Indirect precursors of perfluorobutanesulfonate (PFBS): Environment tier II assessment

13 February 2015

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CAS Registry Number: 34454-97-2, 34449-89-3, 34455-00-0, 68957-59-5, 53518-00-6, 67939-95-1, 67584-51-4, 67939-89-3, 17329-79-2, 68298-79-3, 68310-18-9, 68568-54-7, 68900-97-0.

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 12 perfluorobutanesulfonamide derivatives and one perfluorobutanesulfonic ester.

The chemicals in this group are structurally related compounds in that they all contain a chain of four perfluorinated carbons linked to a terminal sulfonamide or sulfonic ester group.

The assessment of this group has been conducted in accordance with the NICNAS Action Plan for Assessment and Management of Chemicals which may degrade to Perfluorinated Carboxylic Acids, Perfluoroalkylsulfonates and similar chemicals (the Action Plan). The primary assumption outlined in the Action Plan is that chemicals with a perfluorinated chain terminated by a sulfonyl group will degrade to the perfluoroalkylsulfonate. On this basis the chemicals in this group are each considered to have the potential to degrade into the environmentally persistent perfluorobutanesulfonate anion (PFBS). More information on the plan can be found in Appendix G of the NICNAS Handbook for Notifiers.

Chemicals based on PFBS were introduced as alternatives to the longer chain perfluoroalkyl sulfonates (PFAS) (containing carbon chain lengths of 6 or higher) including substances which may be a source of the hazardous perfluorooctanesulfonate anion (PFOS) in the environment (UNEP, 2013). Perfluorooctanesulfonic acid and certain PFOS-related substances have recently been identified as Persistent Organic Pollutants under Annex B of the Stockholm Convention on Persistent Organic Pollutants. These substances are also listed on Annex III of the Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade. Further information on PFOS can be found in the Environment Tier II Assessment of the Direct Precursors to Perfluorooctanesulfonate (PFOS) group (see NICNAS, 2015a).

The degradation of PFBS is very slow compared with its rate of formation from degradation of the precursors and PFBS will be the final degradant from multiple precursors. Therefore, the amount of PFBS 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 PFBS to the environment. The IMAP-Environment Tier II assessment of Perfluorobutanesulfonic Acid and its Direct Precursors (see NICNAS, 2015b) has been used as a reference assessment.

Chemical Identity

In this assessment, "PFBS" is used to denote the conjugate base anion of perfluorobutanesulfonic acid (i.e. the perfluorobutanesulfonate 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.

CAS RN

34454-97-2

Chemical Name

1-Butanesulfonamide, 1,1,2,2,3,3,4,4,4-nonafluoro-N-(2-hydroxyethyl)-N-methyl-

Synonyms

N-MeFBSE alcohol

N-Methylperfluorobutanesulfonamidoethyl alcohol

Structural Formula

34454972.jpg

Molecular Formula

C7H8F9NO3S

Molecular Weight (g/mol)

357.19

SMILES

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

CAS RN

34449-89-3

Chemical Name

1-Butanesulfonamide, N-ethyl-1,1,2,2,3,3,4,4,4-nonafluoro-N-(2-hydroxyethyl)-

Synonyms

N-EtFBSE alcohol

N-Ethylperfluorobutanesulfonamidoethyl alcohol

Structural Formula

34449893.jpg

Molecular Formula

C8H10F9NO3S

Molecular Weight (g/mol)

371.22

SMILES

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

CAS RN

34455-00-0

Chemical Name

1-Butanesulfonamide, 1,1,2,2,3,3,4,4,4-nonafluoro-N,N-bis(2-hydroxyethyl)-

Synonyms

N-EtFBSE diol

N,N-Bis(hydroxyethyl)perfluorobutanesulfonamide

Structural Formula

34455000.jpg

Molecular Formula

C8H10F9NO4S

Molecular Weight (g/mol)

387.22

SMILES

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

CAS RN

68957-59-5

Chemical Name

1-Butanesulfonamide, N-[3-(dimethylamino)propyl]-1,1,2,2,3,3,4,4,4-nonafluoro-, monohydrochloride

