Indirect precursors to perfluorocarboxylic acids: Environment tier II assessment

08 March 2019

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CAS Registry Numbers: 865-86-1, 39239-77-5, 68391-08-2, 2144-54-9, 6014-75-1, 4980-53-4, 59778-97-1, 65104-66-7, 85631-54-5, 65605-58-5, 65605-59-6, 65605-60-9, 65636-35-3, 68239-43-0, 150135-57-2, 203743-03-7, 65104-45-2, 115592-83-1, 119973-85-2, 196316-34-4, 125768-41-4, 220237-52-5, 65530-83-8, 65530-69-0, 65530-59-8, 65605-57-4, 65605-56-3, 94095-37-1, 71608-61-2, 68891-05-4, 376364-33-9, 135228-60-3, 144468-32-6, 118102-37-7, 118102-38-8, 332076-28-5, 332076-33-2, 332076-34-3, 68990-40-9, 253873-70-0, 65530-74-7, 65530-63-4, 65530-64-5, 74499-44-8, 65545-80-4, 70983-59-4, 98219-29-5, 115340-82-4, 92129-34-5, 115535-36-9, 127133-57-7, 145477-02-7, 153325-45-2, 65530-57-6, 71002-41-0, 68187-47-3, 68187-25-7, 70983-60-7, 71356-38-2, 68140-21-6, 68516-17-6, 84238-62-0, 70969-47-0, 113089-67-1, 253682-98-3, 253682-97-2, 185630-70-0, 459415-06-6, 524729-93-9, 1094598-90-9, 325966-78-7, 119973-84-1, 220713-37-1, 374928-93-5, 97136-02-2, 101896-32-6, 220713-74-6, 220713-85-9, 374928-92-4, 329201-80-1, 65530-58-7, 254889-79-7, 254889-72-0

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 a group of 83 fluorochemicals. The chemicals in this group include neutral and ionic organic substances of moderate to high molecular weight, and polymers with fluorinated side-chains. All of these substances are structurally related in that they contain a chain of perfluorinated carbons that are linked to another structural unit by at least one non-fluorinated carbon atom. Although some substances in this group are mixtures of discrete chemicals with a range of perfluorinated chain lengths, all potentially have at least one component chemical which has a chain of nine or more perfluorinated carbon atoms.

NICNAS has developed an action plan to assess and manage chemicals which may degrade to perfluorinated carboxylic acids (PFCAs), perfluoroalkyl sulfonates and similar chemicals (NICNAS, 2018). The primary assumption outlined in this action plan is that chemicals with a perfluorinated carbon chain terminated with an alkyl or aryl group will degrade to form a mix of perfluorocarboxylic acids, with both the original perfluorinated chain length and one less perfluorinated carbon atom.

The environmental biodegradation of chemicals in this group is expected to primarily result in release of perfluorocarboxylic acids with one less perfluorinated carbon atom than the parent chemical. On this basis, the chemicals in this group are considered to have the potential to degrade to perfluorononanoic acid and/or a longer chain perfluorocarboxylic acid homologue. These potential long-chain perfluorocarboxylic acid degradants are of concern because the immediate shorter chain homologue, perfluorooctanoic acid (PFOA), has been identified as a persistent, bioaccumulative and toxic (PBT) chemical according to domestic environmental hazard criteria. Chemicals with these hazard characteristics are of high concern to the environment and PFOA (and substances which may degrade to PFOA) are subject to increasingly stringent regulatory controls in other developed countries (NICNAS, 2015a).

Longer chain perfluorocarboxylic acids have received attention internationally for similar reasons. In 2009, long-chain perfluorocarboxylic acids were identified as PBT substances in the United States of America (USA) (US EPA, 2009). Canada has prohibited the introduction of long-chain perfluorocarboxylic acids and their precursors (Government of Canada, 2018b). A series of long-chain perfluorocarboxylic acids has also been identified as Substances of Very High Concern in the European Union due to their very persistent and very bioaccumulative (vPvB) hazard characteristics (ECHA, 2012a, b, c, d).

The degradation of perfluorinated carboxylic acids is very slow compared with their rate of formation from degradation of the precursors and perfluorinated carboxylic acids will be the final degradants from multiple precursors. Therefore, the amount of perfluorinated carboxylic acids 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 release of perfluorinated carboxylic acids to the environment.

