Indirect precursors to perfluoroalkyl sulfonates: Environment tier II assessment

03 July 2015

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CAS Registry Number: 68555-74-8, 68555-72-6, 68298-06-6, 68555-75-9, 34455-03-3, 1893-52-3, 68555-76-0, 68555-73-7, 59071-10-2, 68957-60-8, 68957-55-1, 68957-57-3, 68957-61-9, 52166-82-2, 68957-58-4, 73772-32-4, 81190-38-7, 38850-58-7, 67940-02-7, 68555-81-7, 67584-58-1, 67584-52-5, 67584-53-6, 67584-62-7, 67939-90-6, 67969-65-7, 67923-61-9, 67939-98-4, 67939-97-3, 67939-94-0, 68298-80-6, 68310-17-8, 56372-23-7, 68259-38-1, 68298-81-7, 68958-60-1, 68259-39-2, 68541-02-6, 68891-99-6, 68815-72-5, 68891-98-5, 68541-01-5, 68891-97-4

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 the new 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 43 chemicals. The chemicals in this group are structurally related compounds in that they all contain a chain of either five, six or seven 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, which can be found in Appendix G of the Handbook for Notifiers on the NICNAS website (NICNAS, 2015d). 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 (of the same chain length). On this basis the chemicals in this group are expected to degrade to form the C5 perfluoropentanesulfonate anion (PFPeS), the C6 perfluorohexanesulfonate anion (PFHxS), or the C7 perfluoroheptanesulfonate anion (PFHpS) in the aquatic environment.

The perfluorinated anions that can be released by the chemicals in this group have chain lengths which are intermediate to the homologous C4 perfluorobutanesulfonate anion (PFBS) and the C8 perfluorooctanesulfonate anion (PFOS). Data currently available for simple salts of PFBS indicate that although this short-chain anion is exceptionally persistent in the environment, it is not bioaccumulative or toxic (NICNAS, 2015e). However, the long-chain PFOS anion is persistent, bioaccumulative, and toxic, and substances which release this anion are considered to pose a significant hazard both to human health and the environment (NICNAS, 2015a).

Degradation of the C5 to C7 perfluoroalkyl sulfonate anions is very slow compared with their rate of formation from the degradation of their precursors. Therefore, the concentration of C5 to C7 perfluoroalkyl sulfonate anions in the environment is expected to be higher than that of any of their respective 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 the C5 to C7 perfluoroalkyl sulfonate anions to the environment. The IMAP Environment Tier II assessment for Direct Precursors to Perfluoroheptanesulfonate (PFHpS), Perfluorohexanesulfonate (PFHxS) and Perfluoropentanesulfonate (PFPeS) has been used as a reference assessment (NICNAS, 2015b).

Chemical Identity

In this assessment, “PFHpS” is used to denote the conjugate base anion of perfluoroheptanesulfonic acid (i.e. the perfluoroheptanesulfonate anion), “PFHxS” is used to denote the conjugate base anion of perfluorohexanesulfonic acid (i.e. the perfluorohexanesulfonate anion), and “PFPeS” is used to denote the conjugate base anion of perfluoropentanesulfonic acid (i.e. the perfluoropentanesulfonate anion) (Buck, et al., 2011).

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. For purposes of presentation the chemicals in this assessment have been sub-grouped below based on similar structural properties and their perfluorinated chain length.

Neutral Organic Derivatives of Perfluoropentanesulfonamides

CAS RN

68555-74-8

Chemical Name

1-Pentanesulfonamide, 1,1,2,2,3,3,4,4,5,5,5-undecafluoro-N-(2-hydroxyethyl)-N-methyl-

Synonyms

MeFPeSE

N-methylperfluoropentanesulfonamidoethanol

Structural Formula

68555748.jpg

Molecular Formula

C8H8F11NO3S

Molecular Weight (g/mol)

407.20

SMILES

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

CAS RN

68555-72-6

Chemical Name

1-Pentanesulfonamide, N-ethyl-1,1,2,2,3,3,4,4,5,5,5-undecafluoro-N-(2-hydroxyethyl)-