Synonyms

N-(3-(dimethyl)aminopropyl)perfluorobutanesulfonamide monohydrochloride

Structural Formula

68957595.jpg

Molecular Formula

C9H14ClF9N2O2S

Molecular Weight (g/mol)

420.72

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)F)S(=O)(=O)NCCCN(C)C.Cl

CAS RN

53518-00-6

Chemical Name

1-Propanaminium, N,N,N-trimethyl-3-[[(nonafluorobutyl)sulfonyl]amino]-, chloride

Synonyms

N-(3-(trimethyl)aminopropyl)perfluorobutanesulfonamide chloride

Structural Formula

53518006.jpg

Molecular Formula

C10H16ClF9N2O2S

Molecular Weight (g/mol)

434.75

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)F)S(=O)(=O)NCCC[N+](C)(C)C.[Cl-]

CAS RN

67939-95-1

Chemical Name

1-Propanaminium, N,N,N-trimethyl-3-[[(nonafluorobutyl)sulfonyl]amino]-, iodide

Synonyms

N-(3-(trimethyl)aminopropyl)perfluorobutanesulfonamide iodide

Structural Formula

67939951.jpg

Molecular Formula

C10H16F9IN2O2S

Molecular Weight (g/mol)

526.20

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)F)S(=O)(=O)NCCC[N+](C)(C)C.[I-]

CAS RN

67584-51-4

Chemical Name

Glycine, N-ethyl-N-[(nonafluorobutyl)sulfonyl]-, potassium salt

Synonyms

potassium N-EtFBSA acetate

potassium N-ethylperfluorobutanesulfonamide acetate

Structural Formula

67584514.jpg

Molecular Formula

C8H7F9KNO4S

Molecular Weight (g/mol)

423.29

SMILES

C(F)(F)(C(F)(F)C(F)(F)C(F)(F)F)S(=O)(=O)N(CC(=O)[O-])CC.[K+]

CAS RN

67939-89-3

Chemical Name

Ethanol, 2-[ethyl[(1,1,2,2,3,3,4,4,4-nonafluorobutyl)sulfonyl]amino]-, dihydrogen phosphate (ester)

Synonyms

N-EtFBSE phosphate

N-Ethylperfluorobutanesulfonamidoethyl phosphate

Structural Formula

67939893.jpg

Molecular Formula

C8H11F9NO6PS

Molecular Weight (g/mol)

451.20

SMILES

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

CAS RN

17329-79-2

Chemical Name

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

Synonyms

N-EtFBSE acrylate

N-Ethylperfluorobutanesulfonamidoethyl acrylate

Structural Formula

17329792.jpg

Molecular Formula

C11H12F9NO4S

Molecular Weight (g/mol)

425.27

SMILES

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

The substance represented by CAS RN 68298-79-3 is a mixture of discrete organic chemicals. Representative chemical structure information is provided below. However, it should be noted that this substance is expected to include chemicals with polyethylene glycol chains of varying lengths.

CAS RN

68298-79-3

Chemical Name

Poly(oxy-1,2-ethanediyl), .alpha.-[2-[ethyl[(nonafluorobutyl)sulfonyl]amino]ethyl]-.omega.-hydroxy-

Synonyms

PEG N-EtFBSE

Polyethylene glycol N-ethylperfluorobutanesulfonamide

Representative Structural Formula

68298793.jpg

Representative Molecular Formula

C16H26F9NO7S

Representative Molecular Weight (g/mol)

547.43

Representative SMILES

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

The substance represented by CAS RN 68310-18-9 is a mixture of discrete organic chemicals. Representative chemical structure information is provided below. However, it should be noted that this substance is expected to include chemicals with polypropylene glycol chains of varying lengths.

CAS RN

68310-18-9

Chemical Name

Poly[oxy(methyl-1,2-ethanediyl)], .alpha.-[2-[ethyl[(nonafluorobutyl)sulfonyl]amino]ethyl]-.omega.-hydroxy-

Synonyms

PPG N-EtFBSE

Polypropylene glycol N-ethylperfluorobutanesulfonamide

Representative Structural Formula