Chemical Identity

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, 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, 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 Fluorotelomer Alcohols

CAS RN

865-86-1

Chemical Name

1-Dodecanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,12-heneicosafluoro-

Synonyms

10:2 FTOH

10:2 fluorotelomer alcohol

Structural Formula

865861.jpg

Molecular Formula

C12H5F21O

Molecular Weight

564.13

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCO

CAS RN

39239-77-5

Chemical Name

1-Tetradecanol, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,14-pentacosafluoro-

Synonyms

12:2 FTOH

12:2 fluorotelomer alcohol

Structural Formula

39239775.jpg

Molecular Formula

C14H5F25O

Molecular Weight

664.15

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCO

The substance represented by CAS RN 68391-08-2 is a UVCB. Representative chemical identity information is provided for the two end members of this substance below. This substance is a mixture of fluorotelomer alcohols with chains of six to twelve perfluorinated carbons.

CAS RN

68391-08-2

Chemical Name

Alcohols, C8-14, .gamma.-.omega.-perfluoro

Representative Structural Formula

68391082.jpg

Representative Molecular Formula

C8H5F13O
C14H5F25O

Representative Molecular Weight (g/mol)

364.10
664.15

Representative SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCO

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCO

CAS RN

2144-54-9

Chemical Name

2-Propenoic acid, 2-methyl-, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,12-heneicosafluorododecyl ester

Synonyms

10:2 FTMAC

10:2 fluorotelomer methacrylate

Structural Formula

2144549.jpg

Molecular Formula

C16H9F21O2

Molecular Weight

632.21

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

CAS RN

6014-75-1

Chemical Name

Methacrylic acid, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,14-pentacosafluorotetradecyl ester

Synonyms

12:2 FTMAC

12:2 fluorotelomer methacrylate

Structural Formula

6014751.jpg

Molecular Formula

C18H9F25O2

Molecular Weight

732.22

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

CAS RN

4980-53-4

Chemical Name

Methacrylic acid, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,16,16-nonacosafluorohexadecyl ester

Synonyms

14:2 FTMAC

14:2 fluorotelomer methacrylate

Structural Formula

4980534.jpg

Molecular Formula

C20H9F29O2

Molecular Weight

832.24

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

CAS RN

59778-97-1

Chemical Name

2-Propenoic acid, 2-methyl-, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,16, 17,17,18,18,18-tritriacontafluorooctadecyl ester

Synonyms

16:2 FTMAC

16:2 fluorotelomer methacrylate

Structural Formula

59778971.jpg

Molecular Formula

C22H9F33O2

Molecular Weight

932.25

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

CAS RN

65104-66-7

Chemical Name

2-Propenoic acid, 2-methyl-, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14,15,15,16,16, 17,17,18,18,19,19,20,20,20-heptatriacontafluoroeicosyl ester

Synonyms

18:2 FTMAC

18:2 fluorotelomer methacrylate

Structural Formula

65104667.jpg

Molecular Formula

C24H9F37O2

Molecular Weight

1032.27

SMILES

C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

The substance represented by CAS RN 85631-54-5 is a UVCB. Representative chemical identity information is provided for the two end members of this substance below. This substance is a mixture of fluorotelomer acrylates with chains of six to twelve perfluorinated carbons.

CAS RN

85631-54-5

Chemical Name

2-Propenoic acid, .gamma.-.omega.-perfluoro-C8-14-alkyl esters

Representative Structural Formula

85631545.jpg

Representative Molecular Formula

C11H7F13O2

C17H7F25O2

Representative Molecular Weight (g/mol)

418.15
718.20

Representative SMILES

C=CC(=O)OCCC(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)(F)

C=CC(=O)OCCC(F)(F)C(F)(F)C(F)(F)C(F)(F)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)

Methacrylate and Acrylate Polymers

The substance represented by CAS RN 65605-58-5 is a polymer with side chains terminated with perfluorinated segments of various lengths. Representative chemical identity information is provided for the constituent monomers below.

CAS RN

65605-58-5

Chemical Name

2-Propenoic acid, 2-methyl-, dodecyl ester, polymer with .alpha.-fluoro-.omega.-[2-[(2-methyl-1-oxo-2-propenyl)oxy]ethyl]poly(difluoromethylene)

Synonyms

dodecyl methacrylate, polymer with perfluoroalkylethyl methacrylate

Representative Structural Formula

65605585.jpg

Representative SMILES

CCCCCCCCCCCCOC(=O)C(=C)C.C(F)(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)C(F)(F)CCOC(=O)C(=C)C

The substance represented by CAS RN 65605-59-6 is a polymer with side chains terminated with perfluorinated segments of various lengths. Representative chemical identity information is provided for the constituent monomers below.

CAS RN

65605-59-6

Chemical Name

2-Propenoic acid, 2-methyl-, dodecyl ester, polymer with .alpha.-fluoro-.omega.-[2-[(2-methyl-1-oxo-2-propenyl)oxy]ethyl]poly(difluoromethylene) and N-(hydroxymethyl)-2-propenamide

Synonyms

dodecyl methacrylate, polymer with perfluoroalkylethyl methacrylate and N-hydroxymethylacrylamide

Representative Structural Formula