pentadecafluoroheptyl)sulfonyl]amino]ethyl 2-propenoate, 2-[methyl[(tridecafluorohexyl)sulfonyl]amino]ethyl 2-propenoate and 2-[methyl[(undecafluoropentyl)sulfonyl]amino]ethyl2-propenoate

Synonyms

butyl acrylate, polymer with N-methylperfluoroalkyl-C4-8-sulfonamidoethyl acrylates

Structural Formula