Synonyms

EtFPeSE

N-ethylperfluoropentanesulfonamidoethanol

Structural Formula

68555726.jpg

Molecular Formula

C9H10F11NO3S

Molecular Weight (g/mol)

421.23

SMILES

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

CAS RN

68298-06-6

Chemical Name

2-Propenoic acid, 2-[ethyl[(1,1,2,2,3,3,4,4,5,5,5-undecafluoropentyl)sulfonyl]amino]ethyl ester

Synonyms

EtFPeSAC

N-ethylperfluoropentanesulfonamindoethyl acrylate

Structural Formula

68298066.jpg

Molecular Formula

C12H12F11NO4S

Molecular Weight (g/mol)

475.28

SMILES

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

Neutral Organic Derivatives of Perfluorohexanesulfonamides

CAS RN

68555-75-9

Chemical Name

1-Hexanesulfonamide, 1,1,2,2,3,3,4,4,5,5,6,6,6-tridecafluoro-N-(2-hydroxyethyl)-N-methyl-

Synonyms

MeFHxSE

N-methylperfluorohexanesulfonamidoethanol

Structural Formula

68555759.jpg

Molecular Formula

C9H8F13NO3S

Molecular Weight (g/mol)

457.21

SMILES

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

34455-03-3

Chemical Name

1-Hexanesulfonamide, N-ethyl-1,1,2,2,3,3,4,4,5,5,6,6,6-tridecafluoro-N-(2-hydroxyethyl)-

Synonyms

EtFHxSE

N-ethylperfluorohexanesulfonamidoethanol

Structural Formula

34455033.jpg

Molecular Formula

C10H10F13NO3S

Molecular Weight (g/mol)

471.24

SMILES

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

1893-52-3

Chemical Name

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

Synonyms

EtFHxSAC

N-ethylperfluorohexanesulfonamindoethyl acrylate

Structural Formula

1893523.jpg

Molecular Formula

C13H12F13NO4S

Molecular Weight (g/mol)

525.28

SMILES

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

Neutral Organic Derivatives of Perfluoroheptanesulfonamides

CAS RN

68555-76-0

Chemical Name

1-Heptanesulfonamide, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoro-N-(2-hydroxyethyl)-N-methyl-

Synonyms

MeFHpSE

N-methylperfluoroheptanesulfonamidoethanol

Structural Formula

68555760.jpg

Molecular Formula

C10H8F15NO3S

Molecular Weight (g/mol)

507.22

SMILES

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

68555-73-7

Chemical Name

1-Heptanesulfonamide, N-ethyl-1,1,2,2,3,3,4,4,5,5,6,6,7,7,7-pentadecafluoro-N-(2-hydroxyethyl)-

Synonyms

EtFHpSE

N-ethylperfluoroheptanesulfonamidoethanol

Structural Formula

68555737.jpg

Molecular Formula

C11H10F15NO3S

Molecular Weight (g/mol)

521.24

SMILES

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

59071-10-2

Chemical Name

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

Synonyms

EtFHpSAC

N-ethylperfluoroheptanesulfonamindoethyl acrylate

Structural Formula

59071102.jpg

Molecular Formula

C14H12F15NO4S

Molecular Weight (g/mol)

575.29

SMILES

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

Alkyl Ammonium and Amine Derivatives of Perfluoropentanesulfonamides

CAS RN

68957-60-8

Chemical Name

1-Pentanesulfonamide, N-[3-(dimethylamino)propyl]-1,1,2,2,3,3,4,4,5,5,5-undecafluoro-, monohydrochloride

Synonyms

N-(3-(dimethylaminopropyl)perfluoropentanesulfonamide monohydrochloride

Structural Formula

68957608.jpg

Molecular Formula

C10H14ClF11N2O2S

Molecular Weight (g/mol)

470.73

SMILES

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

CAS RN

68957-55-1

Chemical Name

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

Synonyms

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

Structural Formula